The OP mentioned he had a standard 502 in the first post. Only issue (since he has not been back) as I see it is if he has less then a 415HP engine, that is unless standard means something else then I think it does

The FAST ez efi system is a major upgrade from a carb. I put one on my 496 stroker build and couldn't be any happier. No fuss setup, the default maps are close, and it hones in to perfect very quick. It even tolerates my cam and doesn't load up during those long idles out of those endless no wake areas.

My bad, another member mentioned it.

If you are speaking to my post, notice I said "up to 600hp". The holley Terminator throttle body style would be perfect for a 415 hp 502, or he could do the FAST stystem with throttle body injection.

No, I was responding to BUP post mention about what HP the OP had (Superman09). Being stock it would be either 415 or less as I looked at it.

Reading this thread I'm going to look closer at the FAST or Holley system may be a better then fixing my current running rich VST 502 engine.

Mercruiser stock OEM black 502 MAG MPI is 415 hp and the older carb version was 385 hp. / 1990's apps

454 MAG MPI is 385 hp and the carb version HO MAG was 350 hp / 1990's apps

Gotcha. Yeah the Holley or FAST would obviously be a much better system( I just purchased a Holley HP MPFI kit a few months back). Have several friends who have converted and love it. Just don't expect it's always going to offer more power. The greater gains lye in idle quality, built in safeguards, individual cylinder timing( sequential) tune ability/adaptability to elevation(02 installed) throttle response....... And the list goes on. It's expensive, but then again, so is a new engine. Good luck!

Okay let's relive this. I missed the updates here and have simply been enjoying the boat!

Spec's I should have included:

502ci gone through becoming 505ci.
Dart 310cc ported heads,
Merlin Intake Manifold,
MSD ignition,
Crane #268761 230/352-2s-14-IG cam
Quick Fuel Carb

Made 610hp 613tq on the engine dyno.

Want to convert to EFI for a Forced Induction application. No desire at all to do the blow-thru carb stuff and have a plethora of good tuners around for the EFI.

Looking to add 5-6 psi of boost to it.

Based on that what would you recommend for an EFI set-up? I found this on the forum and also what the guy posted on the first page as well: http://www.offshoreonly.com/forums/s...-up-502-a.html

Look at this..
http://www.racingjunk.com/Intake-Man...IRING-ETC.html

Thanks, however looking for something with a factory style intake and TB!