Okay, I found this: http://www.rbracing-rsr.com/compstaticcalc.html but didn't really know a couple of the things (i.e. deck height and piston top volume - a couple things I could measure a little later on, but I wanna know NOW, haha).

Anyways I wanted to know the difference between how the engine I'm working on is set up now, and how it will be after a change of heads.

It's a 355 with flat top pistons. Right now it has a set of 305 heads (58 cc). I guessed it would be upper 10s to 11:1 CR.

I bought a set of 882s (76 cc) from CamaroMan79 and was guessing around upper 8s to low 9:1 CR. Sound about right?

(I can also give you some more specs if some of you more knowledgeable engine guys want to give me a horsepower/torque estimate http://www.nastyz28.com/ubb/smile.gif)

Most standard rebuild 355's have a deck height of .025(or close to it)& a typical 4 valve relief flattop piston is 5cc's.
With .040 head gaskets, that gives you 10.49:1 with the 58cc heads & 8.69:1 with the 76cc heads.

Woo! Thanks gregh!