Originally Posted by phunk

really old thread... these days 600+ is rather common. I ended up taking mine to 671. We have another car here that made 701. Lots of my customers are in the 600s.

I would never promise anyone that 600+ will be reliable. But it turns out, it tends to be. But you really need to watch your torque... and try and ramp in the boost so you can make your HP numbers without having to bring the torque up too high.