I don't really want to waste my money on bolt ons right now as what I have on now is good enough for the power my car is putting out. I want to either build the head or put in some higher compression pistons. I've been told that using high compression pisons without first preparing the head can damage it from the extra stress the motor wasn't designed for. I'm not sure exactly what size piston I'm looking at yet because I'm going to go FI within a year or so and I don't want to push it too far. My goal is to have the car run 13 second 1/4's daily driven with not more than 8psi on the turbo. I'm not sure how much hp that's going to take I don't have very easy access to a dyno I measure all my gains in terms of 1/4 mile time. So any info as to whether the head work or slugs will get me more power, if I should be building the head first regardless, and what size/stage I should be looking at for the numbers I want to produce would be appreciated. I should probably add that it's a 98 GSR 2 Door.