502 Engine Upgrade
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I have a 35' 2001 Fountain Classic (single step). I have upgraded the 502's with a little help from Arizona Speed with the following: CMI e-tops, msd iginition, k&n filters, Dart Pro One aluminum heads, extruded the intake manifold, a more agressive cam.
I only increased my top speed about 3 mph. I am turning about 5,200 wot w/ 26 intimidators. Since I am not happy with this minimal increase, I am looking at either increasing my 502's to 540's or adding a supercharger to my existing set-up. I have spoken to Arizona Speed about this application and Jim says that I could get about 620 na or 700 going the supercharging route.
What are your suggestions? Should I be looking at other engine builders? What expectations should I have about speed increases?
I only increased my top speed about 3 mph. I am turning about 5,200 wot w/ 26 intimidators. Since I am not happy with this minimal increase, I am looking at either increasing my 502's to 540's or adding a supercharger to my existing set-up. I have spoken to Arizona Speed about this application and Jim says that I could get about 620 na or 700 going the supercharging route.
What are your suggestions? Should I be looking at other engine builders? What expectations should I have about speed increases?
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You could get alot of HP from port work on your heads,ballancing your internals, degreeing your cam and some carb work. What are the specs of the engines. Compression,heads,intake ect ? We have gotten as much as 750hp from aspirated 502 already with those mods which leave you a less tempermental and more reliable engine. If you would like to know more give me a call or email me.
Thx Mike
[email protected]
570-956-2840
www.roccardmarineengines.com
Thx Mike
[email protected]
570-956-2840
www.roccardmarineengines.com
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We need a little more info on cylinder heads and cam in order to have realistic comments on your existing setup, but something does not seem right.
3 mph = 60 hp over your original 502's.....hmmm...same hp as an HP 500 EFI, but at considerable expense (aluminum heads) over just putting larger intake valves in your stock heads. The msd and k&n provide no measurable performance gains, so the what that leaves you with is the CMI's - definately required - Aluminum heads - should be considerably better than stock 500 heads, but need info on cam to determine their compatibility. I'm guessing there is a little more to be had in your setup. If all components are working together you should be in the 540/550 hp range which should put you realistically 5-7 mph faster than stock 502's
And that's my $.02.
3 mph = 60 hp over your original 502's.....hmmm...same hp as an HP 500 EFI, but at considerable expense (aluminum heads) over just putting larger intake valves in your stock heads. The msd and k&n provide no measurable performance gains, so the what that leaves you with is the CMI's - definately required - Aluminum heads - should be considerably better than stock 500 heads, but need info on cam to determine their compatibility. I'm guessing there is a little more to be had in your setup. If all components are working together you should be in the 540/550 hp range which should put you realistically 5-7 mph faster than stock 502's
And that's my $.02.
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Originally Posted by mike11
We have gotten as much as 750hp from aspirated 502 already with those mods which leave you a less tempermental and more reliable engine. [email protected]
570-956-2840
www.roccardmarineengines.com
570-956-2840
www.roccardmarineengines.com
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I would have to question anyone who says they can get 750 hp out of a n/a 502 and still have decent drivability. 750-800 hp is super cat type power and we know how drivable they are at low speeds.
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We are doing one right now and are expecting around 800 with a tall deck,10.5 to one comp pump gas. 9.5 comp and some head, carb work and a cam change you should see 650-700.
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I can tell you you can make 750 or 800 hp out of 509 ci but I can't see how it could be done with a conventional type head and low comp I think if you really want to pick up the performance of your Fountain you can go with a larger ci engine that will make more power and torque with unquestionably more reliability . We build marine packages from 500 -1000 hp with a 12 month warranty and also racing engine programs available. Good luck Laz Mesa www.mesabalancing.com