lower compression ratio?

I apologize in advance if this question has already been answered, I couldn't find it. I saw the Hahn turbo kit for the N/A GS and it said that the boost is 8. How can I lower my compression ratio so that I can run a higher boost? My 420A engine has a 9.5 ratio and I am hoping to get it closer to 8.5. A friend told me that is a good number to run a lot of boost. Or is this all just one bad idea? Thanks guys.

You need to rebuild with lower comp pistons.

If you need more power than a basic Hahn kit, you are looking into an engine rebuild, where you can make lower compression happen. Consider the cost of buying a turbo DSM before spending $5000 on a non-turbo, also.