Later I was planning upgrading to a roots Gary Dyer's 671 @12 psi but it will be the last thing I do after all else is done. The T&D either in race or street is pricey but sure looks bullet proof. Eventually I would like to be getting 700-800 but not sure what my current combo with tuning will produce. I am going to take it somewhere and have it tuned on a chassis dyno when I am done but I think 600 is a conservative number. I spent a lot more in research so far than actually working on the car. Especially in the engine area but none I talk to will quote any numbers so actually I might be in for a a supprise or terrible let down, hopefully not the latter.