What heads???

[jbone]

Can anyone tell me how these heads perform and if I should consider replacing them to increase hp on my carberated 502 (415 hp).
The heads are stamped with a GM number. The number is 12562934.
Thanks

[Gearhead]

12562934...00-up...rect...OPEN...Gen.VI 502 Marine 14011077
These cylinder heads should be a good baseline for your combination. A minor port job (bowl work, combustion chamber and port match) will improve the flow, torque and horsepower. A camshaft change may help too. Just rememeber to match parts for the realistic RPM that your engine will turn the impellar/hull combination.

[jbone]

Thanks for the numbers.
Do you know what the volume of the combustion chambers are?
J

[Gearhead]

I believe they should be around 118 cc.

[lucky]

ohh, pardon me - I was mistaken when i read this thread , I though someone found a copy of my marriage vowes

[jbone]

That's a good one. Funny, but true. :cry: