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View Full Version : my brother says I "need" 1,000 horsepower



Digger
03-24-2002, 06:54 AM
My brother (Howe, pronounced How-wee, just joined the board :) ) keeps saying "wouldn't it be cool if you had over 1,000 hp?" well...he's right :D

My 502's are stock out of the box. Bravo 1's likewise. What I would like to hear from the assembled expertise on this board is your opinions on supercharging these engines. I have done some reading on the many units available out there, from mild to wild. I don't want to go crazy on the boost. I would like to avoid making any internal engine changes. how much boost can the 502 take without modification? I understand there would be changes to the EFI system, (different chip or module?) no problem there.

I would also need new drives, would prefer not to put over 500 hp through the Bravo 1's. I understand they are rated for up to 500 hp only. which drives to get?

Also, I would prefer not to modify my engine hatch. I dont want two huge scoops that say "look what I got" I would prefer to keep the exterior look of the boat original. I imagine I may have to make provision to get more air into the engine compartment.

I don't have any particular speed I want to reach. Around 75 sounds nice. She will do an honest 65 now. Also I have no particular quantity of horsepower I'm looking for. I just want more power, Scotty...

I look forward to hearing your opinions!! :D :D

BigGrizzly
03-24-2002, 08:57 AM
Digger, I have over 690 Hp from a 502 with a Procharger with maximum 5psi of boost. My engine is modified inside, only because I had the pieces. I won't get into which is a better super charger because all are fairly equal. This year I've seen Prochargers, Wipples and Vortex scattered. Most with minimal engine damage. All had one thing in common they were abused. In my own engine I dropped an inconel exhaust valve, but in no way was it the fault of the supercharger. After an analysis by a metallurgist it turned out to be a crystalline bad valve. This engine had over 185 hours on it. My suggestion is just bolt one on and don’t get radical. The Bravo will work fine providing you don’t beat on it like an offshore racer. Monitor your boost and keep it below 5psi after that the supercharger will spin too fast. This is what the problems really are—Rpms of the supercharger. I have seen all of them blown and there is one thing in common, too many supercharger rpms.

Since you only want 500 hp per engine keep the boost to 4.5 psi and your home free. All assemble and fit fine on stock applications. There is so much data out there for a 502mpi it is a simple bolt on task. Hope this helps and good luck. With the procharger and vortex you don't een have tr take of the intake manifold.

Randy

CDMA
03-24-2002, 02:33 PM
I agree with Randy. I would just put on a blower at about 5 psi. On a more or less stock 502 that should be good for 575-600 hp. The 454/502 magnums are very strong internal engines with forged cranks, 7/16" rods and forged pistons. I had originally planned to put a blower on a stock long block but I ended up having the long block built for the blower specifically. However I would have been totally comfortable with a 5 psi blower on a stock lower end. In terms of what blower to use they really all are good and bad in their own ways. If you were going to use a centrifugal blower I would use a procharger. First they are a bigger company then vortech, more units out there on the used market and I also have had great experience with their customer service. Mike Cromer there is wonderful to deal with. However if money was no, or less, of an object I would like to have a Whipple. I, personally, think they are the best design out there. I really like the whole screw blower concept as well as the cupronickel intercooler. But that is just me. I also have heard that Dustin Whipple is a wonderful to deal with.

Just m $.02

Chris

P.S. Keep in mind if you "only" want 500 hp a side that can pretty easily be done with a naturally aspirated 502. There is something really nice about a simple big carbed engine.

Digger
03-25-2002, 09:09 AM
great comments guys, thanks for taking the time to post them. I would be wary though, of not upgrading the drives. Now all I need is more money... :rolleyes:

Forrest
03-25-2002, 09:13 AM
Digger, I agree with your brother. Anything less than a 1000 hp just isn't worth messin' with! :p

Woodsy
03-25-2002, 09:29 AM
Digger,

Blowers are the way to go, if you got the cash.... if you have 502 Mags, you can probably go the naturally aspirated route... I would start with the exhaust, Stainless Marine makes a great product, then I would look into the Vortec Marine kits... reprogrammed ECU, K&N air filter, fuel pressure increase etc... these mods will put right about 450HP give or take, and will cost alot less than the 10K needed for the dual blower setup....

As far as your outdrives go... if it ain't broke, don't fix it. With a heavy boat such as yours, you just have to watch the holseshots... they put tremendous stress on the drives. If they break, then exchange them for an upgraded set... until then... have fun!

Woodsy :D :D

Digger
03-25-2002, 10:03 AM
hmmm...more excellent food for thought. As far hole shots go, I take it pretty easy. I like to bring the power on gradually, slowly shove her nose in the air and then let 'er growl her way out of the hole.

