I am trying to guess my compression ratio. Im not looking for precise data, just ballpark figures.
I have a .040 over 350 with flat-top pistions with 4 valve reliefs.
Old-school '882 heads with 72 or 74cc chambers,,cant remember.
And blue head gaskets,,, I think they said permatorq, or something like that.
They are composition type.
What do ya think,,maybe low 9's compression or so? or is it like 8.5:1
Anyone care to have a guess?
Thank you
The heads have been "surfaced"; but no extra material has been removed.
Block has NOT been decked. Just an old stock high-mile engine block.
I just had it bored and bought some cast flat-top pistons, stock style.

 

Without all the relevent info
8.9:1 assuming 72cc heads, 0.040 head gasket and 6 cc valve reliefs
If any of these specs are larger CR ( thicker head gasket, etc ) CR will be lower

 

Thank you