I am looking for the formula to calculate CR. what will the ball park compression be with a pair of 58cc heads on a stock 350 block.

Here is a formula out of a book I have.

CR=C-(P) + G + V / C-(P) + G

C= combustion chamber volume
P= displaced dome volume
G= compressed head gasket volume
V= swept volume in the cylinder

I don't know if you will find this helpful, but there it is...

When I figured my compression ratio on my latest engine, it took me a while to figure it all out. I don't estimate, I measure the volumes and get an exact answer...

do a google search, "compression calculator" and youll get a buch of sites where you can just punch in a bunch of your numbers and it will calculate it for you.....yeah im lazy....

Here is one I got from "vader" ....

http://216.121.161.76/files/EngineCalculator.xls

About 10.2, give or take.