Does Vortec have a website?

thx for the info guys!!

Secret F233
03-25-2002, 10:26 AM
Well I might get kicked off the Board for this but :( . What about Turbo V8's My wife's Mitsubishi Spyder Eclipse can put out 242hp at 18PSI out of a 4 banger with a K&N, stock turbo & intercooler (that's up from a 141hp Base N/T platform) why not Intercool & turbo a boat they do it to mustang's, camaro's, Big Rigs & Bulldozers?
Again please excuse my inexperience :confused: !!

Gale Banks And the 2000hp twin-turbo 454 that won the '74 Jet Boat . Nationals
http://fiss.com/BANKS/FIBANKS52.htm

entire article wild story on Gale Banks!!
http://fiss.com/BANKS/FIBANKS55.htm

http://www.bankspower.com

tt camaro
http://www.skulte.com/turbo.html

Howe
03-25-2002, 08:00 PM
You do "need" 1000 hp under your fist. As I promosed earlier, I'll help with the $$$ :)

33 Daytona
03-26-2002, 12:13 PM
Here is my $.02:

I have a 28zx with a 454 mag and a Whipple. I run 6 lbs. of boost on 92 octaine gas 592bhp @5300rpm. I have had it for 1 1/2 seasons and no engine problems. The thing about a Whipple is as soon as you hit the gas the boost will kick in. If you go with a procharger you have a lag before you hit the rpm and it kicks in. The guys a whipple are the greatest, I say this because I boought the Whipple used from a guy in the Ozarks and he didn't send all the parts and the guys at Whipple were more than happy to overnight them to my mechanic. I have frinds with Prochargers and have had some problems with them and getting parts is not so easy because they are built as a complete unis so if you need a single part you have to wait till they are creating that part to get yours.(this is what the local Procharger
mechanics has told me)

In regards to the lower unit I blew the gears out of mine because I got a bad rebuild. So This time I had my mechanic rebiuld it and he put diesel gears in it for added durability. Also if you dont already have drive showers you will wont to get them with a blown engine. They are cheap.

Sorry so long!

P.S. I gained 14 mph with the Whipple

33 Daytona
03-26-2002, 12:18 PM
Here is my $.02:

I have a 28zx with a 454 mag and a Whipple. I run 6 lbs. of boost on 92 octaine gas 592bhp @5300rpm. I have had it for 1 1/2 seasons and no engine problems. The thing about a Whipple is as soon as you hit the gas the boost will kick in. If you go with a procharger you have a lag before you hit the rpm and it kicks in. The guys a whipple are the greatest, I say this because I boought the Whipple used from a guy in the Ozarks and he didn't send all the parts and the guys at Whipple were more than happy to overnight them to my mechanic. I have frinds with Prochargers and have had some problems with them and getting parts is not so easy because they are built as a complete unis so if you need a single part you have to wait till they are creating that part to get yours.(this is what the local Procharger
mechanics has told me)

In regards to the lower unit I blew the gears out of mine because I got a bad rebuild. So This time I had my mechanic rebiuld it and he put diesel gears in it for added durability. Also if you dont already have drive showers you will wont to get them with a blown engine. They are cheap.

Sorry so long!

P.S. I gained 14 mph with the Whipple

BigGrizzly
03-26-2002, 08:57 PM
28ZX, I have a Procharger and there is no lag whatsoever. The fact is I know many people who have them and have the same result. They are just like the Wipple and are a direct drive, therefore there is some boost at all rpms and no lag. Turbos have lag. Because the turbine doesn’t catch up with the engine rpms right away. As for parts they are all easy. The belts can be had at NAPA. The hoses are common pluming supplies. The supercharger is sold as a complete unit onlt, and they have all the stock of intercoolers.
No slam Chris but Procharger came out much later (1996) than Vortec.Vortec superchargers came about in the late 1970 early 1980. The CEO worked for American Honda and aided in the constriction of the Honda Hawk Bonneville stream liner. Vortec has been making all kinds for years. However Procharger(ATI) has advertised specific kits since 1996.

Randy

CDMA
03-26-2002, 09:07 PM
I agree with Griz. I bought my procharger knowing I would have some bottom end lag. however upon getting to the dyno I was amazed how quickly the boost climbed as well as the flatness of the torque curve. Now I have no actual in boat experience with this engine yet so I guess I will see then but the dyno was really promising in that regard. Anyway I figure the arneson will cavitate at low rpm anyway.... wink wink wink

No question Vortech has been around for a lot longer. I looked into some of their stuff for my truck and was very impressed. All I was trying to say is that procharger is bigger in the marine market then Vortech is. Actually I think they sell more marine superchargers then any company but not %100 sure.

