i have a 94502mag,efi.i belive the h/p rating is 415.toying w/putting decent,double plane intake on it and a 800-850 holly double pumper on the engine and keeping the same heads and cam.how do you thank the engine will perform....more or less h/p,and how reliable,fuel consumption.the boat is a 27fever,1994.thanks.

You definately won't gain anything and will probably increase fuel consumption.

If I had that engine, I'd bolt on a set of AFR 305 heads, a new slightly larger cam to make peak power at 5,500rpm, a Edelbrock RPM Air-Gap intake and a 850 cfm carb. Then upgrade exhaust to some 496HO take-offs. Total upgrade $3000. Should be good for 550hp.

Put a crane 731 cam and headers remap the ecu and leave it the hell alone.

Air gap dual plane is nice.

What parts are you stealing to come up with 3K????

More like 5k by the time you are done and you can't run a lot of cam with the 496 exhaust.

$2000 for heads (JEGS)
$300 for exhaust (same as I paid for mine)
$250 for intake
$200 for cam
$250 (maybe more) for carb (ebay or swap meet)

I don't steal, I shop!

WHY would you want to get rid of the efi? That's crazy unless you just like working on sh*t all the time.

I don't think it has a hdy roller cam on the 94 so thats some big bucks to change, I spent 6000 on my 1st upgrade in 95 on my 93 502. to get 585 hp and 580tq switch to hdy roller cam, 1500, head work 700, dart intake 400,bg carb 850 700,exh dry 2700, flame ar 200,msd full 1000 so over $7200 plus labor latest rebuild to a 509 9.5 to 1 added merlin heads isky cam nickerson 1050 dom, dart intake which netted me 650 hp with a stock 1050 so with the nickerson they fell another 20hp so 670hp and over 640tq.that work was another 7200. art

because i have alot of engine stuff left over from my drag-racing days,plus a carberated motor would be easy and cheap to fix,trouble shoot,etc.parts this i have ,efi i do not.do not get me wrong,efi is better as far as fuel consumption goes,but parts cost more and you have to go to mercury to get them....some of them.besides,dont carberated motors make more h/p?thanks for all the input.