1996 Zx 25 With A Pad Bottom

[SilverBack]

Please spread some of your wisdom!!!

These are some pictures of a 1996 25 ZX with a PAD BOTTOM. It has a 502 MAG and a Bravo 1. How many of you have seen one or own one? How did they perform? This boat has 9 inches between the prop shaft and the bottom of the hull. What do you experts think? Shouldn't this be a good bit higher? Has anyone put more power to a 25 ZX? Has anyone raised the X or put a shorty on one? How did it act? What about an extension box? Give me some input. Any input is very much appreciated!!

Thanks for the help!

Buzilla, Is this the boat that you were talking about in southern Florida?

[BlownCrewCab]

Splain to me what a mans got to do to have a girl like in the last pic?????

The pics sure look like a VERY LOW Drive, and I Think theres allot of performance Left in that set up. just raising the X will do wonders (for speed)
Does anyone else have one of these padded Donzi's???
whats your X Dim Look like?????

[BUIZILLA]

that's the one...

[Last Real Texan]

Splain to me what a mans got to do to have a girl like in the last pic?????

??
Get a 25 ZX and she is all yours

[joel3078]

Guess which one has higher maintenance costs! :smash:

[SilverBack]

Last Texan....is that a guarantee?????

[Last Real Texan]

Last Texan....is that a guarantee?????
only if it runs over 80:lightning

[SilverBack]

So I guess getting back to the question at hand, what will it take to make this boat run 80?

[BUIZILLA]

$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

[SilverBack]

Do you think that it would still be ok for just cruising if you did the following 4 mods?

1. M-3 Procharger
2. -2 shorty
3. Raise the X 3 inches (this would put the prop shaft 4 inches below the bottom of the hull) (would you use a stand off box???)
4. A large diameter 5 or 6 blade prop.

What will be the potential cons to doing this?????

[SilverBack]

What about a 12" extension box? Would that help drivability?

[mjw930]

I think a 12" box with a 3" rise would be a great addition and not effect driveability at all, so long as you got it propped right.

I think this package raises as well as moves it back and the integrated steering completes the package.

http://www.everettperformance.com/images/productpics/14LG.gif

http://www.everettperformance.com/products.asp?category=Zeiger%20Marine&subcategory=Steering%20Products&id=14

[The Hedgehog]

Better drop the Q & Q if you go for the ext box. I think that they look cool and like them. You will go where no man has gone before. 80mph takes some hp no matter how you slice it. Dialed in right - mid 70's. Dialed in right with 620hp and you might see 80.

You want to play in the 90's you will need big hp and dialed in. Tex is dialed in with a twin step and high 600-low 700 hp with shorty. He gets 85 on a good day.

I still want to know if a 26 ZX likes one. So far I think I night have enough hp to be scary.

[mjw930]

Better drop the Q & Q if you go for the ext box. I think that they look cool and like them. You will go where no man has gone before. 80mph takes some hp no matter how you slice it. Dialed in right - mid 70's. Dialed in right with 620hp and you might see 80.

You want to play in the 90's you will need big hp and dialed in. Tex is dialed in with a twin step and high 600-low 700 hp with shorty. He gets 85 on a good day.

I still want to know if a 26 ZX likes one. So far I think I night have enough hp to be scary.

Wow, I never realized just how much faster the Velocity hulls are than the more "traditional" designs. I had a 26 Velocity (280 by today's nomenclature) with a 540 hp 461 that was a solid 84 mph with full tank and passengers. Nothing special in the outdrive department, just a Bravo with a labbed 26" Bravo 1 prop spinning @ 5800 rpm. My X was high but all Velocity's run a high X.

I know it's sacrilege on a Donzi board to say this but at what point do you decide your money is better spent on a faster hull than insane power........

[The Hedgehog]

I actually looked at them as an option. They were a decent looking boat. Not near the ride quality as the ZX though. I ran along in the low 70's with one at Center Hill Lake in little 2 footers. I could see daylight under his hull a good bit. They were taking a beating.

FastTrucker's big zx runs mid 70's. He spanks Velocities on a regular basis during rough days on the Bay.

[mjw930]

A lot is going to depend on the setup, driver and specific Velocity. For example, the 260 (24') is simply a cut down 280 and it rides like one. The older 320 is also a piece of crap with way too much lift dialed into the bottom and a CG that's all out of whack unless you run a high HP single.

One thing many Velocity owners do is run too much trim in the rougher stuff. It's especially prevalent with the owners that have low HP boats but want to keep up with the big boys.

Case in point, when my 26 has a 350 HP 454 Mag in it running @ 70 mph was possible but you had to trim it way out and get it up on the rear pad. Anything over 2' was not comfortable unless I dropped back down to ~60 with the trim in. Fast forward 1 season with the rebuilt 540 HP motor and things were completely different. The trick to running a Velocity (or any pad bottomed boat) in the rough stuff is keeping the bow down enough to allow the deadrise in front of the pad to slice into the next wave. With the higher power I could run 70 mph ALL DAY LONG in 3' - 5' seas and not take a beating. Sure, I'd be seeing a lot of air (My wide used to joke I needed a pilots license to "fly" the boat) but being able to keep a level attitude and using the HP to push off the wave into the next one instead of bouncing from wave to wave made for a really fun, fast ride.

Each boat is different and requires seat time and an understanding of it's handling quirks. Pad bottomed boats with notched transom's are insanely fast in the right conditions but they are all "drivers" boats that require someone to understand their strengths an weaknesses for a good time to be had.

Sorry for the novel but I have to uphold the mantle when someone makes a statement about "spanking" every one on the bay. I "spanked" quite a few "deep-V" offshore boats with my Velocity and rarely had a bad day on the water. I WILL confess that there were times when I wished I didn't have a pad bottomed boat when the seas really got snotty but I liked going 80+ mph with the "midget" motor ;)

[SilverBack]

MJW930,
What do you mean exactly when you say NOTCHED transom? Do you have a picture of the pad on your boat? Are you saying that you could do 80 with 540 hp? How far was your prop shaft from the bottom of your hull? Did you raise your X or add a short lower when you added the power?

[mjw930]

What do you mean exactly when you say NOTCHED transom? Do you have a picture of the pad on your boat? Are you saying that you could do 80 with 540 hp? How far was your prop shaft from the bottom of your hull? Did you raise your X or add a short lower when you added the power?

The notched transom means the pad or keel ends ~8" - 12" from the true transom, creating the same effect as a standoff box. The notch allows the X-Dimension to be higher than a "normal" transom. As the water exits the transom on all boats it starts to move up (picture the angle of the water coming off the transom at speed being less then 90 degrees). On a notched transom the water exits the pad and starts it upward motion 8" - 12" earlier than a normal boat. That allows you to raise the X and still keep a good bite on the water.

The picture below is of the rear of my Velocity. The notch is the area from there the pad ends and the boat ends. The X-dimension is as it came from the factory, it's about 4" - 6" higher than what would be considered "normal" in a straight V hull.

[Last Real Texan]

I will give this a stab.......
If you want to see 80 GPS it is going to be very difficult, to say the least.
Strip down the cabin, take out all excessive weight and run it on fumes.
You can make it fast though
Realisticly you can expect 600-615 PSHP at best from the 502 mag with an M-3 pushing 5 lbs of boost.
if and if you leave the drive height alone you will be able to run a 3 Blade mirage plus and you may be able to spin it to 5400....that is pushing the upper limit on the Mag valve train for anything other than short bursts.
Spin it to 5400 and with 14 percent slip you should see 79.2 mph with good water and the right air temps and the moon and stars aligned perfectly....
you are raising some good questions and it will be a great project for sure, but do it with dillagence and take your time to set it up properly and you will have a lot of fun with it, do it wrong and you will be scratching your head saying why did it cost so much and gain so little.
If it was me I would do the power upgrade first before monkeying with the drive height and boxes and see what it gets you and then go from there. Some boats like boxes and some dont. The fact your boat is shorter it may carry the bow with a shorter drive height and it may not, best to borrow a shorty and go from there. Bill and I tried a shorty on his non step 27 ZX and it could not carry the bow and had a ton of slip .....no worky...
Drop me a line if you want to talk 478-737-0003
Bryan

[mjw930]

MJW930,
What do you mean exactly when you say NOTCHED transom? Do you have a picture of the pad on your boat? Are you saying that you could do 80 with 540 hp? How far was your prop shaft from the bottom of your hull? Did you raise your X or add a short lower when you added the power?

BTW, that boat ran 68 mph on GPS with 350 HP with a normal cruising load of fuel and passengers spinning a 24" hydromotive @ 4800 RPM. With ~560 HP @ 5800 RPM (it made 625 @ 6500 RPM on a pass with better headers but we never propped it for that RPM since the torque started to fall after 6000) it ran 84 mph on GPS with a normal load, 85.7 on GPS on fumes trimmed way out in 1' - 2' chop (needed the chop to get air under the hull). That's with a labbed 26" Bravo 1 and ~10% slip.

The boat was a true 26' 3" bow to stern and weighed in at around 5200 lbs dry and the bottom was blueprinted.

See the dyno chart below.

[mjw930]

Some boats like boxes and some dont. The fact your boat is shorter it may carry the bow with a shorter drive height and it may not, best to borrow a shorty and go from there. Bill and I tried a shorty on his non step 27 ZX and it could not carry the bow and had a ton of slip .....no worky...

Bryan

It's not surprising the shorty alone didn't work, you need to move the drive back AND raise it to reduce drag and increase leverage.

[SilverBack]

Thanks guys!! MJW930, That pad on your boat sure does look a lot wider than the one on mine and I see what you are talking about on the notched hull. How far forward does the pad run on your hull?

LRT, Thanks for the info. I know from talking to Bill that you guy have done a lot with the ZX hulls. Does either of your step hulls have pads? I was talking to Blown Crew Cab and he says that this pad that I have will be like rideing up on a ski. What would be a good time of day to call?

The only reson I was thinking about raising the x and doing the box was trying to kill two birds with one stone thing. If I take the engine out to do heads why not go ahead and do the glass work?

Thanks guys for all of the good information!!!

[mjw930]

From memory I think the pad extended forward at least 12 feet. Also note the full length lifting strakes and the reverse chine. All of that adds to the lift, you don't need much prop lift to carry the bow on these designs. It also added up to a boat that could pull almost .8G in a turn without slipping.

Overall the boat was a lot of fun but honestly, I'm willing to forgo the ultimate speed for a more comfortable ride. If I get into another boat like that I'm more inclined to go with a traditional bottom like the Active Thunder or Pantera in the smaller boats or a ventilated design if I get into the 35'+ boats.

Actually, the boat I would love to have sitting next to the 22 Classic would be a Formula 370 SS with a fast blender :boat:

[Last Real Texan]

Thanks guys!! MJW930, That pad on your boat sure does look a lot wider than the one on mine and I see what you are talking about on the notched hull. How far forward does the pad run on your hull?

LRT, Thanks for the info. I know from talking to Bill that you guy have done a lot with the ZX hulls. Does either of your step hulls have pads? I was talking to Blown Crew Cab and he says that this pad that I have will be like rideing up on a ski. What would be a good time of day to call?

The only reson I was thinking about raising the x and doing the box was trying to kill two birds with one stone thing. If I take the engine out to do heads why not go ahead and do the glass work?

Thanks guys for all of the good information!!!

I am on the road today between 12-2 givwe me a buz

[The Hedgehog]

A lot is going to depend on the setup, driver and specific Velocity. For example, the 260 (24') is simply a cut down 280 and it rides like one. The older 320 is also a piece of crap with way too much lift dialed into the bottom and a CG that's all out of whack unless you run a high HP single.

One thing many Velocity owners do is run too much trim in the rougher stuff. It's especially prevalent with the owners that have low HP boats but want to keep up with the big boys.

Case in point, when my 26 has a 350 HP 454 Mag in it running @ 70 mph was possible but you had to trim it way out and get it up on the rear pad. Anything over 2' was not comfortable unless I dropped back down to ~60 with the trim in. Fast forward 1 season with the rebuilt 540 HP motor and things were completely different. The trick to running a Velocity (or any pad bottomed boat) in the rough stuff is keeping the bow down enough to allow the deadrise in front of the pad to slice into the next wave. With the higher power I could run 70 mph ALL DAY LONG in 3' - 5' seas and not take a beating. Sure, I'd be seeing a lot of air (My wide used to joke I needed a pilots license to "fly" the boat) but being able to keep a level attitude and using the HP to push off the wave into the next one instead of bouncing from wave to wave made for a really fun, fast ride.

Each boat is different and requires seat time and an understanding of it's handling quirks. Pad bottomed boats with notched transom's are insanely fast in the right conditions but they are all "drivers" boats that require someone to understand their strengths an weaknesses for a good time to be had.

Sorry for the novel but I have to uphold the mantle when someone makes a statement about "spanking" every one on the bay. I "spanked" quite a few "deep-V" offshore boats with my Velocity and rarely had a bad day on the water. I WILL confess that there were times when I wished I didn't have a pad bottomed boat when the seas really got snotty but I liked going 80+ mph with the "midget" motor ;)

I did hear that you had to learn how to drive them. I heard folks that owned them and figured them out do like them.

Most fast boats have some type of handling quirks whether it be a step hull or pad V

[BlownCrewCab]

You can see in the pic of the Velocity that their pad is added to the bottom of the boat, and it has the 2 outer edges of the pad to help it track straight. the difference with yours is they just Basicly cut the bottom "V" off your boat and added a flat by blocking the mold so you don't have the the two edges to help with tracking. The Aluminum Cougar 46' had the same thing as yours, sometimes when going through wakes at speed at an angle the boat would follow the wakes, Literally turn to run parrallel with the wakes. I Remember Smitty and Chris Hodges Hit the wall Right by Cigarette Because of it. They where hualin down the canal and went through the wakes of a boat coming the opposite direction and their boat turned right into the wall. I Think you'll need enough gearcase and skeg in the water help steering so going full surface drive would be risky in the handling dept, Just raising your X 3 or 4 inches would be okay (seeing how deep it is now) That handling quirk could be why Donzi went that low to begin with. Only time, trial and error will tell. Not trying to scare you into not doing it, Just letting you know what Could be. If you don't go ballistic over on coming wakes it may never be a problem.

[The Hedgehog]

It's not surprising the shorty alone didn't work, you need to move the drive back AND raise it to reduce drag and increase leverage.

I am pretty sure that something was to be obtained with a combo of shorty, extension box and the right spacer. We were just doing a simple test to satisfy curiosity. I was not ready to throw out the coin to see if it would work. Some straight V-s don't like extension boxes. That is a bunch of work to possibly pick up a few more mph. The boat really drove well the way it was so I backed off.

An extra few mph was always available by throwing on that pulley that is 1/4 inch smaller.

[mjw930]

You can see in the pic of the Velocity that their pad is added to the bottom of the boat, and it has the 2 outer edges of the pad to help it track straight. the difference with yours is they just Basicly cut the bottom "V" off your boat and added a flat by blocking the mold so you don't have the the two edges to help with tracking. The Aluminum Cougar 46' had the same thing as yours, sometimes when going through wakes at speed at an angle the boat would follow the wakes, Literally turn to run parrallel with the wakes. I Remember Smitty and Chris Hodges Hit the wall Right by Cigarette Because of it. They where hualin down the canal and went through the wakes of a boat coming the opposite direction and their boat turned right into the wall. I Think you'll need enough gearcase and skeg in the water help steering so going full surface drive would be risky in the handling dept, Just raising your X 3 or 4 inches would be okay (seeing how deep it is now) That handling quirk could be why Donzi went that low to begin with. Only time, trial and error will tell. Not trying to scare you into not doing it, Just letting you know what Could be. If you don't go ballistic over on coming wakes it may never be a problem.

VERY GOOD ADVICE, you really never know what a boat is going to do when you go beyond the design criteria, especially on a bottom that was "transitional". Not to piss anyone off but if it had really worked well they would have stuck with it.

I really think you should re-evaluate your goals. There are a lot of people who don't need 80+ mph that might give you good money for your boat and give you the funds needed to step into a hull that has some history at the speeds you desire.

[The Hedgehog]

VERY GOOD ADVICE, you really never know what a boat is going to do when you go beyond the design criteria, especially on a bottom that was "transitional". Not to piss anyone off but if it had really worked well they would have stuck with it.

I really think you should re-evaluate your goals. There are a lot of people who don't need 80+ mph that might give you good money for your boat and give you the funds needed to step into a hull that has some history at the speeds you desire.

Actually they did stick with it and add steps in 1997 (on the 27 they dropped the 25). This keel pad was also used on the 26ZX. I have one. A notch was added later. The stepped 27ZX was supposed to have weird handling characteristics in the high 70's. It does. Chine walk and some bounce. Folks said it will be handfull past 75. It levels out after that. Tex took it there and beyond. It is smooth as glass at 80-85! I have driven his boat over 80. It is nice.

Like Tex said. Do it in steps and be methodical. Start with the engine and see how it responds. If it does not like it then you have a built 502. You have lots of options with that. If it does, then do steering. Then the lower. If all that is going well you can add boost. And so on.

