I have a question.... about compression ratio. My engine that i have in the garage has about 8.5:1 compression with 70cc heads, what kind of compression should i be getting if i swap to 64cc heads.

 

Chevy didn't make many 70cc heads. If this is a 350ci engine with that rated compression ratio it's probably got 76cc heads on it.

Anyways, if you swap on some 64cc heads along with a typical Fel Pro .039" rebuilder head gasket you'll be at about 9.1:1. If you use a slightly thinner GMPP .028" head gasket you'll be at about 9.3:1

 

Thanks for the help... im fixin' to go outside to put the exhaust back on my car because i took it off to fix my torque arm mount.. i'll get the casting numbers off my engine in my garage and double check, but thanks.