Who ever told you 8psi is a lie. There are 600hp stock blocks and people beat on them but that goes down to tune! Which K20 do you have? z3,a2,a3?? I went with a BoostJunkyz turbo kit check them out at www.boostjunkyz.com also mywhitesi or whatever his username on here are running this kit! I build a block I build that should hold up find to 600+ easily but the K series transmission will start to fail at 400tq.