These guys are right. If you go out stick on a shorty, ext box and a bunch of power at once, things might get interesting.

[SilverBack]

So you guys are saying that it is not practical to do all the modifications at once. Since I am hard headed let me ask a few more questions. There are a few things that I have never heard anyone say that made their boat handle worse or less reliable.

Have you ever heard of anyone that had trouble with an extension box, dual ram hydraulic steering or an IMCO shorty? What about a procharger and IMCO manifolds. I don't want any chine walk, porposing or blowing out the prop when you accelerate. I just don't want to make the same mistakes that you guys already have. Which of these mods would be more practical? Which have you seen to be more problematic?

Thanks!

[BlownCrewCab]

I Don't see any problem with raising your X dim and adding more power, Like you said before you can run a 5 or 6 blade prop if cavitation is a problem. If it likes those mods, then you can try a box later. that way you'll get an Idea of what each mod does, instead of doing it all at once and not knowing what did what. and you'll only have to take one step back if somthing doesn't work out.

[SilverBack]

I have the procharger, AFR heads and manifolds. I know that I am going to have to get a beefed up drive so the -2 lower seems a natural. Right now my drive is so low that adding the shorty will only raise me to 7 inches below the transom. It seems that raising the X beyond that would be where some think that I am getting iffy. It looks like most modern pad hulls like a little distance between the back of the pad and the prop. If you do the stand off box the external steering is a must.

MJW930, you didn't hurt my feelings with the comment and you may be right. However, I just had my last boat destroyed by a tree and when I started to look for a new boat I never even looked at anything that was not a Donzi. I am on my 3rd and I don't even think they should make anything else!! I don't want to piss anyone off either but it seems like there are a lot of guys out there (and some on this site) that can't or don't want to see past their comfort zone. It seems that some of them think that if it is not a classic Donzi that it is not worth talking about. It also seems that some think the ZX boats shouldn't run past 70. Big Green ZX and Last
Real Texan have proven that these boats can go far beyond that. They both run prochargers and some think that this will instantly blow you engine, put out an eye and the sky will fall as soon as you bolt one on your engine. There are some that just don't care for the Z boats I guess. That is all fine. I really appreciate the fact that you jumped into this thread and shared your experience. I know you have helped me out with some stuff. Thanks and keep it up. I wish there were more people that have played with the X on there boats and extension boxes and prochargers that would jump in and give their insight.

I guess in the mean time while I try to figure this out I will be doing the new paint and interior thing. Maybe that will give some of the others time to chime in!

[chappy]

I have the procharger, AFR heads and manifolds. I know that I am going to have to get a beefed up drive so the -2 lower seems a natural. Right now my drive is so low that adding the shorty will only raise me to 7 inches below the transom. It seems that raising the X beyond that would be where some think that I am getting iffy. It looks like most modern pad hulls like a little distance between the back of the pad and the prop. If you do the stand off box the external steering is a must.
MJW930, you didn't hurt my feelings with the comment and you may be right. However, I just had my last boat destroyed by a tree and when I started to look for a new boat I never even looked at anything that was not a Donzi. I am on my 3rd and I don't even think they should make anything else!! I don't want to piss anyone off either but it seems like there are a lot of guys out there (and some on this site) that can't or don't want to see past their comfort zone. It seems that some of them think that if it is not a classic Donzi that it is not worth talking about. It also seems that some think the ZX boats shouldn't run past 70. Big Green ZX and Last
Real Texan have proven that these boats can go far beyond that. They both run prochargers and some think that this will instantly blow you engine, put out an eye and the sky will fall as soon as you bolt one on your engine. There are some that just don't care for the Z boats I guess. That is all fine. I really appreciate the fact that you jumped into this thread and shared your experience. I know you have helped me out with some stuff. Thanks and keep it up. I wish there were more people that have played with the X on there boats and extension boxes and prochargers that would jump in and give their insight.
I guess in the mean time while I try to figure this out I will be doing the new paint and interior thing. Maybe that will give some of the others time to chime in!
I wish I knew more about the z series so I could jump in and offer advice. Unfortunately I don't. This is a good thread filled with good knowledge, no need to drag it down by throwing stones at members for alleged lack of participation. They could be like me, a classic owner who wants to learn more but is reluctant to offer advice about something he knows nothing about. Just my .02.:bighug:

[BlownCrewCab]

I was brought up to see PAST the comfort zone. Everything I have is Hopped up, beefed up, Tuned up. I Agree with getting all you can get out of somthing. You can easily try the 2" shorter drive and see what you get, If it feels good then do the X for more, worst case you'll have to spacer down a little. No Big Deal....

[The Hedgehog]

I was brought up to see PAST the comfort zone. Everything I have is Hopped up, beefed up, Tuned up. I Agree with getting all you can get out of somthing. You can easily try the 2" shorter drive and see what you get, If it feels good then do the X for more, worst case you'll have to spacer down a little. No Big Deal....

That's good advice.

There is a guy in a Baja that tried an extension box with bad results. He was slinging 900hp or so and did his mods in stages. He did his homework and took some chances. His efforts failed. He spent some serious time playing with the X and different props. It induced some weird handling and a speed loss. He ended up taking it off and selling it.

My engine builder Eddie put one on a Stingray for a guy along with big power. The guy happened to have one around so they did it as almost an experiment. It actually worked pretty well in that case. I pondered doing one in my 26 but think that I have enough going on. I floated it past Eddie. He has rigged a bunch of them. He has done Arnesons and Pulse drives as well. It is somewhat a chance and the boat will go pretty good as it.

[BigGrizzly]

Let me jump in here. I have a procharger on my Criterion, My son has a wipple on his 22ZX neither of us have shortys or extension boxes. Will either or both help -YES- with some fine tuning. Very few mods can just be bolted on without tweaking. Personally I am not putting a shorty on my boat because of cost and work involved on my boat. I can easily gain another 10 MPH on my application, but as of now I am plenty fast and durable. Some say "your never fast enough" well it depends on your check book and your patients. If you like your comfort zone where it is that is fine. As for classics vs Z boats it is just preference. Me I like classics, but my son's ZX is really nice and a head turner where ever he goes. You can't hate his cabin. Remember a boat is a personal thing both in performance and looks. If this were not true there would be one car, one boat, one house style and one color for every thing. So have fun life is short.

[SilverBack]

Chappy and Grizz,
I am not talking about anyone in particular when I made the previous statements! I defiantly was not referring to either of you guys. I love this forum and feel like I have gotten to know many of the characters on here. It just seems that some of the guys are hesitant to jump into a Z thread. I am not saying that they are wrong for that. We are all on here to learn and share and have fun at our hobby that we love. I just think that there is a whole bunch of expertise out there and it may be like Chappy says, that they don't feel like they have direct information about the Z boat but I can tell you that I would love to hear those very peoples opinions and experiences. I would have loved to have bought a 22 classic if it had a cabin that my kids or mom could get out of the sun when we are out on the water all day. I don't need a boat that can handle big water. I never see over a 1 foot chop. I just need the cabin. I am not even all that worried about top end speed right now. I just love the sound of a blower. I would love to be able to cruise at around 60.

Anyway, Whether you post in a Z thread or not I still learn a lot from you guys because I read most of the post that are posted on the website.

Thanks for all of the information that you freely give to us!!

[SilverBack]

These are the pictures of the boat when I got it.


The trailer was rusted out very bad and it was sold with my Ragazza today along with the Bravo drive.

[SilverBack]

Here a a few more pictures of it right before I brought it back from Florida.

[SilverBack]

Here are a few pictures after a couple days in the body shop. I took it straight to my cousins body shop when we got back to Mississippi.

[SilverBack]

We were still getting some of the tape off but we brought it back outside and I took these pics. Still waiting on my new rub rail (Taco works on their own time frame) Still waiting on my graphics.

Like I said earlier, the rusty trailer and Bravo drive are gone as of today!!

[SilverBack]

Well, the entire interior just got taken out today. We are totally redoing the interior. The new skins are at the embroidery shop getting graphics put in the as I type.

I will post some interior pictures when we get it put back together in the next few days.

My procharger, Super Chiller and Paul Pfaff fuel injection came in today as well. I already got my IMCO Power Flow manifolds.

[BlownCrewCab]

So, You Got rid of the bravo drive off this boat??? I guess your getting the shorty then?

[SilverBack]

BCC, You are correct! I am getting a much beefed up out drive with a -2 short lower.

[Last Real Texan]

I love this prioject!!!!!!!!!!!!!!!!!!!

Looking forward to the results. Also E mail me some photos of the Procharger Phaff set up
Artifactual@mac.com

LRT

[SilverBack]

Here are a few pictures of the engine build up stash. I will have to post the stuff in 2 or 3 replies.

[SilverBack]

Here is a few more pictures. I am going to have to get the camera and take a few pics of the plenum, throttle body and new AFR 345 CNC'ed heads.

[SilverBack]

Ok....Here are the AFR 345 cnc ported heads and the Paul Pfaff setup.

[SilverBack]

Here is the major part of the engine build up. I should hav the engine out within the week.

[The Hedgehog]

Dang man. You are hammering on it. You will make something happen. I can respect that. It won't be a slow boat!

[SilverBack]

Well...The boat is in Baton Rouge. I took it to David Wade Marine today. They are going to do all of the boat work and dyno work. I will post the numbers from the dyno in the next couple of weeks. You wouldn't believe all of the fine boats that they have there. You wouldn't believe all of the fine engines there either.

http://www.davidwademarine.com/index.htm (http://www.davidwademarine.com/index.htm)


The heads are at Womack Racing Engines/ Womack Head & Block. They do a lot of marine engines and have built half of the Hot Rod magazine Pump Gas Drag engines for the last 5 or 6 years. Rimi Baker is building the long block.

[The Hedgehog]

With those heads and some blower pistons, it will be happy. Are you going to up the boost?

[SilverBack]

Do you think 9 psi is too much? Just kidding. He said that he is going to build the engine to handle 10 psi but I think I will run 5 until I get a good bit of seat time in this boat. You have to know your limitations...Right??

He has a few different pulleys and he is going to try some different things on the dyno. So we will see. This guy really knows blowers. I bet he had at least 10 900 hp+ engines in his shop that were on engine stands and He had two boats with Ilmors and several with the huge mercs. I am just a hick from Mississippi but I have been around a lot of high end racing type stuff and I have never been any place any more impressive than his shop. I bet he had over 50k worth of Herring props just setting in his shop. I know some of the guys down in Miami and elsewhere are probably laughing it up reading this. I know it wasn't 188th street but it is as close as I have been!

I will try to take some pictures when I go down there next week to take another load of parts.

Oh yes Big ZX....He works with Paul Pfaff and this injection system was a custom built piece. He is going to do the tuning on the dyno and Paul Pfaff will make any adjustments to the computer.

[BigGrizzly]

Looks good from here. I am conservative. We have built many big blower motors including and some 640cid Donavon that run 900hp on 87 octane. I think you can boost your self out of durability.My Criterion runs 4.7 PSI and I have a ton of hours on it. Looks like your putting some dollars in to this. Good luck and may the gremlins never find you.

[SilverBack]

Thanks Randy!! It is good to hear from a guy that has been there and done that. I know that you have a wealth of experience with blown engines. I was thinking 5 psi would be the sweet spot for me.

Now if some of the guys that have played with raising their X would chime in. The engine is out and the time is NOW!!!! It is time to do it or not. I only have a few days to make the decision to pull the trigger on raising the X and/or going with the extension box.

Right now this is the way that I see it. I am 9 inches from prop shaft to the bottom of the keel. A -2 short drive puts me at 7 inches below the keel. I am thinking 12 inches back and 3 inches up is where I am going but it would be great to hear a few opinions! I know that you run your drive in the stock location. I promise not to be sensitive if someone tells me something that I don’t want to hear.

Again…THANKS!!!

[BigGrizzly]

Here is your problem. No one Has don the extension box and raised dimension on that particular boat before. A similar boat won't help. In theory the extension box runs in cleaner water. With that boat don't put the prop shaft higher than the bottom of the keel, planing becomes a major issue. Speed is increased but everything else suffers. Never do anything that can't be changed back easily. example an extension box with a 3 inch rise uses the same bolt pattern as the straight one, a shorty can have spacers put in to lower it without re glassing the hull and drilling new holes. If I ever change my out drive to something else I will use a plate or a extension box that goes from TRS to conventional Merc bolt pattern. Following is a picture of an Eliminator cat that has the X on the ragged edge. We worked with Turbo and designed a prop specially for this boat- Maximus and Herring didn't work. Most of the problems were planing issues and top speed handling. We played with spacers but speed suffered. Two years later is a picture of cruising at 108 and and Dan the owner shooting the bull with my son.

[BigGrizzly]

Try it again.

[SilverBack]

Randy,

How much were those props? David had a set of 6 blade Herrings down there yesterday that they had to get custom made with the diffuser rings so long they were 9 inches behind the blade. It was really wierd looking. He said that they really helped that particular boat to not blow the prop out. I didn't reliaze that you handled props like that. We may need to talk very soon. I don't have anything that is even remotly close to what I am going to need on my boat when I get done.

[The Hedgehog]

Try it again.

Man Griz, those props are up there. How long did it take you to get that dialed in?

[BigGrizzly]

Getting it right wasn't easy. the owner was really supportive. When the first set didn't work he looked at me with a smile and said "That is why it is called testing". Since we built the engines we knew where the power and torque was. We all took turns driving to get the feel and make sure someone wasn't driving it incorrectly. The good part is when we got it done he could actually plane at just under 20 mph as opposed to the 52(gps) before. It was sold a little while ago to a man in Tahoe. He flew out here test drove it and wrote the check on the spot. Next time I talked to Dan he asked if we could do a V hull. Dans first performance boat was a 25 Black Widow. It took about a year to get it right because of getting all the players together etc. The Herrings probably cost $4000. these were much cheaper. Your boat won't be anywhere that bad to prop. the real trick is make only one change at a time. With twins making the mirror image prop was the hard part. In this case it was soooo important. Thanks to Turbo for working so hard on it.

[SilverBack]

So what are your thoughts on the box and the X on my boat? What do you think the 12 inch setback will do with this hull? Randy, Where do you start seeing problems when raising the X? What is the least amount of space that you think I can run between my pad and prop shaft and still be safe? Thanks!

[BlownCrewCab]

"You Could" (notice the quotes) With a standoff box Run your prop 2" Higher than the Keel. It would be very similar to having a arneson drive. The draw back is when your only running 1/2 the prop in the water you don't get any kind of leverage to trim the boat for speed, all your going to get is how fast your monster motor can push your wetted hull through water, and when trimming you'll just get a bigger roostertail, not a freed up hull. Which is one reason arneson makes rocker plates. If you can get a box that lets you adjust up and down, with some work you can probably find a happy medium. Testing and Propping are the key. Hey, after you figure this out everybody will be asking you what to do..
(side note) You may be able to run your x real high with a "special high dollar prop" but if you ruin that prop you have ruined your whole set up...I'd try to get the most from production props before basing your setup on a special prop.

[mjw930]

"You Could" (notice the quotes) With a standoff box Run your prop 2" Higher than the Keel. It would be very similar to having a arneson drive. The draw back is when your only running 1/2 the prop in the water you don't get any kind of leverage to trim the boat for speed, all your going to get is how fast your monster motor can push your wetted hull through water, and when trimming you'll just get a bigger roostertail, not a freed up hull. Which is one reason arneson makes rocker plates. If you can get a box that lets you adjust up and down, with some work you can probably find a happy medium. Testing and Propping are the key. Hey, after you figure this out everybody will be asking you what to do..
(side note) You may be able to run your x real high with a "special high dollar prop" but if you ruin that prop you have ruined your whole set up...I'd try to get the most from production props before basing your setup on a special prop.

Actually, as explained to me by a boat builder / racer, a 12" box raised 1" - 3" (depending on the hull) will give you about the same leverage as the current X dimension at the transom. A 12" box at the same X dimension give you a lot more leverage.

As the water exits the transom it starts to move up, placing the drive further back means you can raise it relative to the angle the water is rising. This is the concept behind all notched transom boats.

An Arneson, OTOH, exists the transom at the crank height which is at least 2 FEET higher than the prop shaft on a Bravo 1. Raising the drive 3" doesn't even come close to approximating a surfacing drive.

[SilverBack]

Thanks guys! I had a deal put together to buy an extension box and a dual ram full hydraulic steering. The deal fell through tonight so I don't know what I am going to do. Maybe I should just raise the drive 3 inches and leave everything else alone. My first instinct was to raise the drive and add the extension box. I have a meeting with David Wade tomorrow so I guess we will make some decision by the end of the day tomorrow. Thanks for the help!!

[BlownCrewCab]

Actually, as explained to me by a boat builder / racer, a 12" box raised 1" - 3" (depending on the hull) will give you about the same leverage as the current X dimension at the transom. A 12" box at the same X dimension give you a lot more leverage.

As the water exits the transom it starts to move up, placing the drive further back means you can raise it relative to the angle the water is rising. This is the concept behind all notched transom boats.

