I found a set of pistons I want to use in my new engine, but the only problem is that they only have a 8.9:1 compression ratio. I really want o be up @9.5-9.6:1 to help spool my turbo a bit faster and to not feel sluggish off boost. My question is if it is possible ot raise the compresion up to the range I want by maching the head. I know it may sound like a dumb question, but I am new to building engines for turbo, so any help would be appreciated.

 

I would not recommend having your head milled or block decked just to come up to your needed compression. You are basically just taking life away from both parts by doing that. Plus, the money spent on having machine work done could have been money spent on the proper set of pistons.
Do yourself a favor and spend the money on pistons that have the compression ratio you are looking for.
A thinner headgasket will drop compression a bit, but then you may have sealing issues. You could have the head cloverleafed, but that more for N/A applications and will cost you $$ to have that done.