I have installed many of these on customer cars, used a couple myself on my own cars, and keep up on what others are doing. The figures above should give you a good idea to shoot for, if your looking to max this turbocharger out. But like I mentioned, typically on most 2 and even 4V's, the T70 makes peak power around 20psi... Sure you can push it past that, but lets remember boost is just a number. I run mine around 18psi daily, and so far I've ran 130mph in the 1/4 and 102mph in the 1/8 on a real mild 2v 4r70w Saleen. With the .68 housing I had on the car, 18psi was the max, as backpressure became an issue.