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View Full Version : Raised X dimension will i have cooling problems?



tommymonza
06-24-2014, 03:59 PM
Hi Guys

Thinking about raising my X dimension 2 and a half inches while i am doing some transom work. I look at it as a easy speed gain no brainer but now I am concerned about cooling problems .

My current X measures 7.75 from the propshat to the bottom which I believe is stock height.

I like the idea of raising because of all the positive things I have read on here about the handling improving and speed gain isn't bad either

The boat is not a Donzi but I posted here in the Donzi talk to get the expert advice knowing most you guys probably don't look in the talk other boats thread, so I apologize for intruding.

Anyways the boat is a 19 foot 1978 Baron which my older brother designed and built a few before shutting the doors and eventually selling his molds to powerplay/Powerquest to become their 185xlt.

Anyways the bottom is a rounded V very similar to the Donzi 18 with no hook and just a little rocker so it does not need any positive trim.

I have a Brand new Gen2 Alpha and transom assembly that I am going to mount on the boat that has not been in the water for 20 years and thought if I am going to the trouble why not raise it.

Concern is I live in SW Florida where our water temps can get into the high 80s if I will be sucking some air and have cooling problems.

After reading the poor handeling issues experienced by people putting on lower water pickup nosecones I will not be doing that.

One motor I have for it is a brand new Mercruiser 305 220Hp 2 barrel that I had bought for another project .

My original motor is a 1978 260 bored 30 over with a pretty hot cam built by a reputable marine builder here in Naples 20 years ago with 202 intakes and a little stock head porting with a rejetted Quaddrajet on the stock intake. I also have a new set of Elbow top CMI headers on this motor too.

The boats ran 58 on radar back in the day with the 260hp .

I think the 355 i have built may be worth 320hp with the Exhaust so maybe 65mph with the stock x height and maybe 70 with it raised.

I am leaning towards putting the 305 in just for the low key quiet Y pipe running for a while .The 355 motor is in the boat but I have never ran it other than on the hose and I would want to rerig it before I ran it at this point.

Anyways My thought was raise the X 2 1/2 inches because that is all the further I can go if I ever want to run the 355 with the headers or they start to exit thru the rubrail without getting new tailpipes made.

If I ran the stock 305 with the Vortec heads with just a little more cam and a 4 barrel going thru the Y-pipe and a raised X I was hoping for maybe 58 to 63.

Raised X is good for at least 5 mph right?

Sorry for rambling just wanted to relay all the info I have to you guys because I have some other ? too later on.

I have been doing searches and pouring over the threads for hours gathering info ,just looking for the latest news.

By the way if this wasn't one of my brothers design I would be in a 18 Donzi, still the hottest looking boat out there.

Thanks

VetteLT193
06-25-2014, 03:16 PM
The Gen 2 alpha doesn't have low water pickups like the new bravos do?

I think I'd try it, watch it, and if you do have an issue put a nosecone with a low water pickup on. They aren't too expensive if it is needed in your particular case.

Just Say N20
06-25-2014, 03:47 PM
First, I "bleed" Donzi as much as anyone, but I have to admit that the Baron/Powerplay 185 XLT is one of the best handling, best riding boats I have ever been in. They are remarkable.

If you are going to the trouble to redo the transom, install a transom mounted raw water pickup and a raw water pump on the front of the engine. Problem solved.

I know nothing about Bravos, or if they have an impeller in them like the Alpha does, or what would be involved in not using it.

I think you could get a raw water pump and transom pick up for around $600.

MOP
06-25-2014, 05:50 PM
I was up 16-1/2+ on my Tempest 22, it had an Alpha with side pickups. I had no cooling issues hope that helps with your thoughts.

gcarter
06-25-2014, 06:19 PM
First, I "bleed" Donzi as much as anyone, but I have to admit that the Baron/Powerplay 185 XLT is one of the best handling, best riding boats I have ever been in. They are remarkable.

