[undy]

The accepted drivetrain loss for the new Z06 is 11.5%, +/-. That would support what Keith said. My headers/intake/tune C6 Z06 puts down 494 rwhp, SAE. Factoring in the 11.5% that would equate to 558 hp. I recently redyno'd it and at a 74 deg day it put down 509 rwhp, standard not corrected.

BTW ... It not just the difference between Gross and SAE corrected ratings. There's a new accepted rating on the block which tends to under-rate "conventional" HP ratings. It's the new SAE-J rating. Most OEMs have now switched to it now.

I'd hazard a guess that a totally stock 505hp LS7 crate motor would achieve 550+ corrected engine dyno HP on most of our board vendors' engine dynos.