I'm builging a 355 with -5cc pistons, the block has been zero decked, I'm using felpro .039 head gaskets, and the heads cc'd at 48. I'm using a Joe O cam simular to the GM 847. I know it's going to be pretty high, but I can't figure it out. Thanks

 

Here is the static compression. I came up with 12.84 if those are flat top pistons with the 5cc valve reliefs. If they are slightly domed then I came up with 15.15. I used 4.090 for the inside diameter of the head gasket. It won't change things much if I'm off a little. Are you sure about the 48cc head volume?

 

I had a local machine shop cc the heads, I don't know what method they used but he told me they were 48 cc, I thought that was a little low myself. Is it possible for an LT1 head to have that low of a cc in the combustion chamber? The heads came off os Saintx's 383 that came from nitro Dave. They were ported by MTI.

 

If you had a 58 cc head, which I believe is the original volume that would put you at a more realistic compression of 11.2. It is possible that they F---ed up ccing the head.