vette427-sbc
05-22-2012, 05:12 PM
Im having a seriously difficult time finishing the engine build for my fathers '55 chevy...
Background:
Bought a Dart SHP block, forged internals, flat tops, etc... 4.155 bore The heads are standard off the shelf AFR 195's with the 75cc chamber. The drawback of the shortblock that we have is that the pistons are .025 in the hole (got a good deal on it). With the 75cc head, we are trying to get a reasonable compression ratio and quench with a thin gasket.
First gasket set- ECS steel shim. .015 compressed. Perfect for quench and compression. Problem- hung into the combustion chamber too much.
Second gasket set- Custom Cometic. 4.185 bore .027 compressed. STILL hangs into the combustion chamber near the valves.
THIRD gasket set- Custom Cometics again. 4.200 bore, .020 compressed with a bump out for the valves. I can still catch my fingernail on the gasket near the valves.
What gaskets are people using on these AFR heads??? Or do they not check the gasket fit before using them? The recommended Fel Pro gasket is way to thick to use in this application. I assume it is not OK to have the gasket hang into the combustion chamber?
Background:
Bought a Dart SHP block, forged internals, flat tops, etc... 4.155 bore The heads are standard off the shelf AFR 195's with the 75cc chamber. The drawback of the shortblock that we have is that the pistons are .025 in the hole (got a good deal on it). With the 75cc head, we are trying to get a reasonable compression ratio and quench with a thin gasket.
First gasket set- ECS steel shim. .015 compressed. Perfect for quench and compression. Problem- hung into the combustion chamber too much.
Second gasket set- Custom Cometic. 4.185 bore .027 compressed. STILL hangs into the combustion chamber near the valves.
THIRD gasket set- Custom Cometics again. 4.200 bore, .020 compressed with a bump out for the valves. I can still catch my fingernail on the gasket near the valves.
What gaskets are people using on these AFR heads??? Or do they not check the gasket fit before using them? The recommended Fel Pro gasket is way to thick to use in this application. I assume it is not OK to have the gasket hang into the combustion chamber?