i have an '05 GTO with catback/K&N intake, and have taken down one mach1 and a mild bolt-on '99ish cobra, and several '05+ GT's. the mach1 was when i was stock, and it was a 30 roll. the GTO feels a bit weaker than my '04 cobra did stock, but not by much. these cars are hard to launch (just like terminators), but once you get rolling, they squat and go. i'd be amazed if a stock mach1 could take an LS2 GTO from a roll with equal drivers. from a dig, who knows, the mach will most likely pull a bit at first, but will still get passed, and passed hard above 100mph.