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-   -   Supercharger for 502 EFI (https://www.offshoreonly.com/forums/general-q/210456-supercharger-502-efi.html)

Philledan 06-07-2009 12:50 PM

Supercharger for 502 EFI
 
Guys,

i currently have a 38' scarab with dual mercury 502 EFI's in it...Im looking for more power, so i need a supercharger. Anyone have any ideas on which blowerkits are good for the 502. Supercharger USA have a popular 8-71 blower kit which produces around 840hp! im looking for something like this, however, i had never heard of supercharger USA before...so i would like you guys to give your opinion on them, and wheather there are better alternatives?

Thanks!

hoozeyurdaddy 06-08-2009 08:36 AM

i believe supercharger usa is not a manufacturer , the just sell the products, what are you doing for a fuel sys. staying efi or going carb, what does this kit consist of?

niceguy 06-08-2009 08:48 AM

With fuel injection your choices are only limited by your budget, but to get 840hp out of a stock 502 by simply adding a blower? Ummm, I disagree... unless you are gonna run race gas and even then, I dunno?

Anyways, the cheapest route is going to be a procharger system.

Second is the whipple, but more expensive.

And finally you can always go the roots blower style with custom throttle bodies and aftermarket FI system.

Keep a few things in mind here before you buy any parts: you will always have to upgrade existing systems to make more power. Fuel system is number one, in your case the ecm is number two... a good tune is the key to power and longevity. Three is gonna be oil cooling system, and four is gonna be exhaust.

Now that your making tons of power, the drives are next. If you have B1's like I do.... I think they are only rated for like 550hp. So with the torque of the supercharger, either be prepared to be easy on the sticks or you'll be doing drivews immediately after you finish making tons of power. But what drives to go with? That, I cannot tell you... but I would like to know myself.

This is my two cents.

Jeff P31 06-08-2009 11:04 AM

Your wallet is the limit to the power you can make ! But to just bolt on a supercharger and make 840hp I say BS !!! If you do all the work yourself it takes a lot of time to get it set up right, if you hire it all out it takes a lot of money. I have seen a lot of guy's go down this road some with good results and some just said to hell with it and got right out of boating. It sure is hard to beat stock power , turn the key and go . And yes I have been there with 502 's with prochargers . Just my .02 Jeff

ZXXX Donzi 06-08-2009 11:16 AM


Originally Posted by Philledan (Post 2882588)
Guys,

i currently have a 38' scarab with dual mercury 502 EFI's in it...Im looking for more power, so i need a supercharger. Anyone have any ideas on which blowerkits are good for the 502. Supercharger USA have a popular 8-71 blower kit which produces around 840hp! im looking for something like this, however, i had never heard of supercharger USA before...so i would like you guys to give your opinion on them, and wheather there are better alternatives?

Thanks!

I started out with a 502 EFI as a base. If you want to pull out 840hp you will have to do a bunch more than slap on a big roots blower.

Getting any more than 575 to 600 hp and keeping it alive will require some pretty serious mods. Been there before.

Pure Energy 06-08-2009 01:49 PM

He never said he was looking for 840 hp.

I like Whipple over Procharger, I've had both.

To let a reputable engine shop build for you expect to pay around 25k +for everything.

To do yourself around 15k

Those are rough prices but will give you an idea.

Niceguy covered the rest.

RBeyer 06-08-2009 05:01 PM


Originally Posted by niceguy (Post 2883105)
With fuel injection your choices are only limited by your budget, but to get 840hp out of a stock 502 by simply adding a blower? Ummm, I disagree... unless you are gonna run race gas and even then, I dunno?

Anyways, the cheapest route is going to be a procharger system.

Second is the whipple, but more expensive.

And finally you can always go the roots blower style with custom throttle bodies and aftermarket FI system.

Keep a few things in mind here before you buy any parts: you will always have to upgrade existing systems to make more power. Fuel system is number one, in your case the ecm is number two... a good tune is the key to power and longevity. Three is gonna be oil cooling system, and four is gonna be exhaust.

Now that your making tons of power, the drives are next. If you have B1's like I do.... I think they are only rated for like 550hp. So with the torque of the supercharger, either be prepared to be easy on the sticks or you'll be doing drivews immediately after you finish making tons of power. But what drives to go with? That, I cannot tell you... but I would like to know myself.

This is my two cents.

Totally agree. I have a ProCharged and modified 454 now 468. Injectors, ECM, exhaust, aluminum heads, and I gave up on Bravo1 now run a B-Max. That is alot of HP for 502 I am at 720 at 7lbs and alot of modification good luck. You are limited by your budget only.

ZXXX Donzi 06-08-2009 07:14 PM


Originally Posted by Pure Energy (Post 2883376)
He never said he was looking for 840 hp.

I like Whipple over Procharger, I've had both.

To let a reputable engine shop build for you expect to pay around 25k +for everything.

To do yourself around 15k

Those are rough prices but will give you an idea.

Niceguy covered the rest.

I never said he said he wanted 840. I was addressing that 840hp claim from Superwhatever USA. The one with the exclamation point next to it!

My point being is that there is more to it than slapping on a blower if you want the power that they claim.

I can't compare whipple vs Procharger on a personal basis. I have a Procharged boat and have been in a number of whipple boats.

I do have a Procharged engine that makes 942hp so I know a little about that. And I still have the 502 EFI setup although it has been modified good bit.

kennyo 06-09-2009 07:56 AM

You better start budgeting $5K a year after you do this to replace/repair all the shlt you're going to tear up. Everyone who posted knows what I'm talking about. I spent $2400 to go boating this weekend. That boat is huge, I would leave it alone and look good and be dependable.

hoozeyurdaddy 06-09-2009 08:21 AM

I think everyone has made it pretty clear, don't believe what you read on some of these web sites, there is always something else to it, and be prepared to spend a lot of money, and I mean alot, if you want more ponies, look in the classified's for a pair of engines already built by a good know builder and spend the bucks, sell off your stock 502's to help soften the blow.


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