Why thicker head gaskets?

[Jeff240sx]

Won't thicker head gaskets reduce compression in turbo charged engines? Of course... but why would you want that?
Now theoretically, if you have an engine that can handle it, you'd make more power with less boost and higher compression, right?
So why would you get a thicker gasket just to lower compression and turn up boost? Is it just to say you are running massive psi?

And this all brings into account another question I had. How is the compression ratio accounted for? It would be like 10.5:1 what? Is it using stoichiometric 14.7 psi atmosphere pressure? So it would be 10.5psi compression per each psi of the 14.7 psi atmospheric pressure? That would make 154.35 psi in the cylinder. And then boosting, such as 10 psi... what does that add on to? Does that make it 24.7psi in the cylinder before the 10.5 compression slugs hit it?

I guess I just wanna know the really technical stuff about turbo apps, and if you could just point me to a site that would answer my questions... that'd be great!
Thanks,
-Jeff

[ca18guy]

I think the benifits of the added boost negate the effects of a lower compression ratio. Compression ratio and Compression are different. Here is a formula for compression -> Compression = (Compression Ratio minus one) to the 1.1 to 1.2 power multiplied by Atmospheric Pressure (14.7) notice I said a formula, there are countless formula regarding compression and compression ratio. Think of Compression Ratio as the space you have when the pistion is at top dead center, If you lower the compression you can cram more air and fuel in there for more power (I know thats not the right answer but is the best way to think of it in turbocharging terms) anyway before I go deeper in to something I'm not sure about let me point you to a sight that would know. Goto the banter&chat forum at www.zcar.com and post this post there they will answer it alot better then I could.