It made 568rwhp on the dyno at 5800RPM but it got into valve float at that point. It was on a very steady climb before that. He has since up'd the spring pressure, gone with a different rocker arm, the new Comp Cams short travel lifters, and got stiffer pushrods. This has eliminated the problem. I expect it to make some where in the 580-600rwhp range but that is only an educated guess. It could be less it could be more. He should be getting it back on the dyno somtime soon. So far it has killed my Cobra, an HCI LS2 GTO, and a stock C6Z06. So it is making some pretty decent power.