If you are going to the trouble to redo the transom, install a transom mounted raw water pickup and a raw water pump on the front of the engine. Problem solved.

I know nothing about Bravos, or if they have an impeller in them like the Alpha does, or what would be involved in not using it.

I think you could get a raw water pump and transom pick up for around $600.

What Bill said.
Also, w/the transom pickup, you can get rid of the too small Alpha impeller.

tommymonza
06-26-2014, 01:38 AM
Thanks for the feedback guys appreciate it . I usually hang around OSO but they are all big boat/big buck guys there, I am far from that.

This is my 2nd Baron as I sold my 1st one I owned to someone who became a good friend who goes by baronmarine on OSO and Speedwake these days.

I moved to Florida 30 yrs ago and sold him my 1st one to finance my move to Florida.

Bought my 2nd one from a good friend who had it repainted poorly 20 tears ago and I had the 355 and the headers built for it back than . Work and Family and Life has kept it sitting for 20 years but recently I told myself I have to do something to make my self HAPPY.

So i i took the covers off and I am finally working on it.

The 1st one I owned Todd or Baronmarine built a mild 383 and installed an Arneson and what a difference ,he is at 77 with a poor 3 blade but most importantly it calmed the boat down as it has a ton of rocker in it.

Just looking to get it back in the water for now and thought the 305 would be nice and quiet, I like to go out and go for a sunset ride and have a beer or 2 and don't need a hey PULL ME OVER boat down here as they are on the hunt these days.

Nice to her from you guys thanks for the kindness. And JUSTSAYN2No if you want any other info or a old brochure be glad to send one to you just pm an address and that goes out to all you helpful Donzi freaks also if it interest you.

You know what the best thing I have noticed about Classic Donzi's and current Donzi's

They don't end up with some chitty swirly Dragon or other crappy Splotchy paint job on them. Just classic simple paint jobs that accentuate the beautiful lines .

It shows the Class of the boat and brand name and also the owners in particular.

The thing is with raising the X if it atarts to add up I can buy a Arneson with hydraulic steering and a half way decent prop and transmission for 5 to 6 thousand .

What I could save on not building a hot over the top motor i could spend on this drive setup just a thought. Always been an Arneson freak when the debuted it in Powerboat magazine in i think 1982 on a 18 Pachanga and claimed they were getting 72 mph out of a stock 260hp 350 when all of th other 18 were running 58 with are old MRs with Cleavers andwe thought we were hot and fast.

tommymonza
06-26-2014, 02:04 AM
Best oldschool Donzi pic i have seen . My dad had a 26 Monza and there was a 28 Cigarette and a few 24 Nova's in Grand Haven back in the early 70s bit there was a yellow Donzi barrel back that was named FOXY LADY that was the true Hell Raiser there back in the day. I have a pic of it sommewhere I will find it and post it but this boat sure looks like it.

mattyboy
06-26-2014, 06:23 AM
that's a 16 not a barrelback :)

Moody Blu'
06-26-2014, 07:59 AM
Best oldschool Donzi pic i have seen . My dad had a 26 Monza and there was a 28 Cigarette and a few 24 Nova's in Grand Haven back in the early 70s bit there was a yellow Donzi barrel back that was named FOXY LADY that was the true Hell Raiser there back in the day. I have a pic of it sommewhere I will find it and post it but this boat sure looks like it.

that looks like me!

http://i35.photobucket.com/albums/d194/beerock69/me%20pics/boat/DSCF0011.jpg (http://s35.photobucket.com/user/beerock69/media/me%20pics/boat/DSCF0011.jpg.html)

http://i35.photobucket.com/albums/d194/beerock69/me%20pics/boat/DSCF0001.jpg (http://s35.photobucket.com/user/beerock69/media/me%20pics/boat/DSCF0001.jpg.html)

Scott Pearson
06-26-2014, 08:09 AM
2.5 on an Alpha. I would be very concerned about handeling issues. Forget about the water pickup. I would think long and hard about going that high. The very small amount of speed you will gain will not be worth the handeling that you are going to lose.

seano
06-26-2014, 09:38 AM
2.5 on an Alpha. I would be very concerned about handeling issues. Forget about the water pickup. I would think long and hard about going that high. The very small amount of speed you will gain will not be worth the handeling that you are going to lose.


