i built this 350 with used but good parts from my buddies 94 full size chevy, stock crank rods and pistons, and used a felpro gasket that i got from summit in the seal kit, and i have 64 cc camel hump heads, so whats my cr ? the deck height would be 0.025 since the block was not decked correct? what would the value be for my pistons? also the head gasket value? i think stock that motor was 9.5 to one right? so i should be like 10.2:1 correct?

 

Stock flat-top pistons with 4 valve reliefs = 6cc

Replacement head gasket = look at the gasket specs, it will tell you the compressed thickness, which is what you want to know. Typical 'rebuilder' gasket is .039-.041 thickness and around 4.1" gasket bore (I can't remember the exact figure for that).

Deck = .025" is about right if you are using the orignal pistons and an undecked block.

OK.... if we assume you used stock-type pistons, 64cc heads, std deck height and clearance, 3.48 (350ci) stroke, std 4.0" bore, and the generic .039 head gasket you have... lessseee..... 9.578:1 compression ratio.

http://kb-silvolite.com/calc.php?action=comp

 

Stock flat top pistons in a 350? From a 94 chev truck? I would have guessed a 350 from a '94 chev truck (or did you mean full size, as in caprice?) would be 12cc dish?

 

yea i looked for that spec on the gasket, and i couldn't find it anywhere, also i read somewhere for a stock piston it was about 4.5 for the valve reliefs?? i think it was a permatorque gasket, not sure tho

 

Permatorque should be .039" thickness IIRC. My calculation still stands.

4.5cc is on the low side for a set of 4-valve releif pistons. They are typically 6-7cc.