Thinking about swapping out the GT500 for a 2016-17 C7Z with the A8. I feel like I've reached the point of diminished returns on mods for the GT500 unless I want to spend big bucks to pull and build the engine and the M6 just can't compete with the new auto cars. I have the Porsche for fun cruising in a sick car that used to be top dog on the streets. The 930 easily beats the GT500 in that department. As far as Vettes... I know next to nothing about them. Cooling issues seem like a non issue for street and drag. Head issues seem to be easily dealt with with the basic mods anyway.