An Arneson, OTOH, exists the transom at the crank height which is at least 2 FEET higher than the prop shaft on a Bravo 1. Raising the drive 3" doesn't even come close to approximating a surfacing drive.


There are no drives that exit the transom at crank hight (at least that I have ever seen) without a chainbox or gearbox to lower it to just above the keel. I used the example of the arneson and the 2" because he (the OP) seems to want to go really high. I Know how far back a box puts the prop and where and how the water gets to it ( I'm not putting you down, I Promise) I worked on the "Very First" Boat to ever have a standoff box and a merc drive (actually 2), I Know he wants to go as high as he can and get all he can while still being safe, his problem is the drive is way too low as it is, so raising his X is a must especially if he adds a box.

[SilverBack]

Michael,
How do you think my boat would act if I leave off the box and go with the -2 imco drive and raise the x 3 inches? Thanks!

[BlownCrewCab]

I think just a 3" high X and a standard drive would be conservative seeing how you have a flat pad. The 3"X and 2" shorty should be pretty close to what you want, If it ends up 1 or 2" high you can spacer back down. (25-30 min job to go back down) It'll save you the money from buying a box to try this first, then if needed buy a box later. but just raising the X means you can allways spacer down pretty easy...

[SilverBack]

Michael,
Thanks a million. That is what I will plan on doing then. Like you say. I can always spacer down or change the -2 lower for a standard one and be back within 1 inch of where I started. I really think that the boat will like the higher X. The drive is SO deap now. Thanks again!

[SilverBack]

I am going back to Baton Rouge tomorrow. I am meeting with David Wade. I talked to the engine builder today and he really wants to go with an aftermarket hydraulic roller. He thinks with the AFR heads and the way we are building up the bottom end and stroking it to 540 ci that we should go with a little bit bigger cam. He thinks we can get about 850-900 HP with the bigger cam and 5 PSI of boost. I guess we will know by the end of next week. We should be on the dyno by then. I can't wait to get David started on the hull. I think he wants to blueprint the hull and raise the X. I know he wants for me to add the box but I think I will just wait since the deal that I had on the box and steering fell through. I can always do it later.

I will try to take some pictures tomorrow.

[mjw930]

Not to throw cold water on this but are you sure the hull and stringer layup can handle that much power?????

[SilverBack]

We are beefing up the transom and stringers. That is why I wanted to raise the X now. We are going to be doing glass work anyway. I don't know if the IMCO Xtreme advantage SC drive will hold up or not. I am sure that I will be babying it though.

[SilverBack]

I think that I will keep the blower pulley that I have for now anyway. It should only put out about 3-4 psi of boost with a 540 and a bigger cam. So the HP should only be around 750-800.

My hull is a little thinner than my other Donzi's though. This boat actually weighs less with the 502 and Bravo than the 23' Ragazza did with a small block and an Alpha. It only weighs 3200 lbs. When you bump the hull on this 25 with your fist it moves. The Ragazza is rock solid. I would have thought that the 25 would have been heavier by a good bit but it is not.

[mjw930]

We are beefing up the transom and stringers. That is why I wanted to raise the X now. We are going to be doing glass work anyway. I don't know if the IMCO Xtreme advantage SC drive will hold up or not. I am sure that I will be babying it though.

Cool, then you have it covered. I think the drive should be ok considering the weight of the boat. A friend has installed a couple of these behind some serious blower motors in dual applications on 8000 lb + boats and they seem to live pretty well.

[The Hedgehog]

I fully expect to check this thread tomorrow and find out that you have gotten some sort of a deal on a 1075 or maybe a custom built 1,200hp motor with a #6 or even an Arneson:eek!:

You run with things even faster than myself. :smash:

I still think that is a smoking deal on that blower.

One thing is for sure, with that much hp, something will happen and happen fast!

[SilverBack]

Bill,
You are cheating!! I may as well go with a #6 dry sump!! David Wade wants me to go with a 4x4, extension box and full hydraulic steering.

He says this thing is going to be very fast for a DONZI!! What does that mean?

He also says that he has never seen a Donzi with a hull like this. Not only does it have the little pad bottom but he thinks the hull is not made like a standard Donzi. Has Donzi ever used some kind of different material for the hull? This thing is very thin and it is pretty light. This is either going to be good or bad.

He is going to customize my extension box and weld an exhaust coming out the bottom. So I will still be able to use the Silent Choice.

He is also going to raise my X 3-4 inches. So I guess we will find out what is going to happen.:crossfing:

[BlownCrewCab]

Keith, So you found another box??? or is this the same one? Is it adjustable at all? Do you have your shorty drive yet? if so maybe you can have them mount the drive to the box and hang it at the back of the boat and mock up the installation (before any glassing and cutting), start checking with a straight edge and see how much prop will be in the air, and see if it's all going to be what you want, Just check it over (and over) Maybe even post up some pics so we (the board) can review. ( I Believe it's gonna kick Azz) may even be the fastest boat at the next meet...:eek:

[The Hedgehog]

Fast for a Donzi?

Hmm. He may be referring to the fact that Donzi builds them strong but not the fastest. For the size and power, names like Fountain and Velocity both build faster boats. That does not mean that they are better all around boats but both of those two are tyipcally faster. Now does that mean that a 35 Executioner can beat a 35 ZR in the ocean. Probably not.

Pantera builds a serious 27 foot offshore boat as well. In the smooth water a comparable size (or I should say length) Fountain will smoke it. Throw out some 5 footers and you will get a different story.

Now for my ZX, it will dine on a steady diet of Fountains and Baja's. :smash:

I think that some other boat companies build a nice looking boat but my preference happens to be Donzi and I feel pretty good about it.

[SilverBack]

Michael,
I don't think it will be nearly that fast. Those little classics really fly!! It does keep getting to be more and more to this build up. I started out trying to get a boat that would cruise at 60. Now it looks like I am going to end up with a ZX that will have 850 HP and a BAM transmission and a IMCO 4x4 drive that is a total of 6 inches higher than stock. David Wade is doing all of the work. I hope that I can get some pictures but the boat is 110 miles away. I really think that he knows what he is doing though. There is no way that those guys are letting him work on those 400k-600k boats if he wasn't. He says that we could go up as much as 2 inches below the keel and still make it work. He says 2-4 inches below where we will be is still very conservative. I hope he is right!! He showed me a Formula and an Eliminator that has the drives way up above the keel.

[SilverBack]

Bill,
I may have said that wrong. He was talking about how a Donzi is usually built very heavy and also built to handle rough water better than most boats. Because this is the case, it is like you are saying. Some other boats are faster in smoother water. He was saying that because my boat is made a little lighter and has that little pad that it may run in smooth water more like a Fountain or Eliminator. He is the throttleman for the popeyes boat so he is more into speed hulls, cats and the such. I don't have any seat time in a boat like this and I have a lot of learning to do so I can assure you that I will not be the fastest thing going! I work as a consutant and if I don't work I don't get paid. I have to err on the side of safety.

[Last Real Texan]

I said it once and I'll say it again......love this project !!!! Keep us posted on what's going on.

Bryan

[SilverBack]

OK....let's change the subject for a second! I just got back from meeting with my upholstery man. He has the first bolster done and a couple of other things. The embroidery shop messed up one piece that goes in my strip and they are doing some new pieces tonight. I will post a couple of pictures.

They started to break my engine down today and the fun is about to begin. I also got my custom cam back today. Oh yes one other thing. If you see any engine stuff with a PFM logo....That is not Paul Pfaff. It is PFM the company that started Super Chiller. They are out of business now but they sold the Super Chiller line to Teague. Just to let you know if you ever come across this stuff. There is a company called boost power that has all of the software for their computers.

[SilverBack]

CarlC,
Thanks for the comments. I am glad you are getting something out of the thread. I am too. Good to hear from you!

[SilverBack]

Ok, they broke the engine down today. It had been gone through not too long ago. I got my MPI fuel injection and brought it back to the house. I am selling it and the F.A.S.T. 3. The manifolds were toast. They had fits getting those bolts out. RUSTY. Everything else is like new except those manifolds. They went straight into the scrap iron heap. The cylinders had almost no wear and the engine builder said the engine had all fel-pro gaskets. It did have the correct 4 bolt block, forged steel crank, rods and forged pistons. I got a hydraulic roller from Cam Motion. The heads are together. I should have some pictures in the next few days. We are going to the Dixie Nationals horse show for the next few days so it may be Sunday before I get the pictures up. The engine is supposed to be on the dyno by next Friday so maybe I can post some good numbers by the following Monday. They were taking the transom assy. out today and the gimble. Getting ready to raise everything and for the new 12" box and transmission. Oh yes took them the rub rails and got the graphics in today also. The interior guy has the two bolsters ready and all of the cabin upholstery is ready to go as well.

[SilverBack]

I had some good conversations last night with some guys. They brought up some more questions and gave me a few answers.

First the question. They have the engine out and the transom is just setting there with a hole in it. I was talking to the guy that has the IMCO 4x4 setup and he asked me if I was spending this much money on a drive and raising the X and was going to be pushing that much HP. Why not just go with an Arneson ASD 7? So what do you think? I need some answers pretty fast so fire away. Give me your 2 cents. I will appreciate it.


Second the answers. I finally tracked down someone from PFM. The guy that designed the system that I have. He said that it is called the PFM S/C Gorilla. He knew the boat that my system came off of and he said it was one of the last ones that PFM had done. HE told me that the system has 85#/hr injectors and he is sending me a programmer box. The guy had this on a 28 foot boat with a 454 mag. The guy had an M-1 to start with, with the Procharger intercooler. HE was running 6 psi of boost but he kept having trouble. He had been through several of the M-1's and a couple intercoolers when he got to PFM. They had this system and put it on his boat. He could not get it to put up but 2 psi but had more power than before. This guy claims it is because of the restriction in the Procharger intercooler and the MPI. He says that the guy got this M-3 and the 5 psi pulley and he still only had 3-4 psi but the boat even ran better than before. Then he got the 7 psi pulley and he ended up with 4.5 psi and just left it there because the boat was doing more than he had ever expected. He had a 28' deep V and he was doing 85 GPS on an otherwise stock 454 MAG and a stock drive. This guy just sold the boat and he took this system off because the guy buying it didn't like the noise of the procharger. They put a different intake and a carb and it now runs 61 GPS. I wonder if they had a bad boost gauge?? 24 MPH sounds like a lot from a Procharger and a fuel injection setup. I guess we will see in the next month or so......

[BlownCrewCab]

You would have to patch the hole for an Arneson also. Your just moving the hole up staying with a bravo.
with a high mounted bravo you'll still get more trimability than a Arneson, But you may not need the positive trim.the arnesons are pretty much bomb proof, you'll only have to buy it once. Both have their good points..

Do you have a transmission?? That could be your answer. bravo doesn't need one, arneson does.. (never mind, I re read your post) you do have a tranny, and a box, go with that....summers coming..

[The Hedgehog]

Tex and I were discussing how long it was going to be before you got interested in the Arneson thing. They are very cool but you will spend some time dialing one in. I agree with Crew cab, summer is coming.

I will give you a shout re the Procharger. Boost levels are largely driven by how much an engine will flow. You can take a stock system with 5 lbs and drop the boost by using a bigger cam and heads. Intercooler efficiency and cooling will have an effect as well. Your ultimate boost levels should be taken at the manifold. That is after everything has happened.

[SilverBack]

Thanks Mike and Bill!

I don't have a box or transmission yet. The 4x4 uses a transmission in the box just like the Arneson. The Bravo conversion Arneson uses the same hole though.

It just sounds like once I go one way or the other I will be pretty much committed to that route. One of the guys I talked to last night spent $36,000 on 2 Arnesons for his 29 Cigarette and couldn't even plane out for the first 3 days he had it on the lake. He said it was all year really getting it to run right. It had 2 small blocks when he bought it. It ran 71 MPH. He put 2, 500 EFI's with Vorteq superchargers in it and got 84 mph out of it. HE put the Arnesons on it and he says he is now doing 108 mph. He says he has about 1,350 HP. He said he wouldn't trade them for anything now but had the worst summer of boating in his life 2 years ago when he installed the Arneson. He said that he had been through close to 25k in custom props before he got it right. He has also become freinds with Rick at Arneson and he gets drives that are 3 weeks old back on a regular basis. I guess those folks didn't have that much patience.

I don't know about getting into all of that. Well, I guess I know that I don't want to get into all of that.

[mjw930]

Thanks Mike and Bill!

I don't have a box or transmission yet. The 4x4 uses a transmission in the box just like the Arneson. The Bravo conversion Arneson uses the same hole though.

It just sounds like once I go one way or the other I will be pretty much committed to that route. One of the guys I talked to last night spent $36,000 on 2 Arnesons for his 29 Cigarette and couldn't even plane out for the first 3 days he had it on the lake. He said it was all year really getting it to run right. It had 2 small blocks when he bought it. It ran 71 MPH. He put 2, 500 EFI's with Vorteq superchargers in it and got 84 mph out of it. HE put the Arnesons on it and he says he is now doing 108 mph. He says he has about 1,350 HP. He said he wouldn't trade them for anything now but had the worst summer of boating in his life 2 years ago when he installed the Arneson. He said that he had been through close to 25k in custom props before he got it right. He has also become freinds with Rick at Arneson and he gets drives that are 3 weeks old back on a regular basis. I guess those folks didn't have that much patience.

I don't know about getting into all of that. Well, I guess I know that I don't want to get into all of that.

I think you've answered your own question. Unless you have an unlimited budget and unlimited patience doing the Arneson isn't for you.

[SilverBack]

MJW,
You are right! I guess that I did. I did run across a brand new Arneson 8 for $8,500 and it was complete with steering rams and trim rams and a transmission. It has a 10" drop. I don't think that I want to go down that path though. So I guess that is a no go for me. I have enough stuff going on and enough stuff to have to worry about. I just found out that my next job starts on Tuesday and it is way down out of South Texas. It will take me all day Monday to get there. I have the people showing up Monday to build the new shop so I guess it will be the K.I.S.S. (Keep It Simple Stupid) method from here on out. The boat should be put back together and ready to take out and do some prop testing when
I get back from this job.
Mike Brown introduced me to a Mercury, Drive and boat GURU named Justin today. He is going to help me a little in the next few days with my X and hull setup. Since I have a hull that must be a one of a kind it may take some glass work to get things tweaked along with the prop testing. This sounds like a lot of fun. I just hope that I do not have to work over during AOTH to pay for it all!!!

I think this boat is going to be great when/if I get it ironed out. Thanks for everyone’s help!! I would not have gotten this far without Bill, Mike, Bryan, Randy and MJW you have helped a bunch too. Buzilla at least you warned me that it was going to cost a fortune! Thanks a million!!! I look forward to taking a spin with each and every one of you at one point or another!!

[The Hedgehog]

OK....let's change the subject for a second! I just got back from meeting with my upholstery man. He has the first bolster done and a couple of other things. The embroidery shop messed up one piece that goes in my strip and they are doing some new pieces tonight. I will post a couple of pictures.

They started to break my engine down today and the fun is about to begin. I also got my custom cam back today. Oh yes one other thing. If you see any engine stuff with a PFM logo....That is not Paul Pfaff. It is PFM the company that started Super Chiller. They are out of business now but they sold the Super Chiller line to Teague. Just to let you know if you ever come across this stuff. There is a company called boost power that has all of the software for their computers.


That is pretty work

[BlownCrewCab]

Did Justin give you any good info? He's one sharp dude. He's a virtual walking/talking Mercury/Mercruiser Knowledge base.

[SilverBack]

Bill,
Thanks!

BCC,
Justin is a very sharp dude!!! I am very impressed with him. Bill and Bryan this is a guy that you need to get to know. He knows his stuff. After talking with him I have decided to just put my tuned down 800 HP engine in the 25 ZX and put the IMCO SC on it and have fun! Then I will see where I am. It is not that big of a deal to pull the engine again if I want to go with the box later and I can always sell the IMCO and go with a bigger drive. The only thing that I don't know if I am going to do is rasie the drive any more. That may be a better job to do later. I have a feeling that I will be as fast as I want to be until I get a lot more seat time with this boat.

Justin thinks if I lower my boost to 3 lbs that I will be in the 650 to 700 HP range and the drive might last for a while. I should be able to get in the 70 MPH range and that should be plenty.:wink:

[The Hedgehog]

Bill,
Thanks!

BCC,
Justin is a very sharp dude!!! I am very impressed with him. Bill and Bryan this is a guy that you need to get to know. He knows his stuff. After talking with him I have decided to just put my tuned down 800 HP engine in the 25 ZX and put the IMCO SC on it and have fun! Then I will see where I am. It is not that big of a deal to pull the engine again if I want to go with the box later and I can always sell the IMCO and go with a bigger drive. The only thing that I don't know if I am going to do is rasie the drive any more. That may be a better job to do later. I have a feeling that I will be as fast as I want to be until I get a lot more seat time with this boat.

Justin thinks if I lower my boost to 3 lbs that I will be in the 650 to 700 HP range and the drive might last for a while. I should be able to get in the 70 MPH range and that should be plenty.:wink:

Well it certain that you are looking at both sides of the picture. If you do it that way it should be bullet proof. That being said, if you are doing all that engine work, I think it would be a shame to stop at 3 lbs. I would do with 5lbs minimum. The boost on a centrifugal blower comes on higher in the power band and is easier on drives. 5lbs is not that hard on the engine either. You can always back off the throttle. You also have a fairly light boat.

Tex is getting ready to up the ente in his to the high 700's with his new pretty new Brodix heads and more boost. He is using an IMCO sc as well on a heavier boat.

That being said, we have both been told (by different sources)that we are in the power range that it will not be a matter of if we are going to break are drives but when we are going to break our drives!:hangum: Don't you want to join that club?:eek!:

[SilverBack]

You are right as usual Bill. When I talked with Justin he said he has seen several people with Prochargers and Vortec blowers that have well over 700 HP running regular old 1.50:1 Bravo's. With no mods at all to the drive. Just stock gears and everything. He said the main thing is how you drive them and he feels that maybe they are just getting lucky with it. I guess that is like Grizz having all of that power and running that KC. I don't know what he has done to the drive but I know he has been around and KNOWS what he is doing and how to take care of his drive. I am sure that he is not getting all wild with it. I am not real sure about that but I wouldn't think that he would be abusing his drive and it has held up for him. He says that the SC has a pressed in tower and the XR has a threaded tower. The XR has more needle bearings and the SC has larger but fewer bearings. He says they both have there week points so one may be better for one driving style and the other better for another.

I am not going to be doing any wave jumping and he says that is the hardest thing on a drive with big power. Loading and unloading huge power is what flexes the gear set and the tower can not hold them in perfect alignment and wham broken drive. He says he has had friends that have cratered #6 drives with 900 HP. It just depends on how you drive your boat and where your power comes in. He says it is torque and loading/unloading that has the biggest effect on killing drives.

[SilverBack]

Bill,Mike and Bryan,
I got some pics emailed to me offshore today. You know that I don't like to go with stock stuff either but David wanted to stick with the stock balencer. So we did. These are some pictures of the crank on the balancer and the heads. After all of the talk about ARP studs he went with ARP bolts....go figure!!

[SilverBack]

Here are some more pictures! It is going to the Dyno tomorrow:crossfing:. David should be out testing props next week!:tongue::tongue::):tongue::tongue:

[The Hedgehog]

You got it coming together nice and quick. You should make some power. You going to clear coat the heads or use a metallic finish? You should feel pretty important with that under your hatch!

What size injectors are you using? I can't remember if your setup already had big injectors. How much power are you looking to make?

Are you going to use a high volume oil pan?

[SilverBack]

It is nice having a brother that is always building toys. People seem to jump right on your stuff too. :doh:

The heads and intake and valve covers are going to be cleared. The super Chiller and plenum and throttle body are already polished. I don't know if they did the clearing on the valve covers yet or not because I am stuck out in the Gulf of Mexico.

The Gorilla setup already had 85# injectors. We sent them off and had them cleaned and tested.

I get different stories on the HP. The engine builder seems to think 850 - 925 HP at 5600 to 6,000 RPM. David seems to think 750 to 850 HP at 5,000 to 5,400 RPM but he doesn't know the exact cam specs. That is with 5 PSI of boost. We will know tomorrow. David says he thinks that this 6 blade Herring with 31p is going to be the best performer. If that is the case with 8 % slip and 1.36:1 ratio....you do the math. I think he is thinking more power but I think he is sand bagging me on HP projections a little.

[The Hedgehog]

It is nice having a brother that is always building toys. People seem to jump right on your stuff too. :doh:

The heads and intake and valve covers are going to be cleared. The super Chiller and plenum and throttle body are already polished. I don't know if they did the clearing on the valve covers yet or not because I am stuck out in the Gulf of Mexico.

The Gorilla setup already had 85# injectors. We sent them off and had them cleaned and tested.

I get different stories on the HP. The engine builder seems to think 850 - 925 HP at 5600 to 6,000 RPM. David seems to think 750 to 850 HP at 5,000 to 5,400 RPM but he doesn't know the exact cam specs. That is with 5 PSI of boost. We will know tomorrow. David says he thinks that this 6 blade Herring with 31p is going to be the best performer. If that is the case with 8 % slip and 1.36:1 ratio....you do the math. I think he is thinking more power but I think he is sand bagging me on HP projections a little.

I dunno about the 8% slip. That is up there with cats.

If you can pull 18% slip at 5,400 you will be well into the 90's. 85 lb injectors are huge. I will be using somewhere between 55 to 65lb. Brian found some 55's that can handle lot's of fuel pressure. Eddie is liking 65's and can get the pulse width down enough to make it idle good. Eddie makes the call on that considering that he has probably forgotten more about engines than I will ever know! I read some posts from a guy with a 540 that ran into the 900 hp range with similar size heads that had good results with 65's. He is the guy that ultimately turned it over 1,000.

One thing for sure, you will be hauling ass! What kind of steering are you using to keep that beast in a straight line?

[BlownCrewCab]

If you can spin that 31 above 5400 with a 1.31 gear you'll be almost twice as fast as it went before, Thats 2 (two) times as fast, Thats frigg'n fast. Family boat huh? A Family wearing Lifeline Jakets and helmets. What class are you going to race? J/K But it's going to be fast. Is the steering going to be done for prop testing?

[SilverBack]

You are right 85# is huge ...I guess that is why they call it a Gorilla!!! I did miss a 1 on the 8%..Sorry. 18%. I am really getting excited about this dyno run tomorrow. Rimi never misses by much on his engines. I think he has talked David into taking it to 6k and see where the HP curve is. I know one thing I am going to need some seat time if I am going to turn 6k with that Herring prop!!

Steering..what steering. It is all stock!! That is fine isn't it? I haven't done that yet!! It is looking like a Dry sump #6. Right now I have an IMCO Xtreme SC with
-2 IMCO lower with the big shaft. David is still working on what to do. 4x4...#6.... who knows. David’s racing buddies regularly get rid of that stuff for really "cheap". I have just left that in his hands. We will see. Hey...he is the one testing it not me. He flipped his boat going 130MPH last year so this should be no problem. Right???

I think we will be putting a dual ram full hydraulic on it. It is still up in the air????

Did you have to bring up STEERING and DRIVES????

[SilverBack]

Michael,
Do you think matching Donzi logo helmets would be ok for the girls? J/K

I am going to be in so much trouble...I told the wife that I was just rebuilding the engine because the guy down there in FL hit too many manatees in it. When I got it the old Bravo was locked up and the engine would not turn over when we got it home. I have tried everything I can to keep my captain call but I am going to have to give up the fight I guess. She is going to kick my rear when I fire that sucker up. By the time I put a box and hydraulic steering on it the swim deck will be useless. My ladder would hit the steering. I am going to have to fab a stainless or aluminum add-on deck to go behind the swim platform like on a Cig. (Here come the comments!!)

Yes this is a family boat. :bonk:Bill just got me carried away with all of this performance stuff. :hangum:It is all his fault.:mad:

Oh yes..besides fabing my new swim platform extension, I need to mount my little hooks that you hook the tube rope up to.

Michael,
Would you like to come down and go tubing some time?? It is a family boat!!!!

[SilverBack]

BIG GREEN ZX??????

Bill,
I am slow and I am from Mississippi so let me ask.....Did you sell the BGZX?? Why have I not heard? I was just looking back through this thread and wham it is gone from your signature.

Bryan,
I am sure that you have heard about this already right....Did this happen when I was at the Dixie National Horse Show???

Bill,
Do you plan on spending any of the proceeds from this sale to do any further mods to the BAZX??? (Bad A$$ ZX)

If so...Someone needs to tell Ted (Mr. X) not to bother with the Ilmor...Tell Geoo that he did the right thing when he got rid of the 18!!


Do I smell arnesons and M-4's or M-5's???

Maybe I am just getting ahead of myself..I have a tendency to do that.....

[The Hedgehog]

Michael,
Do you think matching Donzi logo helmets would be ok for the girls? J/K

I am going to be in so much trouble...I told the wife that I was just rebuilding the engine because the guy down there in FL hit too many manatees in it. When I got it the old Bravo was locked up and the engine would not turn over when we got it home. I have tried everything I can to keep my captain call but I am going to have to give up the fight I guess. She is going to kick my rear when I fire that sucker up. By the time I put a box and hydraulic steering on it the swim deck will be useless. My ladder would hit the steering. I am going to have to fab a stainless or aluminum add-on deck to go behind the swim platform like on a Cig. (Here come the comments!!)

Yes this is a family boat. :bonk:Bill just got me carried away with all of this performance stuff. :hangum:It is all his fault.:mad:

Oh yes..besides fabing my new swim platform extension, I need to mount my little hooks that you hook the tube rope up to.

Michael,
Would you like to come down and go tubing some time?? It is a family boat!!!!

Your killing me. Swim platform extension. That's pretty good!

Manatees. I had the problem with Gators. I had to get a little tune up that required all of these big boxes from this company called ATI.

[The Hedgehog]

BIG GREEN ZX??????

Bill,
I am slow and I am from Mississippi so let me ask.....Did you sell the BGZX?? Why have I not heard? I was just looking back through this thread and wham it is gone from your signature.

Bryan,
I am sure that you have heard about this already right....Did this happen when I was at the Dixie National Horse Show???

Bill,
Do you plan on spending any of the proceeds from this sale to do any further mods to the BAZX??? (Bad A$$ ZX)

If so...Someone needs to tell Ted (Mr. X) not to bother with the Ilmor...Tell Geoo that he did the right thing when he got rid of the 18!!


Do I smell arnesons and M-4's or M-5's???

Maybe I am just getting ahead of myself..I have a tendency to do that.....


The Big Green ZX has been sold to CJMike. He will pick it up when the roads to Minnesota become navigable again with a boat trailer. I am very glad he did take it when he came down. They barely made it back alive without a boat!

I guess that I will need a new name and maybe avatar. I will probably stay with the porn theme....... :shocking: Maybe I should get an Arneson. They have even longer shafts. That way I too could render my swim platform useless. Maybe I could rig up a diving board to the back. That way people could dive out and clear the drive.

I was originally thinking I would put the money back in the bank but now I have realized that most of it will go to mods on the new boat:hangum:

[SilverBack]

Jokes?????

I have serious troubles and all my freinds can do is make jokes!!

Diving boards??

I need to get the people back in the boat not find a way for them to get out!!!

I know we can come up with something good. There has to be some modiification that we can make.

This has to stay a family boat!

[BlownCrewCab]

Family Boat..... That still cracks me up:rofl:You'll be able to tell Kieths Family, Their eye lids and Hair will be blown back. And they'll all be smilin:biggrin: Big time. (Just messin w/y Keith, It's going to be Nice)

[SilverBack]

Michael,

Does that mean that you don't want to go tubing? Where do you get those head phones like on the big Z boats?? I think I am going to need some.

[BlownCrewCab]

I'll Go Tubing...As Kids we would Jump out of the boat going 30mph, Then 40mph, then 50mph and so on, Lucky for us the boat topped out 65ish. So I'm familiar with smashing, skipping, sliding, Choking on water. I'll just make a bigger splash now...

[SilverBack]

Michael,
That kind of stuff hurts a whole lot more when you get older! Healing up is not any quicker either!!!

I guess if you are up for the tubing I had better get started on my swim platform extension plans. This boat is so light it sits way up out of the water. I don't know if we would be able to get you back in without a ladder!!:eek!:

[yeller]

Man, you're goin' to town on that thing! This is one of the best threads ever. I love this stuff. I've always followed the build ups of Last Real Texan and BGZX and enjoyed every minute of it. True, not a lot of people here comment if it's not in a Classic, but I'd be lovin' this even if it was in a Bayliner. HP is HP baby, I don't care what it's in. Stang, I thought you were just BS'n when you 1st came on board. Talking big, about doing this and that, but you're backing it up. Way to go! It's nice that LRT and BGZX have some friends to play with now. :tongue:

On a side note: BG, weren't you planning on putting a procharger on your V6. I thought I read that somewhere. I know it's not a V8, but I was really, really looking forward to the results of that test. I love the V6, I think it's a great motor for its size, just needs for someone to make a good set of heads for it.

[The Hedgehog]

Man, you're goin' to town on that thing! This is one of the best threads ever. I love this stuff. I've always followed the build ups of Last Real Texan and BGZX and enjoyed every minute of it. True, not a lot of people here comment if it's not in a Classic, but I'd be lovin' this even if it was in a Bayliner. HP is HP baby, I don't care what it's in. Stang, I thought you were just BS'n when you 1st came on board. Talking big, about doing this and that, but you're backing it up. Way to go! It's nice that LRT and BGZX have some friends to play with now. :tongue:
On a side note: BG, weren't you planning on putting a procharger on your V6. I thought I read that somewhere. I know it's not a V8, but I was really, really looking forward to the results of that test. I love the V6, I think it's a great motor for its size, just needs for someone to make a good set of heads for it.

Yes, we are definately happy to have someone to join us on the stupid human in boat tricks! I was not concerned that Keith would back down. I know the type. He reminds me too much of one of my whitewater Kayaking friends. The guy started in Class II in a canoe and was running Class V by the end of his first year. Oh wait, I think I did something like that too.

Ah the V-6! Tex solved the head problem. They are ported and punched out with bigger valves. Those guys did some pretty work. Now I just need to shame my recently retired father to step up to the plate on the rest of it. He will. I am thinking that if he comes to AOTH, it will be done.

[SilverBack]

BAZX,

Gaffrig and CMI make switchable tips. Who else makes them? I need to fine the best ones made(quietest) That is the only option that I have left. What diameter exhaust do you have? What size are your tips?

If I can get this figured out I will almost be done with the setup for now (except for the Swim Platform)!!!

[BlownCrewCab]

What kind of exhaust do you have now? ( I'm sure it's in the thread but my computer is so slow I Don't dare go "Back" anything). are your pipes coming out under the swim platform? Or on top? You can hide some big mufflers under a swim platform (Or stainless Wing/Deck) at this point having new tailpipes made isn't a big deal and you can have what ever diameter you want. Back to your "Ever heard a 900hp motor" well Hear one through some 6" or bigger Pipes, now thats happy time..
but have them exit under the swim platform (Or stainless wing/deck) and get some good big flow mufflers and your set. Viola....

[SilverBack]

OK Mr. Brown....I have Corsa Captain Call with the electric actuators. I did have anyway. That will not be going back in. It is going to have to be a switchable tip setup.

Tell me your thoughts on the stainless extension thing you are talking about. I am very interested!!

[SilverBack]

Sorry Michael.
The exhaust comes out below the swim deck. My Ragazza came out obove the swim deck and it was very loud even with the 5.7.

[BlownCrewCab]

Great, If it comes out under you can have as big a muffler as you want and it wont be unsightly. do you have tail pipes for the manifolds you got?

Did they get to Dyno it yesterday?????

[SilverBack]

They used some short risers for the corsa setup. we are going to get the longer taller ones to go in the boat. that is why I am trying to get this exhaust thing figured out. There will be some ordering going on Monday morning. Look at my signature. That is with 4.5 psi. I have a little left to go though.

[BlownCrewCab]

Good God Man, Your Gonna need a Bigger Boat....890hp Wow

[The Hedgehog]

890? So it hit the dyno. That is huge power. You will be hauling some groceries with that. Your boat will have an unmistakable sound.

Back to the tips. Like Micheal says, you can put some big cans under the swim platform and it looks fine. I hooked mine up to the Rex marine tips with some kind of super flapper. If you go with a cheap internal flapper, your beast will blow it out the first time you stand on it.

I am pretty sure that the stainless packing around the tips helps mellow the tone even with the switch open.

[SilverBack]

Bill,

I was just responding to the thread about AOTH and it hit me that I have no real experiance driving this type of boat. I have never driven an i/o over 65 mph and it ran out as smooth as glass. I hope I get a handle on it before AOTH. That would be bad!!I think I am going to have to get you or Michael down here before then for driving lessons.:bonk:

[yeller]

Good God Man, Your Gonna need a Bigger Boat....890hp Wow:worthy::worthy::worthy: Very nice! Can you scan the dyno sheet? 890 at what rpm? What's the torque? Holy crap!....you're pulling 900hp and you don't even give us details. :fire:

[SilverBack]

I can't give everything away!!! There are sharks lurking in these waters!

No...I am at work out in the middle of the Gulf of Mexico. I am sure that I will post something but it may be a few days. That is why I didn't make a big production out of it. We have decided to make some last minute changes. My engine builder is good friends with my older brother Mr. Go fast and Mr. Money bags. He is the one that gave me the AFR CNC'ed heads. He also helped with the machine work. He is also the one that REALLY knows how to drive a fast boat. Don't get me wrong this is my boat he just thinks it is a cool project and doesn't have time to do one of his own. (He is too busy making money all of the time.) He hits me up with the fact that he has a 698 CI aluminum block short block just sitting around doing nothing. He sold the project that he was going to put it in. I told him that I am going to be faster than anyone that I have heard of with this hull anyway. On top of that I am going to crush drives if I am not careful. I could imagine what a 698 CI blower motor would do.

