A friend of mine has a Corvette ZR6, I forget which year maybe a 2003 or 2004, and it didn't have enough power even after he'd tweaked it up to about 550 dyno'd horsepower.
So, he's had this 440 cubic inch monster installed. Dyno'd at 647 horsepower and 608 ftlb's of torque. Should satisfy him, for a while.
He's tracked the car at Leguna Seca, and maybe Sears Point, with his local club.