thicker metal head gaskets
 

does anyone do one for the s12?

Fl EBAY.com or .com.au

Why do you want a thicker head gasket? What are you trying to achieve?

thicker gasket so can run more boost and will be stronger

The CA18ET is already 8:1.

It don't need to be any lower unless you want ridiculous boost.

i ran 32psi with the stock gasket.

Thicker gasket would upset the cam timing and also harm off boost performance and fuel economy imho

The cam would be advanced by less than a degree with even a 2mm gasket, so its not anything significant.

The off boost power would be reduced.

All of the above plus the fact that the boost depends on a fine balance between the comprssion ratio and the volume of air been induced into the cylinders. Yes the engine will take in more air, but what you gain you'll lose automatically becase the compression ratio will be far less. Sorry mate but you'll acheive nothing.