Then to further complicate things. I just made the decision to add the 3 inch rise standoff box. We are going with an IMCO. Then the steering. It goes on and on it seems.

On any account I have decided to scrap my Q+Q and this has led to getting longer taller risers. I think we will go back to the dyno after we install those and see what we see. Thanks!!

[BigGrizzly]

Have fun-been there and done that. With that HP you are going to have to use CMI tube hedders or E-tops at the least. Guess I'll be talking to you when it comes to props. One more suggestion, don't show your wife the check book!!!

[SilverBack]

Grizz,
I haven't talked to David my tuner since they did the dynoing but I have IMCO Power Flow manifolds. He did say that he wanted to change the risers but didn't say anything about going to a header. Are you talking about reversion reasons or backpressure? IMCO says these things are good to 1200 HP. Tell me what you know...I don't need to buy any more lessons. All and all this is a very tame engine. I think that you said somewhere that yours has done very well living at 5 psi. What kind of power do you make at that boost level?

[BUIZILLA]

890 hp on pump gas is a BIG number..

[SilverBack]

Buzilla,
That is a big number!! The only person I got an email from was my brother and I don't have phones out here for another week and it is killing me. I have not heard from the engine builder or the tuner.

My brother had a couple of small blocks that made 1000 HP on pump gas and 1400 on Nitrous. You can Google him if you would like: Charles Jordan Pump gas drags HOT ROD Magazine.

Rimi Baker the engine builder is a master at building pump gas engines that make huge power. He has 2 or 3 of the top 10 at that event every year.

Like I said 890 HP out of a blown 502 with all of the tricks of the trade some of the best flowing non Pontiac heads on the market is not that big! These things flow right at 400 cfm after the CNC porting.

Just wait until I put my 20 gal Fuel cell in there for my race fuel with my progressive nitrous.

It is good to hear from you though BUZILLA....I have been hoping you would jump in here and help me out with some of your advice!!

You are the MAN!!!

[BUIZILLA]

you buy any spare upper drives??

IMO, you might want to s.l.o.w. up a tad and re-think a couple things..

[SilverBack]

OK..I have an IMCO Xtreme SC with a -2 IMCO lower right now. I am looking for a good used #6 right now. I was going with an IMCO 4x4 but the deal fell through. I am bidding my time while a deal comes about on a bigger drive and transmission.

Give me some specifics!! I want to know what your thoughts are exactly! Don't worry about hurting my feelings. I have thick skin.

Thanks again...like I said at the first of this thread. I would love to hear from you guys that have been there and done that. I don't care if it was in a critter or and x-18 or a 22C. It doesn't have to be 100% accurate or correct to my hull. I would love to hear from you classic guys though. I am sure that it would help even if you aren't!!

Thanks for jumping in here!!

[BUIZILLA]

IMO, and i'm sure some others will disagree with me, your doing wayyyyyyyyyyyyyyyyyyyyyyyyyyyyyy too much at one time. You have NO seat time in this hull. Your dumping mega power into a hull of possible unknown quirks. You've never owned, or even driven, a boat with this hull combo or power setup. In fact, nobody has...

with that thought in mind....

your in seriously uncharted waters..

be carefull..

VERY carefull..

take your time..

it's YOUR boat and YOUR money, if YOU want mufflers then buy GOOD and EFFICIENT mufflers...

HTH

[SilverBack]

Thanks for the advice!! Keep it coming!! You are right about the seat time and going into no man's land with this hull. That is why I am not going to be the one putting this thing through its paces. I have a guy that is an expert driver and throttle man. He drives boats with a lot more power than this one has just about every day. He is also an expert tuner. I hope we get this all worked out without incident. If things seem to not come together with this hull I guess that I will move on and try something else. David seems pretty confident that it will come together great. He isn't thrilled on one hand about raising the center of gravity but he thinks the boat will handle getting "up on the pad" without quirks a lot better with the drive not so deep in the water. He also thinks that the dual ram full hydraulic steering, a 4x4 or #6 with a much deeper skeg and the extra 12 inches of set back will all help the stability.

Once we (he) gets all of that worked out..I will ease into my seat time. I have driven a lot of high HP vehicles from 1,100 hp mud racers to 8 second drag cars to motorcycles that will toy with the 200 mph mark. I have done pretty well so far. I am not the kind of person that goes farther that I feel is safe. I feel a lot better about strait line stuff that turning corners. That is not my thing and it seems that is where a lot of boaters get in trouble. With that being said. I have seen my brother prop testing a 95 mph bass boat that seemed pretty solid one minute and caught some air and was 20 feet in the air with the bow pointing straight up and the engine pointing straight down about 5 feet off the water. He came back down until the engine hit the water and it brought the boat back down right side up but it was hairy. I WILL take it slow when getting my seat time in. That is why I made the statements earlier about AOTH. If the boat is not ready or I am not ready I will not go past my comfort zone.

Now that I have all of that out of the way...What do you think about a 4x4 or the #6? I was thinking Arneson but I have talked to several people that had nightmares getting the right setup. I am talking 1000 hp and couldn't get on plane for days of testing.

Give me some more advice. I have been waiting for you and X and Lenny and all the rest to join in and help me out!!

[BUIZILLA]

I have no personal experience with the 4x4 or #6 to merit an opinion

[SilverBack]

What about the mufflers??

What does HTH mean?? I am slow!!

[BigGrizzly]

I have driven a lot of boats including ones with the #6 drive. However you are talking about a 25 Donzi with a 24 degree dead rize and a pad. When You get it up on the pad it is going to feel like its on a floor full of marbles. No amount of set back is going to cure that. I will tell you what will happen. It will be OK up to about 84mph than with any change of water, rouge wakes , wind or such it will start to wander- like chine walking. If you back out too fast it will really become unruly, it probably won't flip but you will have ti change under garments! The real problem is there is no warning with a pad. I know this because Python used that same hull for their 24 python that Garry bough. He put a 383 with a larde roots blower in it to the tune of 850 HP( on a bad day). He also has the setback and the IMCO on it. That drive is rated for 1000hp and so far here it hasn't given us any problems, even with Mister Throttle Jerk's boat. As for the Horse power on pump can be done.
Stang you are correct about my boat. I run 4.7 psi in the box. Remember this is different than 5 psi in the intake. My boat and driver only will go 86 mph cause that is enough- and I have all the goodies in the handling department, and I have been driving fast boats for a long time. I will have to agree with buz your putting a lot into a boat at first go round. To be perfectly honest with you I wouldn't put that HP in a 502 block. I would use a 540 or 572. We backed my engine down from 752Hp for that reason. I just don't want to fix any more. When I break it is big time no little stuff on my boat. Again good luck

[SilverBack]

MJW,
You are right about the prop. 5 or 6 blade is what David is saying. He says that those props hold the boat better and have less quirks. He is going to do some prop testing and then I will get up with Randy to see what we can come up with.

Randy thanks for the info!! That is the kind of information that I was looking for.

I emailed the tuner and he is going to get a smaller crank pulley and try to get me down to 2 psi right now. That should put me in the low to mid 700 range.
That is all this drive can handle anyway.

It sounds like that may be as fast as I need to go anyway from what you guys are saying.

[SilverBack]

It is kind of quiet on the project right now. Waiting on the IMCO....Risers, Extension box and steering. My wife went by the upholstery shop today and the man was out sick that is doing the work but she took a few pictures. I will post them here.

[BlownCrewCab]

I Didn't see any pics of the wife...WHAT???? All I saw was seats and combing.....J/K Man I bet your going stir crazy now you have to wait on parts, When are you going to get to see it again?

[SilverBack]

Hello guys..I have a question on steering. David ordered me a complete IMCO steering setup. HE also stated that he ordered me a high pressure pump. He said that the higher pressure pump added responsiveness to the setup.

Did you change your pump out? Do you have any experience with this?
Thanks!

[yeller]

I Didn't see any pics of the wife...WHAT???? All I saw was seats and combing.....
:rofl: Wife make ya delete the pic. :tongue:

[SilverBack]

Well......not exactly..I just thought that it may have been a little dorky to post a picture of my wife on a thread about my boat....no one gave me any advice today....HATERS....but I guess that I can see why you would think that!

[BlownCrewCab]

Are you talking about the power steering pump? On a single Drive I'd use a Char-lynn or the like, maybe even a adjustable rate pump and lose power steering. It'll turn almost as easy and you won't have a power steering pump and belt to worry about. If you absolutly have to drive with one finger then power steering is for you, I Like the feel of a self contained Hyd Helm pump. especially at speed when every little steering input is going to be a big input, the faster you go the more you'll feel it in the wheel, whereas with power steering it always feels the same.

[The Hedgehog]

Well......not exactly..I just thought that it may have been a little dorky to post a picture of my wife on a thread about my boat....no one gave me any advice today....HATERS....but I guess that I can see why you would think that!

I am using my factory pump. I think that most do that. Griz actually uses an electric assist pump. I think that is a pretty cool idea.

[SilverBack]

I am not sure!! I think we are getting rid of the power steering pump all together. I think it is a high pressure helm pump of some kind. He stated that it would make the steering more responsive and that on he likes to go this route on faster boats. I had never heard of throwing out the power steering! I was just wondering. It sounds kind of what you are talking about Michael. I thought that it was an electric pump that would still be running if the engine stopped?

[BlownCrewCab]

On the Old Hogs Breath Boat (26 Corsa) We added a Standoff box, And a N/A 502 and had no power steering of any kind, Just a Charr-Lynn Helm and Dual Rams. Boat ran over 90mph, Over 90 (even over 80) on a 24degree V is a hand full and takes good steering input to stay up right and that Char-lynn helm did perfect, no power anything.

[SilverBack]

I bet that was a very good system! I have read about people with full hydraulic dual ram steering flying across the water and the engine blows or something locks up and wham ..no steering either.

[BlownCrewCab]

I Can Attest to that, I Have done it!(Too Many Times) Flying across the water and throw a rod, and KKKKKKKKKkkkkkkkkkkkkkkkDDDDDDdddddGGGGGggggKDGkdg Is what it sounds like, and steering effort remains the same, cause it's not attached to the motor in any way. Your coming to an Abrupt stop so not a whole lot of steering is required, but you can turn if you wanted/Had too.

[SilverBack]

That is some really good information Michael!! That would give you a little more piece of mind I would think!! Thanks for the info!

[BlownCrewCab]

No problem Keith, I'm trying to be sure you get the "Best Bang" For your money, I'm not trying to sell you anything, and I just want you to know whats out there. You may not know whats a good system to use and other people may be trying to get you to get something so "They" can make a buck. I Don't know if thats the case, I Just hope not. But a simple system is less problems (and less cash)

[SilverBack]

Well....I just talked to David and ...that is not exactly what he was talking about. The thing that I got was a helm that only takes 2 turns lock to lock. He said that the regular one takes 3.5 turns lock to lock and this was just a little more like a race car steering and takes smaller input.

[mjw930]

Sounds like he's just spec'd a higher CC helm. Here's the turns chart from IMCO

2 RAMS WITH 1" DIAMETER RODS

STROKE STROKE STROKE STROKE
6 5/16" 8 1/4" 9 1/4" 10 1/4"
HELM TURNS
75CC 3.60 5.20 6.00 6.80
95CC 2.84 4.10 4.73 5.36
120CC 2.25 3.25 3.75 4.25
145CC 1.86 2.68 3.10 3.51
160CC 1.68 2.43 2.81 3.18
185CC 1.45 2.10 2.43 2.75
230CC 1.17 1.69 1.95 2.21
295CC .91 1.32 1.52 1.72

Example, 8 1/4" stroke with a 185CC helm = 2.10 turns lock to lock

[SilverBack]

MJW,
Thanks!! I didn't know what he was talking about until tonight. Do you like the faster responding ones or what?

[mjw930]

2 turns lock to lock is perfect IMHO.

It's slow enough to be able to control the boat with mild inputs on the pad at speed but fast enough so large inputs don't have you sawing at the wheel.

It also makes it easier around the docks and since the blower motors are notorious for being finicky at idle every little bit helps.

[SilverBack]

Thanks..MJW,
Sweet! This thing is getting really close to coming together. It had slowed down a little in the last week or so but now that the extension box and steering and drive have come in and the engine is ALMOST ready to go again it is starting to move a little faster. My interior is waiting on these crazy embroidery people to get their act together but other than that we are getting closer.


I know what you mean about the docking!! I am dreading that learning curve. I hope the paint makes it through ok. It is like you said ..I have heard that it is hard to dock with a blower motor and I know it seems harder for me with a higher pitch prop (like 32-34)

I hope this thing is going to handle like David thinks it will!!

Oh yes, I need to hear from MJW, BLOWN, BGZX and LRT on this...Do you think that it is worth the money for me to have the hull Blue printed????


What about trim tabs. I keep hearing Bill and Bryan talking about huge tabs..David thinks the ones I have will be just fine. What gives??

[The Hedgehog]

Thanks..MJW,
Sweet! This thing is getting really close to coming together. It had slowed down a little in the last week or so but now that the extension box and steering and drive have come in and the engine is ALMOST ready to go again it is starting to move a little faster. My interior is waiting on these crazy embroidery people to get their act together but other than that we are getting closer.
I know what you mean about the docking!! I am dreading that learning curve. I hope the paint makes it through ok. It is like you said ..I have heard that it is hard to dock with a blower motor and I know it seems harder for me with a higher pitch prop (like 32-34)
I hope this thing is going to handle like David thinks it will!!
Oh yes, I need to hear from MJW, BLOWN, BGZX and LRT on this...Do you think that it is worth the money for me to have the hull Blue printed????
What about trim tabs. I keep hearing Bill and Bryan talking about huge tabs..David thinks the ones I have will be just fine. What gives??
Sometimes you need big tabs and sometimes you don't. Tex needs no tab input at all at 85, I am talking to a guy with a big power 26ZX that is going to 30" tabs to keep his from walking around above 80.

If your hull is straight and true then don't worry about the Blueprint. You can figure that out somewhat with a straight edge. If you have some warpage, it might be a good investment.

My hull seems pretty straight so I am going to wait till I start testing to worry about tabs and a possible blueprint. I am prepared to do either if necessary.

[mjw930]

I agree with BG, throw a straight edge on the bottom and see how it looks.

Considering this is basically a new boat, performance wise, I would throw a straight edge on it and see where it is today. Note whether it has any hook or rocker then see how it performs. You may find you need some hook to settle it OR you may want to take existing hook out if the boat doesn't sit up on the pad like it should. It sounds like your guy knows fast hulls so let him help you dial it in and go with his advice.

[BigGrizzly]

Your not going to turn a 34 pitch prop. I doubt you will turn a 32, even with a super shorty. I guess its time to be blunt. Your boat is big, pad or no pad. the frontal area is large. I have 690+ HP and a deep drive I turn a 28 and 29 prop Catch has a shorty and turns a labbed 30, which is a good 29 and we are lighter and smaller boats with smaller frontal areas. I was talking to the Dyno king yesterday about your project. He says once your over 750HP with the 502 block engine life shortens dramatically. I am not at liberty to disclose who's engines they build, but they do know blower motors better than most. It seems to me like your moving hard and fast, slow down a bit. At this point you have a beautiful boat, a classic in every sense of the word, lets keep it that way. As for changing to a cat later, that is another breed, turning ride etc(not going for what is better here and I will not get into that!). I want to see this project done and done right. As for the steering I understand what he is doing, but don't totally agree. At low speeds it will be a pain. I have power steering but Have slowed mine down by using a smaller orifice in the power pump for high speed and sacrifice very little at low speed. My little boat has an electric power assist unit that is switchable, on and off which is great. I don't really care what you have driven before, this is a new ball game. I have raced cars boats and motorcycles for 40 years and each is different my AFX hemie was way different than the AA fuely. and worked with Jungle Jim, than any boat or my formula I road racing motorcycle are all different beasts! Don't get caught up in the glory trail, I like having you on the board. If I am sounding like a parent it is because I have come very close to the other side and have been very lucky. None of my health issues are racing related, because I was careful and lucky. NOW I will get off my soap box. If I can help feel free to call home 706-216-8194 most times or cell from 9:00am to 6:00pm, some times later. Now we want more pictures!!!