Chris

33 Daytona
03-27-2002, 06:27 AM
Griz,

I'm glad you have had a good experiance with you Procharger I'm just going from what I have been told from dealers of them and friends that have them.

I guess i am a little biased from a friend that has a procharger and couldn't keep a belt on it. They would break and he was left stranded where ever it broke. When he trid to talk to the President of Procharger about it in the Ozarks (he just happened to run into him) and he didnt want anything to do with him. The two groups of guys about had it out. Now there is always 2 sides to a story so take this one with a grain of salt. I have but I think it had a little to do with my desicion when I had a 18 ft Bayliner and he had a 272 Baja I had to tow home a couple of miles after he blew a belt. Whipple, if you blow a belt you can keep driving.

Digger
03-27-2002, 08:32 AM
great discussion guys, keep it comin'!

Scott, the naked idea certainly has merits...

Intercoolers: I think I know what they do (cool intake air=denser air for more efficient/higher power explosion inside the cylinders) but should they or are they considered a requirement when supercharging? My guess would be no. Would like to hear other's opinions...

p.s. why the hell are beefier drives (IMCO, others) so freaking expensive?? :mad:

Jamesbon
03-27-2002, 08:49 AM
Very simply put, big cubes and carbs = LOTS of hp and less $$ as compared to any type of forced induction!

Although a big roots blower doesn't look half bad atop of a 540...

As for the drives, get a pair of Arneson's, they won't break...

seano
03-27-2002, 11:12 AM
Griz, Chris,
Mebee you guys can help me here...I just bought a boat with 420s mated to TRS drives and was thinking in the future of adding a ProCharger...What do you guys think? Pros, Cons???

BTW, I have chosen ProCharger because I don't want to modify the hatch.

CDMA
03-27-2002, 11:38 AM
Digger,

The intercooler was the reason I used procharger. As I have said before I really would love to try a whipple but they are just soooooo expensive it wasn't possible. So that left me with Roots or Procharger. I thought about running an intercooled roots blower but I just can't deal with the hatch issues. I don't really care if I need a little dome or something but a full pro-stock scoop just wasn't going to do it. I want these people to be suprised when I go by at 90. So then I was down to Roots blowers non-intercooled or prochargers. Now this is just my opinion and that for sure means it could be wrong but I do not like the idea of running a blower without an intercooler. Blowers heat up the air tremendously and the longer you are on it the hotter the air gets. The hotter the air the more likely you get detonation and that makes a really big mess. I know mercruiser has done it sucessfully but I don't base my opinions on what other people have gotten away with. To run a non intercooled supercharger on their engines they lower the compression way down ( not a horrible idea) but they still run very low boost. On top of that they ( on the HP 575) have a computer set up to monitor for detonation and so forth. After all this is said and done that engine still "only" makes 550 hp. Now I know that is a lot of power but sure way off the numbers of an intercooled system. I mean both mine and Griz's engines are relatively mild: 9 to 1, 5 psi, etc etc and I get 600+ out of a 454 and he gets almost 700 out of a 502. So that led me to the procharger. There still is the issue that the blow through carb system is difficult to set up right but I think it can be done in a satisfactoy manner. If not I will go to a laptop based MPI set up and do it that way. I guess it is just part of the learning curve and for me the next step is to see how this thing actually works.

Sean,

Well I really want to wait to see how well mine actually works to offer a recommendation. However that should work pretty well. My 454 actually puts out 420 hp in stock non blower form. Adding the blower at 5 psi at 4700 and 5 psi at 5000 rpm brought me right up to 615 hp. I would venture a guess that is what you would see as well. Take a look at OSO there are a couple used carb kits for sale pretty cheap.

Did you buy that 38 that was at the run this summer? That boat was awsome looking and sure sounded sweet. I think we REALLY need to exchange rides now!!!

Chris

Digger
03-27-2002, 11:59 AM
Chris, good stuff there, thx. I didn't realize the supercharger would heat up the air that much...

researching strengthening up the Bravo 1's without robbing a bank to pay for completely new ones...

seano
03-27-2002, 12:26 PM
Thanks for the info Chris, I know you'll keep us updated. I bought an 87 Cafe Racer(there are pics and details on the OSO board)...hope to see you areound this summer!

Digger
04-01-2002, 08:15 PM
well, after considerable research, I have determined the following:

--the "naked" route won't get enough horsepower to make a considerable difference in performance. My boat weighs in around 10,000 lbs...adding 50-75 hp on each motor won't get me much
--5 psi Prochargers would be my choice, along with an IMCO drive upgrade
--having two engines is cool until you do the math on what it will cost to do the above... the upgrade will have to wait

thanks for the input all, its on the shelf for now but not forgotten