I agree the hp numbers were under-rated. Keep in mind tho that these cars make alot of torque. The factory rated them at 360ft/lbs I think. Thats about what todays pickup trucks makes (unless you have a Lightning headbang or a diesel). I do recall one of our members saying that their stock GN dyno'd at 450ft/lbs peak torque eek! (maybe it had a Lightning motor in it headbang ). GM wasn't to pleased with having their Corvette belittled by anything in any catagory (except towing) so these cars were under-rated. But even tho these cars were weaker than the Corvette a Stock GNX beat the Twin Turbo'd Calloway Vette in the 1/4 mile yup . Just think if they had as much power as the Vette ..... wink .