I have a 35 Fountain with 2000 HP 500EFI motors with whipple chargers. one engine just detonated cyl # 7 so that there was nothing left of the spark plug. Upon removing the head I found the intake valve starting to tulip and it shows signs of extremme heat on the edge next to the exhaust valve. The remaining plugs look ok with only minimal signs of detonation. A few of the other intake valves do show small signs of getting hot. The other engine in the boat is fine. What could be causing this to happen on only one engine ? Fuel pressure on both motors if 57-60PSI at full throttle. Any help is appreciated

Wow! 2000HP out of a 500EFI! Thats increadible. Any way you know the basics, detonation, extreme heat means a lean condition. Now to find out what is causing it. Fuel pressure seems good so look at everything else in the fuel system. Sorry this did not help much.

ps 2000 HP has got to be a typo right? Did you mean year 2000 HP500EFI?

Ron

Yes I ment year 2000 HP 500EFI. I could only wish it was 2000HP

I am not an expert on superchargers. But from what I know about motors in general, you have alean condition in that cylinder. Since your fuel ressure is good, there could possibly be a is a lean condition due to either a faulty injector or a badly re-mapped e.c.u.

Have you checked your block water pressure? I would check if you haven't.

How many hours did you have on the whipple setup? I have heard of this exact problem with another 35 lightning. What is your water pressure at part throttle and at WOT? Best to contact Dustin to look for causes. Good luck.

I would call Bruce Wolffe at (616) 422-1090. He has been re-mapping chips and using a different Injector for those set ups. Number 2 and number 7 are usually the ones to go. I had one valve you could of used as a tee once. Give him a call and he should be able to help with the issues.

I agree with Sgrady, Wolff is an excellent trouble shooter and has repaired/corrected several Whipple systems as well as Pro Chargers and Roots style systems. His shop is pretty much geared for marine applications and he can usually correct a lot of complicated stuff.

The engine had about 5 hrs on it after a rebuild. It had two damaged valve seats the first time, most likely caused by a leaking CMI header both 5 & 7. The other engine has about 35 hrs on the whipple setup with no problems. The block pressure is 35+ pounds at WOT and 25-30 at cruise. I don't think block pressure is the issue. Maybe bad wires causing cyl 7 to fire early ?

For whatever reason the number two and number 7 seem to always be the isse with the 502 blocks, seems to be a Water jacket and Manifold issue with them. I am not sure what changes you made or came with the kit that was installed, but I know that I had issues with a Procharger set up and had a friend that had one with the whipple.

I know that Bruse had switched to Ford injectors on the Fountain with the whipple and that semed to solve that issue.

Did the Head Gasket let go ? What kind of gaskets did you use ?

My ..02 but I would give Bruce a call or someone who has worked with "Changing" these kits, do not become R&D for someone else. I did for a while, I ended up going to him and never had the issue again.

Just my .02, good luck and be safe.