[Last Real Texan]

Your not going to turn a 34 pitch prop. I doubt you will turn a 32, even with a super shorty. I guess its time to be blunt. Your boat is big, pad or no pad. the frontal area is large. I have 690+ HP and a deep drive I turn a 28 and 29 prop Catch has a shorty and turns a labbed 30, which is a good 29 and we are lighter and smaller boats with smaller frontal areas. I was talking to the Dyno king yesterday about your project. He says once your over 750HP with the 502 block engine life shortens dramatically. I am not at liberty to disclose who's engines they build, but they do know blower motors better than most. It seems to me like your moving hard and fast, slow down a bit. At this point you have a beautiful boat, a classic in every sense of the word, lets keep it that way. As for changing to a cat later, that is another breed, turning ride etc(not going for what is better here and I will not get into that!). I want to see this project done and done right. As for the steering I understand what he is doing, but don't totally agree. At low speeds it will be a pain. I have power steering but Have slowed mine down by using a smaller orifice in the power pump for high speed and sacrifice very little at low speed. My little boat has an electric power assist unit that is switchable, on and off which is great. I don't really care what you have driven before, this is a new ball game. I have raced cars boats and motorcycles for 40 years and each is different my AFX hemie was way different than the AA fuely. and worked with Jungle Jim, than any boat or my formula I road racing motorcycle are all different beasts! Don't get caught up in the glory trail, I like having you on the board. If I am sounding like a parent it is because I have come very close to the other side and have been very lucky. None of my health issues are racing related, because I was careful and lucky. NOW I will get off my soap box. If I can help feel free to call home 706-216-8194 most times or cell from 9:00am to 6:00pm, some times later. Now we want more pictures!!!
words to LIVE by..............

[Last Real Texan]

Thanks..MJW,
Sweet! This thing is getting really close to coming together. It had slowed down a little in the last week or so but now that the extension box and steering and drive have come in and the engine is ALMOST ready to go again it is starting to move a little faster. My interior is waiting on these crazy embroidery people to get their act together but other than that we are getting closer.


I know what you mean about the docking!! I am dreading that learning curve. I hope the paint makes it through ok. It is like you said ..I have heard that it is hard to dock with a blower motor and I know it seems harder for me with a higher pitch prop (like 32-34)

I hope this thing is going to handle like David thinks it will!!

Oh yes, I need to hear from MJW, BLOWN, BGZX and LRT on this...Do you think that it is worth the money for me to have the hull Blue printed????


What about trim tabs. I keep hearing Bill and Bryan talking about huge tabs..David thinks the ones I have will be just fine. What gives??
leave the bottom alone until you get some time in the boat and see what it needs before changing the surface...no reason to do it twice, it may be fine and it may need some work...On the steering thing, I have a helm that gives me 3 turns lock to lock....perfect for me but maybe not for everyone, I have never driven one with 2 turns lock to lock so I cant say how it performs. Keep up the good work, Grizz is right it is nice having some fresh ideas on the board with execution instead of BS .....Great job and post more pictures!

Tex

[BigGrizzly]

Follow the Texan, some hooks you don't want to remove, it can become too loose. the old thing applies here "Try before you buy". I have made mods in the past I had wish I had not done. You need to know where you are first before you know where your going.

[The Hedgehog]

Follow the Texan, some hooks you don't want to remove, it can become too loose. the old thing applies here "Try before you buy". I have made mods in the past I had wish I had not done. You need to know where you are first before you know where your going.

"You need to know where you are first before you know where you are going" That is one of the best quotes I have heard in a while. So true.

I am facing some of that as my project is coming together. I have had a number of interesting conversations with some others that are or have taken 26ZX's into the high 80's and low 90's. I find myself wanting to implement some of their solutions before mine even hits the water. I have to remind myself that mine is setup slightly different than theirs so what works for them might not work for me. There is nothing wrong with preparing yourself for potential problem but you have to know what it if first.

Will I need bigger tabs? Probably but dunno and dunno how big.

Will I be able to stick on a 32" bravo and be done with it or will I be driving down to Atlanta hoping that Griz has some time to prop it right in hopes I can keep it under control? I dunno but time will tell.

[BigGrizzly]

I am here. You don't really think it will be that easy to put on a 32 Bravo do you? Remember I know you, almost good isn't good enough for you or the Texan!

[The Hedgehog]

I am here. You don't really think it will be that easy to put on a 32 Bravo do you? Remember I know you, almost good isn't good enough for you or the Texan!

I appreciate that. And no, almost good is not enough. Especially this time. I already learned one lesson by spending a bunch of time mailing props and getting it done almost good. This time I will spare that headache and just come see you instead. Thanks

Bill

[SilverBack]

Thanks guys!! I really appreciate all of the advice. I am getting really hyped up about this project and it kind of got me excited when I actually spent the money and pulled the trigger and made the decision to go with the box and the dual ram steering. I know that I am going too fast but I will be careful. Like I said before on this thread...I am a consultant and believe in hiring an expert and letting them do their thing. I was asking the blue print thing just in case it comes up in the future. If it needs it I will have it done. I want the boat as manageable as possible without as many quirks as I can do away with. It sounds like there are a lot of things that a good hull and glass guy can do with a hull. As for the 502 and the HP. The procharger and injectors are all back off and back on in a little different configuration. I am detuning the engine a little and while the 85# injectors work good at the HP that we were at before they might not be the ticket at 700 hp. I think that is where this engine is headed. We are actually waiting until we can mock up the engine and box and get all of that squared away to order the exact right risers. I know that I will not be pulling a 32-34 prop right now. My brother has pulled the trigger on the 698 CI aluminum Dart short block with titanium rods and the works. He is getting a set of Dart heads that he has dressed out with the Jesel shaft rockers and the whole nine yards for a marine M-5 application. I keep telling him that this hull can't handle something like that but we could find him a skater hull or something.

You are all in luck..I drove in from the rig today and I am going to Baton Rouge to meet with David tomorrow. My wife is going and I will get her to take a few pictures so they should be up tomorrow night. The drive is in so I will get a picture of that too. The box and steering are not on so don't expect too much. Grizz. I am glad you said what you said and it is good to have a grownup giving fatherly advice. Thanks again to everyone for helping me out!! It is very much appreciated!!

[BigGrizzly]

Like I said I like having you around. The excitement your showing is really nice and contagious too. This is what the Donzi mystique is all about. If the wife is going an she is giving the approval it seems like time to take her out to a really good dinner, just because it is Saturday.

[SilverBack]

Grizz,
I did just that last night!! She is great! I started to say something when someone said something about hiding the checkbook before. She is a pretty good ole girl. We have been married for 17 years and she doesn't give me too much trouble about things. Most of the time she is the one writing the checks for me when I need parts or if I am out of town. I just hate that I am not going to be able to keep it quiet for her like she had wanted.

We went to Baton Rouge but there wasn't much to take pictures of yet. Page, my wife, took a few but the engine has been torn partially back down and is waiting on a few things to put it back together again. The last dyno run was not using my exhaust manifolds. There is a slight clearance problem with the procharger and the manifold. David used some headers that he has on that run before but he wants to put it together with everything the way it is going to be in the boat for the next run. He said he was just getting some ideas about what he was looking at before. That is why he didn't send me the run sheet. He is going to have to do some modifications and change a pulley out and he has to get the injectors back from the injector shop and we will be back on the dyno this week. Needless to say I don't think we will be anywhere close to the 890 HP range again. More like 700 to 750 in the detuned state. He hasn't taken the fuel pump off of the seawater pump and he has some more finishing work to do and a few brackets to get done and he has to pretty everything up but it is coming together.

The drive doesn't have the right gears so I think that I am going to be in for a new upper like LRT's. I will post a few pictures but they are not very good in the next couple of post. Tell me what you guys think so far!

[SilverBack]

The drive is not much to look at but here are a few shots of it and a few other things.

[SilverBack]

A few more pictures.

[The Hedgehog]

Looking nice Keith.

I really like the carb hat and chiller setup. That should have some very clean air flow.

I see that you are learning about detuning. Some engines once setup are happier at bigger power and you can't simply just turn down the boost.

You have learned a bunch in a short period of time.

I am still scratching my head about why you don't seem to like my diving board idea.

[SilverBack]

LMAO, Bill....I was messing with David yesterday about the swim platform extension and he even wouldn't go for it. He said this thing is a Donzi..you are not going to screw it up like that. I guess that great idea never really got off the ground.

[BigGrizzly]

I am beginning to like David more and more-loose the platform idea!!! No offense but your boat pictures are more inportant to me then some stinkin skater's pictures.

[SilverBack]

Grizz,
The platform is gone and Bill,.....I hate to say it but the diving board is too!! Hey Grizz..you are not a Skater hater are you???

[BigGrizzly]

I don't hate anything that is fast and reliable. They build a good boat.

[SilverBack]

I was just kidding Randy. I didn't think that you really hated Skater.

[SilverBack]

How do you guys like that Cigarette?? The guy only had it for 3 days when that happened. Luckily everybody was thrown from the boat before it ran into the woods going 65-70 MPH. High speed cornering.....Not wearing a lanyard...I am glad that everyone made it!!

[mjw930]

How do you guys like that Cigarette?? The guy only had it for 3 days when that happened. Luckily everybody was thrown from the boat before it ran into the woods going 65-70 MPH. High speed cornering.....Not wearing a lanyard...I am glad that everyone made it!!

I was going to ask what happened there. That's usually what happens when they slap 2 ventilation steps on a hull that was designed as a straight 24 degree deep V. The boat goes real fast in a straight line and can't negotiate turns without a whole lot of seat time and even then it's a crap shoot. Cigarette is living on their legend, I don't understand the love affair everyone has with them these days.

[BigGrizzly]

Lets not hijack this thread, but I do agree. Funny the Cigarette people say the same about Donzi. When in that discussion I say its the Donzi mystique. The then look at me like the RCA dog looking at the speaker. I then say "You wouldn't understand". Truth is I don't own a Cigarette shirt or any thing. BTW stang I knew you were funning, the Skater statement was for the sensitive types.

[mjw930]

Lets not hijack this thread, but I do agree. Funny the Cigarette people say the same about Donzi. When in that discussion I say its the Donzi mystique. The then look at me like the RCA dog looking at the speaker. I then say "You wouldn't understand". Truth is I don't own a Cigarette shirt or any thing. BTW stang I knew you were funning, the Skater statement was for the sensitive types.

Point taken on going off topic but I'll add this one last comment.

When asked about "living on your past reputation", I would simply point to:

2002 APBA F2 National Champions
2003 APBA F2 and Super Vee National Champions
2004 APBA F2 National Champions
2004 APBA / UIM Super Vee World Champions
2006 UIM P1 World Champions

[SilverBack]

Does anyone have any information on forged XZ gears vs XR gears? Pressed in steel towers vs threaded??? I talked to IMCO today and my drive has a pressed in steel tower and forged XZ gears. They said that this drive should hold up to the HP. What do you guys think??

[SilverBack]

I need to clarify my last comments. I was talking about the upper drive. The lower has the big shaft and the XR gears.

[SilverBack]

The engine went back on the Dyno stand today!! I guess we will know something about the finished product soon!!

[The Hedgehog]

Would you hurry up and get us some numbers?

[SilverBack]

I am waiting to see some numbers in the 540 fun and winter project threads first!!

[BigGrizzly]

Now guys be nice, just got done dynoing a 540 with a 871 blower and super chiller at 867Hp at 5,700 with 890lbs of torque. we don't want the owner to run it that high for too long. It was a fun day especially since there were not any large unforeseen issues. I don't know what it is going in but it is a single application. I don't want to see the bill on this, Only the best of the best went in that engine! From modifying the heads, to the rod bolts, even the oil pan screws were the best available.

[SilverBack]

Big Grizz,
What kind of props do you have in mind to start out looking at for my setup?

[BigGrizzly]

You are in uncharted water. Firs we need to know the hp and torque then the gear ratio of the lower unit. From we need to know how high the X really is. Then we do an educated guess and do a test. depending on everything we use the least amount of blades we can get away with safely without sacrificing stability. Remember don't bring a tractor trailer if everything will fit in a van! Of coarse we can hook up and I bring an arsenal. Btw here is that 572cid.

[The Hedgehog]

Wow Griz,

That is a beast!

[SilverBack]

OK Grizz....We left the hole in the transom in the stock location. I am running a -2 IMCO lower and the extension box is a 3 inch raised box. The prop shaft now measures 4 inches below the pad. The HP is going to be between 800 and 850 from 4500 all the way to 5700. The torque is between 850 and 950 all the way from 2500 to 5250. I can email you a dyno run sheet next week on the final product if that will help but those are the ranges we are going to be in.

It is killing me to give too much data away!!:doh:

Bill and Bryan will not even talk to me any more!! They are planning to gang up on me at AOTH!!

[Last Real Texan]

OK Grizz....We left the hole in the transom in the stock location. I am running a -2 IMCO lower and the extension box is a 3 inch raised box. The prop shaft now measures 4 inches below the pad. The HP is going to be between 800 and 850 from 4500 all the way to 5700. The torque is between 850 and 950 all the way from 2500 to 5250. I can email you a dyno run sheet next week on the final product if that will help but those are the ranges we are going to be in.

It is killing me to give too much data away!!:doh:

Bill and Bryan will not even talk to me any more!! They are planning to gang up on me at AOTH!!
Nah......Been busy working out of town, and getting ready for long month of it as well, Going to try and get things finished up by friday and then I am gone out of town from March 19-April 8....argggggghhhhhhh.

Bryan

[BigGrizzly]

What is the drive ratio? I really don't want to put a 32 on it, because acceleration will be a bear as will keeping it planing at low speed. I still think your pushing the ponies on a 502 base. The torque is impressive on that small a motor. What blower did you put on it, because the torque figures seem more like a roots blower statistics. and the boost seems it would be above 5 PSI. The last time I saw these similar numbers it was on a 540 with a roots blower in a 22 classic that actually ran 104MPH. the guy changed his underwear and pulled the motor and sold it. How ever it could be a fun project, I may have to come down or you come up and burn up your fuel from the co pilot's seat. Who knows maybe I can give you a pointer that you don't already know. However you will have to feed me too!
This is the longest thread we have had that somebody didn't get PO ed about, I like this!!!

[SilverBack]

Grizz,
The CNC ported AFR heads and the Super chiller with the common rail injection seems to make a good bit of difference. I was surprised how quick that torque gets up there. I know you have to run a bigger size pulley to get the desired boost. To get 5 psi we had to run the 7 psi pulley and to get 3 psi we had to run the 5 psi pulley. The crank scraper and windage tray and all of the other little things must be doing their jobs too. The cam really puts up monster torque numbers. My engine builder says that he has a rule of thumb of 1 psi = 32 CI. I don't know just something that he said.

My drive ratio is 1.36:1 I have the 1 1/4 prop shaft.

My hull seems a little thinner than any Donzi that I have seen. I know that is not a very specific thing but this boat is much lighter even with the BBC than my 23' Ragazza was with SBC.

Was that classic a 22? Did it have some handling quirks?

[BigGrizzly]

That is a good start for propping. I was pretty sure you had the XR output shaft. The 1:36 is where I would have started with that motor. I am afraid this will be a hand full, but time will tell. The good thing is you don't have to use all the power but can if you want.

[SilverBack]

Grizz,
Do you have any idea on a starting point on props? Maybe we can get together in April. I am sure that you can give me some good pointers!

[BigGrizzly]

We need to try the 4bllade 30 fusion than 5h3 the 5 blade 30 just to get a handle. Like I said this is uncharted waters especially with a 25 pad bottom. Now Gaqrry's 24 pad bottom python with his 383 with the 1471 blower and a -3 inch shorty runs one of my 26 or 28 depending if acceleration or top speed is needed. He does not have an extension box but does run 115 mph on a good day with a jock strap in his trousers. He can turn over 6000 if need be but never does, something about littering the waterways .

[SilverBack]

My rev limiter has to be set with the computer so I guess that 6,000 would be good. What do you think? My peak HP is pretty flat from 5,000 to 5,500 and it drops off 20 HP from 5,500 to 6,000. The torque drops over 80 foot pounds in the same range. What kind or slip do you think we will see with the 5 blade prop?

[BigGrizzly]

As soon as you raise the X the slip goes up because of the amount of prop in the water. I am not going to get trapped in to the slip discussion, there is no way to tell until it is doing it. My rev limiter is set at 6,000, but I don't ever take it above 5,200 unless by accident.

[SilverBack]

Who makes the Fusion and 5H3 props?

[BigGrizzly]

They are produced by Turbo. I have been working with on the 5 blades for several years, at this point I can always beat the Maximus both in handling and speed. As for the fusion it was developed for high X dimension boats but have had some good and bad luck on std X hulls. I don't lab finish things because it isn't worth the 1 mph for the dollars spent. Now the Fusion, The TXP, and the 5 blades are what is called blueprinted- not labbed.

[SilverBack]

Sounds good Grizz. I found the Fusion on the website but didn't see the 5 blade. What kind of money do they run? I might need a couple of different pitches. Can you tell me a little more on the comparison between the Maximus and the Turbo 5 blade. What is the diameter on the 5 blade? Is Turbo the only 5 blade that you sell? Do you have any 6 blades? I don't think that I am going to need one but David likes these 6 blade Herring props and he also likes the Maximus. He doesn't like Hydromotive at all!!

[The Hedgehog]

I am in Griz's camp on the blueprinted vs labbed. I guess that labbed might work on some light cats but on heavier traditional v's I have found now real benefit except for slightly better top end. That comes at the expense of a slower cruise and weaker blades.