I couldn't agree more on all points. There are not enough gains to be had here to outweigh the negatives in handling and planing. I've been there and done that on 2 boats already.

BUIZILLA
06-26-2014, 10:04 AM
the SS drive is 2 3/4 shorter

the absolute best bang you can do to a 16 or 18

handling was flawless with the SS, in fact, it was MUCH better

water pressure stayed the same too

MOP
06-29-2014, 07:43 PM
I couldn't agree more on all points. There are not enough gains to be had here to outweigh the negatives in handling and planing. I've been there and done that on 2 boats already.

I could not disagree MORE! The SS is 1/4" and handles better, there is not a shorty owner out there that will tell of any bad handling habits. Look at the later 22's where the dropped the engines down an ended up with a bunch of hopping bunnies which is only cured with a shorty. Many know I was a marine tech for over 30 years and have been in the field over 50 years, I setup hundreds of outboards the higher you raise them the faster they run that is until you run out of water to the pickups. Take a deep breath read up then come back and comment!

Darn near forgot how my 22 ran on rails with the Blackhawk that sure runs deep!

Scott Pearson
06-30-2014, 06:57 AM
MOP....Re Read the post. He was NOT talking about a shorty. He was talking about a regular Alpha Drive. Jim is the one who suggested the Alphia SS and the performance of the drive.

What we are ALL saying is that going 2.5 up on a REGULAR Alpha will cause huge issues. He should leave the "X" where it is and use an Alpha SS.

Your the one who needs to take a deep breath...sober up then comment!

And just because you have been doing someting for 30 -50 years.... DOES NOT mean you have been doing it right for 30-50 year!

I hear that crap every single day in my field...and those people are the ones who have no clue what they are doing.

MOP
06-30-2014, 03:24 PM
Standard Alpha from the get go no argument, no comment on you wealth of knowledge!

VetteLT193
07-02-2014, 02:43 PM
Isn't the SS basically a short Alpha 1 with a nose cone? What other differences are there that would warrant the expense of an SS over a regular Alpha if one is already redoing the transom?

seano
07-02-2014, 03:09 PM
Isn't the SS basically a short Alpha 1 with a nose cone? What other differences are there that would warrant the expense of an SS over a regular Alpha if one is already redoing the transom?

definitely not a "short alpha with a nose cone". the lower is one piece cast aluminum.

My understanding of the SS is that it is a modified Alpha upper married to a modified CLE lower - with the CLE coming from the Mercury outboard world and it simply bolts on to your existing Alpha transom assembly. Adding the SS essentially does what Tommy is looking to do WITHOUT making any modifications to ANYTHING.

To me the benefit here is that if you realized after reglassing and recutting the transom, modfying the hull or drive for low water pickup, re-doing the motor mounts - that the X was too high for your liking, you are looking at a much more expensive "oops..." With the SS, you simply unbolt it, put your stock Alpha back on, sell the SS and move on...

OFFSHORE GINGER
07-02-2014, 06:55 PM
MOP....Re Read the post. He was NOT talking about a shorty. He was talking about a regular Alpha Drive. Jim is the one who suggested the Alphia SS and the performance of the drive.

What we are ALL saying is that going 2.5 up on a REGULAR Alpha will cause huge issues. He should leave the "X" where it is and use an Alpha SS.

Your the one who needs to take a deep breath...sober up then comment!

And just because you have been doing someting for 30 -50 years.... DOES NOT mean you have been doing it right for 30-50 year!

I hear that crap every single day in my field...and those people are the ones who have no clue what they are doing. Scott , this post was way out of line or should i say your comment's about sobering up , and past experience , and who really needs to take a deep breath .