I was looking at the Cometic multilayered steel head gaskets, and I see they have many different thicknesses. My guess would be the thinner the higher the compression, and the thicker the lower it would be, is that the case or no?

Correct. .040 is stock I believe.



"In Oldskool we trust"

So with running boost, I would want the thickest gasket they make for the eco, which is 0.080". Now my next question, is there a way to get a good idea of what the CR would be?(a little math equation) I know the stock ratio is 10-1, so adding a gasket that is twice the size would have to make a decent difference.

What kind of boost are we talking about? If you're supercharged with an m62 I'd strongly suggest stock thickness or maybe even thinner. That setup really loves the extra compression. Even with a lower boost turbo setup I'd try to bump the compression a little. It won't hurt anything if it's tuned right and you'll really appreciate the results. No one wants a motor that's a dog until 4000rpm and 15+psi.



"In Oldskool we trust"

Well, in a few days I will swapping over to a bored out M62 and running a 2.7" pulley. So I figured the lower compression would help keep the bottom end safer, and less of a chance of knocking. Yall are the ones with the experience though, you say go for it, I will trust your judgement.