Tex and I have both discovered a 3 mph loss (maybe more) on cruise and nominal top end benefit on big single ZX's. With the kind of HP your boat is slinging it is not worth paying for labbed and may actually be worse.

I have spent days pulling props on and off while talking to the "experts" that bang on props. I will be going down to Lanier this spring when the time comes.

[SilverBack]

Bill,
You ARE alive!! Good to hear from you man! I agree with you totally!! I was hoping to get out of this without getting a labbed prop. It is good to hear that Grizz agrees. I don't think that I will be looking for the LAST MPH any time soon anyway!! I probably will not really be looking for the last 4 or 5 MPH!! J/K With all of the variables and all the stuff that has changed on this setup since the last time it was in the water there is no telling what I will be looking at or how long it will take me to really get where I will be able to handle it! Right now I am back to my original goal of being able to cruise in the 60 - 70 MPH range without too much drama!

Are you back in TN yet? Like I said..it is good to hear form you! BTW..which boat are you taking to AOTH?? It sounds like they really want the X-18 guys to bring their X-18's??

[BigGrizzly]

Don't get me totally wrong, but labbed props do work for top end and some acceleration problems. The real problem for me is you can onlu do it once to a prop safely, and make no mistake they DO break with big power. We get about 16 hours max on a labbed prop with over 700 HP that is run fairly hard. When you raise your drive it adds insult to injury. No matter what they say it is almost impossible to make two props exactly the same. especially if the original is broken. I don't know about you but instead of having a labbed prop that adds 2 mph, I would rather have two props of different attributes ie a loaded boat(easier on the lower unit) and one for top speed when Big Green or the Last T is around:wink: As for 6 blades I don' normally stock them, only one out of a hundred can benefit from it. There is a point of decreasing returns and it doesn't pay off. Besides If I was able to get Fast Cash to plane at 20 mph with 5 blades what is the point. He was happy I saved him $8,000 on Herrings. As for price Mine are about same price as Hydromotives and maybe less depending if we need to design a special one for you. We need to prop and play. I am Italian, but I am not stupid enough to tell you I can prop it on the first shot! Let some one else fling that BS.

[SilverBack]

That sounds great Randy!!! I am with you on the labbed thing. I don't want to be slinging blades and I am not going to be racing anybody!! What diameters does your 5 blade come in? I am sure that I will not need a 6 blade. I was just wondering because David was talking about trying a 6 blade Herring. I am going to buy 1 prop from him I am sure. He will be doing setup and testing and I am sure that he will come up with something that will be right for the boat. I am looking for this to be a Maximus or Herring. Then when I get the boat back you and I can take it from there. Like you say. I am going to need a high pitch for faster cruise speeds and a lower pitch to run most of the time that is easier on the drive and better with 5 people and full of fuel and a bunch of gear in the boat. Maybe we can get together once before AOTH and if we need to come up with something that you don't have on hand that will give us a little time before AOTH. Thanks!!

[The Hedgehog]

Bill,
You ARE alive!! Good to hear from you man! I agree with you totally!! I was hoping to get out of this without getting a labbed prop. It is good to hear that Grizz agrees. I don't think that I will be looking for the LAST MPH any time soon anyway!! I probably will not really be looking for the last 4 or 5 MPH!! J/K With all of the variables and all the stuff that has changed on this setup since the last time it was in the water there is no telling what I will be looking at or how long it will take me to really get where I will be able to handle it! Right now I am back to my original goal of being able to cruise in the 60 - 70 MPH range without too much drama!

Are you back in TN yet? Like I said..it is good to hear form you! BTW..which boat are you taking to AOTH?? It sounds like they really want the X-18 guys to bring their X-18's??


I am alive but have been pretty busy. Keep up the good work.

[BigGrizzly]

502, I would go with the maximus if your going with your builder first. Simply because for the price verses the performance and availability. With the shorty you can't swing anything bigger than a real 15 1/4 diameter, been there on this one, even then you start hitting the attaching bolt on the spray plate. You are correct on the prop for the occasion. I don't even take my top speed prop along, mainly because I always run full fuel and usually 4 people, so handling and economy are my first top priority at the events. After 80 mph the fun goes away and work starts. Like my son told me, " if you really wanted to win that bad you could". You see I always stay in my element. There is always someone faster and smarter. I'm not racing speed racer or a cat with 2,000 hp so it just doesn't matter.

[BUIZILLA]

call me whatever you want, but your builder is starting to confuse me... :confused:

[RedDog]

502 Stang - its amazing how far you have come from the Medallion jet and the Regazzi on such a fast pace! Looking forward to seeing the monster 27

[SilverBack]

Red Dog,
Thanks for the kind comments!! I look forward to seeing all of you guys there at AOTH also! Everyone keeps telling me that I am moving kind of fast but it seems like things have really slowed a lot to me. I hope that the 25 ZX is not too much of a monster although there will be a 26 ZX and 27 ZX monster at AOTH. They are both close to you as a matter of fact!

I hope to see you there!!

Buiz,
What are you confused about now???? :propeller:

[SilverBack]

I guess that it was just a rumor that you were going to do a pose down when you unvailed the 25ZX for the first time!

Hmmm. My boat, I am trying to figure that one out as well. Still waiting on it to go to the dyno. He had to do some custom fab work on my rails because I did not have that cool Gorilla setup. My engine builder is a small shop and ususally does a few at once. I am thinking it should go soon as I hold the final check:wink:

BG,
I didn't want to :hijack: the other thread. This dyno crap is killing me! I have never ever had an engine on and off the dyno for 2 weeks. This COOL Gorillia setup is costing me a fortune and driving me crazy!! Really the computer and injectors...all of this stuff is "not a normal setup"!!! It is really starting to confuse me and Buiz!! If it is putting up good numbers and all of the cylinders are looking good...that should do it..right?? When I talked to David yesterday he said the drive and box and steering will all be set up this week and he thinks there is a good chance the engine will be in also. Maybe I can get some pictures Friday. Although Friday is the day when all of the "Big Money" guys want their Fountains and Cigs and Skaters and Eliminators to play with on the weekend.


I have kind of turned my attention to props right now. Have you run any of the Turbo props? What did you think?

[The Hedgehog]

BG,
I didn't want to :hijack: the other thread. This dyno crap is killing me! I have never ever had an engine on and off the dyno for 2 weeks. This COOL Gorillia setup is costing me a fortune and driving me crazy!! Really the computer and injectors...all of this stuff is "not a normal setup"!!! It is really starting to confuse me and Buiz!! If it is putting up good numbers and all of the cylinders are looking good...that should do it..right?? When I talked to David yesterday he said the drive and box and steering will all be set up this week and he thinks there is a good chance the engine will be in also. Maybe I can get some pictures Friday. Although Friday is the day when all of the "Big Money" guys want their Fountains and Cigs and Skaters and Eliminators to play with on the weekend.


I have kind of turned my attention to props right now. Have you run any of the Turbo props? What did you think?

Props is a trial and error. It is a good process but must be done. I will probably put a Turbo on my X-18 but I am waiting to try it. It is supposed to be a little more stable vs the Mirage Plus

[SilverBack]

UPDATE:
I talked to the guys at DW marine today and they have the steering, wing plates and extension box mounted. They got the wrong hoses so they are haveing to send the rubber ones back and get the stainless braided hoses.

They painted the bildge with a really cool 80's looking paint scheme with red splatter paint. They are getting some diamond plate cut to go in the bildge as well. I think they will have that in tomorrow and maybe get the billet optima hold downs mounted.

Shouldn't be long now!!

[The Hedgehog]

Keith,

It was good to talk to you the other night. I like a man that steps to the plate. You are not messing around. That will be the hottest and fastest 25ZX. By FAR!

[BlownCrewCab]

Lets just hope Keith has enough cash left over to put Gas in that Bad boy...

[SilverBack]

Bill,
Thanks for the kind words! You have been a great help to me on this project!

Michael,
You are a very wise and insightful person!! I am worried about the same thing!! Thanks you as well! You and Justin have been a great help as well!! You really know your stuff!!

[The Hedgehog]

Keith, I copied this post from OSO. There is a guy that has a 25 Baja with a notched pad hull. His base speed was 81 mph. He is running an extension box and his prop high with the shaft about 2-1/2" under the pad. It looks like you will have your prop lower at 4" below the pad. I know that we don't know how your boat will respond but I thought that I would share the experience of someone with a similar setup:



"I ran my newest mod the other day. Adding to the 3" lift of the extension box, I swapped the standard length XR for a Imco 2" shorty lower. This brought the propeller shaft up to only 2 1/2" under the pad. I was hoping that by reducing the amount of drive in the water, I might find yet another mile.

But no! not a chance.

I tried three labbed Bravos - 28", 29" and 30" - and a labbed 26" Maximus.

On the first run with my old favorite 28" prop, I was encouraged by the fact that the boat came up only slightly slower on plane, with no slip or cavitation. The 525 actually doesn´t have much torque low down, so the additioinal grip that the noseconed shorty shape brings keeps everything hooked up, anyway.
Mid range was a little slower already, and I felt that the boat wouldn´t trim up and air out.
I was all over the revlimiter at 3/4 throttle, with 71 mph on the GPS.
I turned back to the dock thinking that the higer pitch was going to do it.

The 29" was no great help, and the 30" was even worse. The motor could hardly creep up from 1500 rpm, until we levelled off. Less revlimiter but no more speed.

The Maximus was better, and brought us up to 74 mph at just under the 5350 rpm. Still couldn´t trim the bow up. Essential for speed on a non-stepped Baja hull. The boat felt dull and boring to drive and was way below the speed I´m used to.

Time to go home. You can´t win them all, right?
I had a 1" spacer with me but the the day was turning cold.

When we get another warm weekend day, I´ll be back on the water with 3 1/2" prop to pad, and refreshed optimism."

[SilverBack]

Bill,
Thanks for the information!! That is good stuff! You are right!! I will be 4 inches below the pad with the prop shaft! It sounds like he has some huge slip going on! I don't know what gear ratio he has but it doesn't sound good. I hope that I will be far enough down to get hooked up. Grizz said that the higher you go the slip is kind of hard to guess about.

[BigGrizzly]

Plain fact the higher ht goes the less trim he will have. I will bet with that hull, he will be at leas with a 2 inch spacer. seems like he is going from a boat that was fine-81 with a 525 is actually really good on that boat. Personally I would have propped the hell out of it first. If he went with the box than the 2 inch spacer first then he would have know which way to go first. the bravos aren't going to give him what he needs for that application. They don't work well when elevated. I have a better option sitting on the shelf right now. Probably in a 29 pitch.

[SilverBack]

I read some more of the post over on OSO. This guy has a 1.50 gear ratio. There is another guy with a roots blower on the same hull that is going 96 MPH. The guy that the post was about has 24 inch tabs and loves to run his boat trimmed way up. The guy going 96 says that his tabs are not even in the water at those speeds. They are also saying that BAJA put hook in the last foot of the chines to help get the lower powered stock versions on plane better. I would think that may keep the boat from carrying the bow very well.

[BigGrizzly]

Actually that hook was on Donzis from the beginning and has no affect on the boat running at full tilt. in many instances it helps to raise the stern without dropping the bow. the hook is on the lifting strake on the far outboard sides. ?You don't want to take therm off, don't ask me how I know, one of my bad ideas, way back when. Not a good day on the Jersey Shore.

[SilverBack]

I got my new Life Line vest in today. Well..My wife did..I am back out in the Gulf of Mexico. She sent me a few pictures and I will post them. She also said the interior guy is about done.

This boat is needless to say NOT going to be a family boat anymore!! It is going to be a BIG toy to say the least!! I have the 23' Chris Craft deck boat but really am kind of a little upset that I have gone so overboard with this project. I really wanted to be boating in my Donzi not the Chris Craft!!


I guess since the notion of a family boat is out of the window I am going to just go full tilt with it. I know that I can't get my money out of this thing so new goals are in order. I thought about getting a 22 classic and putting all of the performance stuff in the 22 and putting the stock power and drive in the 25 for a FAMILY boat. But then I thought maybe I should just change up my thinking a little and have some fun with it. The family outings will be in the CC. I think my new goal is to make the 25 as NASTY and FAST as possible. I am thinking about hitting 100 MPH as my first goal. See how that goes and if all is well I will take my brother up on the 698 ci all aluminum RAT. Go with an M-4 and an Arneson drive next year. Do you guys think that would be safe?? I think we could squeeze 1000 to 1100 HP out the 698 ci with the Dart Pontiac heads on pump gas. Maybe more. I know that the Arneson can take it. Do you think 125 - 130 MPH is possible in this hull and still be safe?

Well...I guess I am going to have to be happy trying to get to 100 MPH this year with the 502.

They have got the bilge painted with some custom paint and diamond plate all around and bling all over. It should be pretty good looking .... I hope anyway!!

Do you think I should loose the IMCO manifolds and go with some thumping headers? Give me some good ideas..This thing is going to have to be sick now..Really sick!! I am going to try and track down the Gorilla top hat and plenum to run 2 of those 1000 CFM throttle bodies so if anyone sees or hears of one of those setups let me know!!

[yeller]

Well I think you just wasted your money on those lifelines.





You're going to need the full race jacket now...w/parachute. :biggrin:


BTW: Those jackets look great in the silver. :yes:

[mjw930]

Personally, I don't think that boat has the aerodynamics or hydrodynamics for the kinds of speeds you are talking about. I really think you're going to find that bottom to not be a whole lot of fun past 90 mph.

I have no idea what kinds of waters you boat in but unless they are relatively smooth you are going to find that all that top speed is unusable in a 25' boat on anything more than 3' seas. Some might argue and point to 18's and 22's that have "run with the big boys" but in general a 25' boat is a toy when the seas kick up. Oh, and is the 25' measured to the end of the swim platform? If it is then it's really a 23' boat.

I would also be concerned about hull strength. You are talking about speeds that are so far beyond the design criteria for that hull that it's uncharted territory. Everyone talks about how strong Donzi's are built but that's relative to other pleasure boats. I've seen too many purpose built race boats break at speeds well under what you're talking about to have any desire to try to reach 100 mph in a pleasure boat.

I don't mean to throw cold water on this but I think you are throwing good money after bad. These dollars would be far better spent on a hull that has a proven history at these speeds (and about 10' more running surface).

[BUIZILLA]

IMO, you might want to s.l.o.w. up a tad and re-think a couple things.. :shark:

[BigGrizzly]

930 we can push a brick over 100mph with enough horse power. In 1976 at OP sail in New York, outside the harbor. I tried to catch the carrier USS Enterprise with my 50= MPH 16 Donzi and she pulled away in a hurry. Now Stang You need to back off a little. You can still use it as a family boat- there is no law that says you have to drive full bore! Now if your mech can't make it have manners at slow speeds GET ANOTHER one because he isn't worth beans. As Garry Grimes would say" if you can't drive it you can't race it. You had the purse strings so you let it get out of hand. I really think you don't drive that 25 foot pad at over 100!!! Been there and I was just lucky. As I said before the kind of ponies your putting in that block is not a good idea. AT 750hp that block becomes fragile. Not trying to be dad but life is too short The vest is nice but not bullet proof. You still have time to back off. It is easy to detune with a minimum of $ and time.

[mjw930]

930 we can push a brick over 100mph with enough horse power. In 1976 at OP sail in New York, outside the harbor. I tried to catch the carrier USS Enterprise with my 50= MPH 16 Donzi and she pulled away in a hurry.

I agree but would you want to be riding that brick @ 100 mph :cool:

[The Hedgehog]

930 we can push a brick over 100mph with enough horse power. In 1976 at OP sail in New York, outside the harbor. I tried to catch the carrier USS Enterprise with my 50= MPH 16 Donzi and she pulled away in a hurry. Now Stang You need to back off a little. You can still use it as a family boat- there is no law that says you have to drive full bore! Now if your mech can't make it have manners at slow speeds GET ANOTHER one because he isn't worth beans. As Garry Grimes would say" if you can't drive it you can't race it. You had the purse strings so you let it get out of hand. I really think you don't drive that 25 foot pad at over 100!!! Been there and I was just lucky. As I said before the kind of ponies your putting in that block is not a good idea. AT 750hp that block becomes fragile. Not trying to be dad but life is too short The vest is nice but not bullet proof. You still have time to back off. It is easy to detune with a minimum of $ and time.

I tend to agree with Grizz. It is a nice big boat and you can still enjoy it with a milder tune. Throw in some smaller injectors, a MEFI 4 and be done with it. You can have a reliable package that has one fat cruise and blow the sox off of most on those special occasions.

If you start feeling like you need more in a couple of years and really love the hull, well you can strip it down, beef up the glass, up the beans and let her rip.

You are so close, it would be a pity not to finish it properly and let the family enjoy it.

There are a number of folks on this site that have boats that can take them to uncomfortable and dangerous speeds if they like. They probably go there on those special occasions and just enjoy their boat the rest of the time.

I have no doubt that my 26 will be a handful at full throttle. When I had my 27, I would open it up for a bit almost everytime I went for a ride. I won't be doing that anymore. Now I will have fun cruising slowly at 60 and when the need comes up run smartly to 75 without really even standing on it. That will be cool. Your setup will be able to do that easily as well.

