"It always happens this way. Shortly after a new performance car is released to the public, it will find its way to a dyno shortly thereafter. When that new vehicle is the new performance king of the automotive world, aka the 2009 Corvette ZR1, our collective interest is piqued. So, how does it fare on the rollers? Two separate 'Vettes were tested, and the average output was about 535 horsepower at the rear wheels. After factoring in the normal 15-percent drivetrain losses for a rear-wheel drive car, that's pretty darn close to the claimed 638. After a bit of tinkering the team got that number up near 570, saying it's running a bit rich from the factory. Click here for the full graph.
Until the V-Spec GT-R is unveiled the ZR1's most natural competitor might be the normal Nissan GT-R; despite the pricing disparity between the two, they are the two most amazing performance bargains currently on the market. For what it's worth, the GT-R seems to be averaging about 420 horsepower at the wheels. Apples to oranges? Sure, but it's always fun to throw a little more fuel on the fire. If we didn't do it, you know it would come up in the comments. And so it will, have fun."
WOW! A little tune to lean her up a bit and another nearly 40 horse'! Just wait 'til people start bolt-on tinkering!!!