[SilverBack]

Ok...I am sorry...I am just getting pissed off about the whole thing. This computer just kind of set me over the edge and my wife and girls are not really acting to excited about the thing being so loud and who would have thought that a procharged engine would have that blower lope to it. I mean it will sound really cool to me but it will not be easy to dock and it is going to be very loud. I have had no luck finding a set of mufflers. The CMI mufflers open up at 1800 RPM's is what I have been told. That is not going to do me any good. I guess that I will feel better when I get a chance to ride in the boat or even hear it run but I don't like moving this slow and it is getting on my nerves.

MJW...where I boat the water is like glass most of the time. I am not going to be jumping waves or anything like that.

I was just thinking about going to the lake with this big ole loud blown big block boat and some little Allison pulls up besides me and smokes me and the conversation that would take place afterwards.

I guess I just need to take Buzzilla and Grizz's recommendation and CHILL!!!

[mjw930]

The CMI's do open up but anything you find has to open up at some point or else you have to detune your motor. I don't think there's anything in your HP range that won't rob power without opening (or blow off the back of the boat ;) ).

I thought they were progressive in how they opened and even wide open they provide a baffle that will drop a few db's off. At idle they work great and in reality, that's typically where you want to quiet things down the most.

I've talked to 2 people who have used them and both love them, that's the only reason I recommended them.

[BlownCrewCab]

I don't know why your making any boost at idle, arent you only making about 5-6-7psi at wot? At wot my truck runs 7.5 to 8psi at 6200rpm and has vacuum at idle, not boost. what gives?

Also, even if you have have some blower lope when docking as long as it stays running there shouldn't be a problem. it's stalling that will Screw you up.

Now, if you want this boat to go 100mph I'll hook you up with Jim Arvis, He's the tech inspector for OSS and the Best single engine (offshore) V bottom driver there is,(he's in the APBA Hall of fame) I won 2 National Championships with him driving (me throttling). He can take a chinewalking machine and make it run very stable just with steering inputs, by riding with him and learning what/how he does it would help you allot. even if your only going 75-80mph.. It's not a good idea to go blazing across the water "Hoping" your Okay. you need to have done it with someone who knows whats Okay and you experience it a few times. I'd gladly do it with you, but going that fast I only throttle, not drive. But I'll go with you if you want/need. Jim lives in VA, Has a house in Fl and is at every OSS Event if you can get to one, let me know.

Your almost done, don't give up.....

[SilverBack]

I think he has the 7 psi pulley on there Michael. I don't know what is going on down there. I have not seen the engine run at all and I have been trying to stay out of the way. I think a lot of the problem was the big low impedence injectors and the piece of crap computer. I am going to high impedence injectors and MEFI 4 and the 2 bar map sensor so maybe that will help. The old computer would run great and then crap out and run terrible. Who knows??

I guess all of this will be over soon. I am going to take you up on going for some driving lessons.

[BUIZILLA]

stang, I have been following this buildup with a concerned, and quiet, posture...

IMO, your engine combo is a mess. The cam selection is a disaster. The EFI setup thinking is off the wall, and now your changing it AGAIN.

You need to visit the engine guy, and get some straight scoop's.

He's not doing you right. He see's an open checkbook, and he's experimenting/playing/practicing, at your expense.

Sorry for being so blunt.

[The Hedgehog]

Those CMI's that 930 was discussing do work and can handle some real power. I don't think that muffling it around the dock will be hard to achieve. There are plenty around with motors up to 950+ hp or so that use mufflers. Once you get going, the sound will be directed backwards and it is not too bad. You may want to re-consider that platform extension:doh:
Once you drive it some you will figure it out.


Blower lope with a centrifugal blower, I have actually had it happen too. I think mine was a confused ECU on a cold day. Typical blower lope is caused by fuel puddling in a big roots blower. I could see that being an issue with those giant injectors and your big intake.

You are soo close. You will get there.:wink: In the end, you will have the baddest 25ZX in the planet. That is pretty cool in my book.

[SilverBack]

Buz,
I think you are right!! I have talked to him but he is always running and in a huge hurry when I try to talk to him. He is a very nice guy and I really like him but in my opinion the boat should be in the water right now. The problem isn't the engine builder it is the tuner. When I look around his shop I see a bunch of Mercury racing engines and I have seen a couple of Ilmors but nothing oddball like mine. Maybe he is out of his compfort zone?? I have never been throught anything like this with an engine before. Usually you go to the Dyno and the same day you are ready to go. This engine has been on and off the Dyno stand for over a month. I don't understand. I think that is part of my problem. This Gorilla setup is very unusual.

As for the cam I don't know how you know what is in there it is hard for me to keep up. But here are my cam specs on the cam that is in there now.

Lobe center angle: 114
Lobe centerline: Crank 110
Intake duration: 231
Exahust duration: 239
Lift:.618
These specs are at .050

If you were buying a new computer and wireing harnes would you go with MEFI 4??? I am getting ready to spend another 3 to 4K so I would like to get it right!!


I have had a bad feeling about things for the last month or so but just didn't want to admit it to myself. I think that is why I am wigging out. There is no way it should take this long to tune an engine.

[The Hedgehog]

stang, I have been following this buildup with a concerned, and quiet, posture...
IMO, your engine combo is a mess. The cam selection is a disaster. The EFI setup thinking is off the wall, and now your changing it AGAIN.
You need to visit the engine guy, and get some straight scoop's.
He's not doing you right. He see's an open checkbook, and he's experimenting/playing/practicing, at your expense.
Sorry for being so blunt.

Wow, I hope that he is not doing all that on Keith's dollar!

He should make good on that.

My engine builder ran into a couple of road blocks too. He had to spend a little more time than he thought chasing around special parts and adapting things. He sent me a few e-mails to keep me posted and then called me to assure me that he was not going to charge me for a couple of lessons he had to learn about what it takes to extract big power from a 502 MPI.

I hope that your engine builder makes it good for you. If he values his reputation he will.

[The Hedgehog]

Buz,
I think you are right!! I have talked to him but he is always running and in a huge hurry when I try to talk to him. He is a very nice guy and I really like him but in my opinion the boat should be in the water right now. The problem isn't the engine builder it is the tuner. When I look around his shop I see a bunch of Mercury racing engines and I have seen a couple of Ilmors but nothing oddball like mine. Maybe he is out of his compfort zone?? I have never been throught anything like this with an engine before. Usually you go to the Dyno and the same day you are ready to go. This engine has been on and off the Dyno stand for over a month. I don't understand. I think that is part of my problem. This Gorilla setup is very unusual.

As for the cam I don't know how you know what is in there it is hard for me to keep up. But here are my cam specs on the cam that is in there now.

Lobe center angle: 114
Lobe centerline: Crank 110
Intake duration: 231
Exahust duration: 239
Lift:.618
These specs are at .050

If you were buying a new computer and wireing harnes would you go with MEFI 4??? I am getting ready to spend another 3 to 4K so I would like to get it right!!


I have had a bad feeling about things for the last month or so but just didn't want to admit it to myself. I think that is why I am wigging out. There is no way it should take this long to tune an engine.

$3 to $4k sounds kind of steep for a MEFI 4 and a wiring harness.

My builder and a whole list of some of the other respected guys use a MEFI 4 for big power.

No, it should not take this long to tune it. Before you get too upset, remember that you have bought the boat, made some major changes and done a whole bunch of work. I actually think that your builder needs to slow down and think some thing through.

My builder may not be the fastest on the planet and I am ok with that. He spent days agonizing over injectors and small details like that. Hopefully it will pay off and we will get on and off the dyno quickly. If not, he says that is his problem not mine. So far, so good.

[BUIZILLA]

hog, is Eddie doing your engine?

[BlownCrewCab]

Isn't there a equation for the injectors he should be using, Cyl volume, rpm, Lbs of air, etc... why are they just guessing what to use. as long as your IDC (Injector duty cycle) is below 90/100% the smaller ones will be fine, I think the motor guy should have maxed out the stuff he had before assuming he needs bigger anything.

[BUIZILLA]

Isn't there a equation for the injectors he should be using, Cyl volume, rpm, Lbs of air, etc... why are they just guessing what to use. as long as your IDC (Injector duty cycle) is below 90/100% the smaller ones will be fine, I think the motor guy should have maxed out the stuff he had before assuming he needs bigger anything. there is a very basic, and easy, starting equation... 1/2 lb fuel, per hp/hour

IOW.. say you KNOW you have 700hp 8 cyl air pump to size up

an injector doesn't know what engine it's for, or what color it is, or what size bra your wife wears, it just reacts to ms input and gradient pressures...

700 divided by 1/2, divided by 8 = 43.75 pph injectors at 100%duty cycle... now *I* like to see a +20% comfort window for blown applications, so that = 52.5 pph. If Delphi still sold them, which they don't, they had a perfect 52# injector for this setup which were saturated coil high ohm injectors... good idle manners, linear flow #'s... I personally like low ohm, peak and hold coil injectors, they run stronger coils and have faster response time, but usually require 6 amp individual injector drivers for each injector in the ECU... what you MUST watch for, and I can do this inhouse, is flow the injectors in 2# increments to see if they stall the coils, or nose over on the flow, this will melt things purty quickly.... you would be surprised that there ARE injectors out there that flat out just quit pumping at pressures over 57-60 #'s, the coil stalls, while others can cruise past 100# at will... you do NOT want MSD or some Rochester injectors.... when you take a fat injector and try to lean it down to idle itself, when it gets under about 2.1-2.3 ms or lower, it starts dripping droplets instead of any atomization, puddling is not good, kinda like using a 3 circuit Dominator, they just drip chunks of fuel from the downleg booster's... Once you get over about 60 pph injectors the idle gets sloppy, unless your on alchohol... I like Siemens, Denso or Bosch injectors... higher pressures do NOT necessarily equal more volume on a delta P pressure rise scale at a given rpm load... a very good workhorse test injector is the 803 Bosch for a Turbo Porsche, it is rated at about 43 pph, but it can run forever, it is low impedance however... Ford Motorsports Catalog has good pricing on Bosch injectors, if you can get them for your size rating, most of those are high impedance. You should call Tim Marren at Marren Motorsports in CT for another opinion, he's a good guy. I have probably, at this point, flowed somewhere between 8,000-9,000 gas injectors on my equipment and probably over 150,000-160,000 diesel injectors..

[SilverBack]

Buiz, That is some very good information!! Thanks. Any ideas on the MEFI 4 versus anything else out there? Anything else I need to look at? Cam ???

[BlownCrewCab]

I think the 114lsa cam is a good blower cam and the fairly long duration should be bleeding off boost at idle to eliminate the blower surge. Is that cam info he gave you, or did you buy it?

[SilverBack]

MJW,
The CMI mufflers do seem to be the best out there!! I didn't mean anything bad about them; I was just hoping that they would not open up until I got to around 3500 RPM's. You always have some very good information and I didn't mean anything bad about your advice!

[SilverBack]

BCC,
I got the information off of the cam card. I bought the cam if that is what you mean. I have three of them now! All a little different.

[BUIZILLA]

can you email me copy's of those 3 cam cards?? I would like to see ramp speeds... do you have any head flow numbers?

[SilverBack]

Buiz,
I am out on the water right now so I don't have the cam cards. I do have the flow numbers from the heads.
Intake:

Lift inches CFM
.050 34
.100 80
.200 141
.300 212
.400 279
.500 333
.600 372
.700 401


Exhaust

Lift inches CFM
.050 30
.100 70
.200 135
.300 169
.400 219
.500 249
.600 272
.700 285

[SilverBack]

Buiz,
I forgot that I had some more information on that cam in my Dyno 2000 program.
IVO 5.5 BTDC
IVC 45.5 ABDC
EVO 57.5 BBDC
EVC 1.5 ATDC

I don't know if that will help you much????

[The Hedgehog]

hog, is Eddie doing your engine?

Yes, Eddie Young is doing my engine.

Anything I need to know? I had him do a few other things for me and so far he has been very good and upfront. A number of guys around here have dropped some real big bucks with and swear by him. He has spent a bunch of time telling me what he is doing and why. He has also told me about mistakes he has made in the past. To me he has been humble but confident.

[The Hedgehog]

there is a very basic, and easy, starting equation... 1/2 lb fuel, per hp/hour
IOW.. say you KNOW you have 700hp 8 cyl air pump to size up
an injector doesn't know what engine it's for, or what color it is, or what size bra your wife wears, it just reacts to ms input and gradient presures...
700 divided by 1/2, divided by 8 = 43.75 pph injectors at 100%duty cycle... now *I* like to see a +20% comfort window for blown applications, so that = 52.5 pph. If Delphi still sold them, which they don't, they had a perfect 52# injector for this setup which were saturated coil high ohm injectors... good idle manners, linear flow #'s... I personally like low ohm, peak and hold coil injectors, they run stronger coils and have faster response time, but usually require 6 amp individual injector drivers for each injector in the ECU... what you MUST watch for, and I can do this inhouse, is flow the injectors in 2# increments to see if they stall the coils, or nose over on the flow, this will melt things purty quickly.... you would be surprised that there ARE injectors out there that flat out just quit pumping at pressures over 57-60 #'s, the coil stalls, while others can cruise past 100# at will... you do NOT want MSD or some Rochester injectors.... when you take a fat injector and try to lean it down to idle itself, when it gets under about 2.1-2.3 ms or lower, it starts dripping droplets instead of any atomization, puddling is not good, kinda like using a 3 circuit Dominator, they just drip chunks of fuel from the downleg booster's... Once you get over about 60 pph injectors the idle gets sloppy, unless your on alchohol... I like Siemens, Denso or Bosch injectors... higher pressures do NOT necessarily equal more volume on a delta P pressure rise scale at a given rpm load... a very good workhorse test injector is the 803 Bosch for a Turbo Porsche, it is rated at about 43 pph, but it can run forever, it is low impedance however... Ford Motorsports Catalog has good pricing on Bosch injectors, if you can get them for your size rating, most of those are high impedance. You should call Tim Marren at Marren Motorsports in CT for another opinion, he's a good guy. I have probably, at this point, flowed somewhere between 8,000-9,000 gas injectors on my equipment and probably over 150,000-160,000 diesel injectors..

That is some pretty heavy info. I have heard the layman's version of that. We are going with Siemans injectors on mine. I am pretty sure that is what Tex is using as well per recommenation of Marc Boos.

I have heard that you spent a good bit of time flowing and dealing with injectors. That is some pretty fascinating stuff.

[BUIZILLA]

hog, Eddie is good people, never dealt with him myself, but the big players around you swear by him....

at this point, stang needs another doc's opinion, based on what i'm reading herein... I prolly shouldn't have castrated the cam choice that hard, but I *may* have gone another way on this.... still not sure what overlap it has.. I also can't imagine, in any family usage instance, putting together a package that has 0 vacuum or even positive pressure at idle (did I read this wrong?)... that's so f'in stupid it defy's reality.. also, not sure if the heads were flowed at 25" or 28" of mercury, but they don't make sense either.. I could care less what a head flows at .700 lift if the valve spends 95% of it's time at the .100-.200-.300 elevation. Air speed and velocity is MUCH more important. This builder is doing what HE wants, not what stang NEED'S.

sorry to ramble.. :doh:

[SilverBack]

I don't know about the vacuum vs. boost at idle. I think that was just an assumption. It has super charger lope. I think David thinks it has more to do with the injectors and the computer than anything to do with boost at idle.

I really don't want to dump on David. I AM the one that ordered this oddball Gorilla procharger system. I am sure if I would have gotten a regular 502 procharger setup there would not be anything to talk about. He is also not learning any of these lessons for himself; he will probably not ever see another one of these setups.

The flow numbers are with a 2 1/8" pipe and 28"of H2O. I bought the heads too. He did not pick them out. They were free.

He has not charged me for any of this tuning yet but because he is not charging me he wanted to get away from this oddball computer so he could get it done and over with.

This cam didn't even come from him it came from my engine builder. It seems to make good torque on the simulator and it does great on the Dyno. It was idling great the first day but it has not been acting right since. I don't know of any mechanic that like getting a bunch of oddball stuff dropped in there lap and told to make it work. I get ahead of myself sometimes but I just hate waiting around for things to come together. I saw this system and it was very "cheap" so I bought it. I guess that I need to take some of the blame for this dragging out.

Hey, If things don't work out like I want them I can always take the blower and fuel injection off and put on a manifold and carb and some mufflers and go tubing with my 550 to 600 HP family boat!

[BUIZILLA]

is the ECM set up for high impedance injectors and your using low imp's ?? is it sequential or batch fire? if it's sequential , how/where did you reference the #1 cyl trigger point?

[SilverBack]

The old computer used low impedance injectors. David said that the MEFI 4 uses high impedance injectors. That is why I have to change my computer and injectors. Because the MEFI 4 will not work with the low impedance injectors. That is my understanding anyway. I am not a mechanic or anything close to being a mechanic so I have no idea about what is firing where!!