I bet you most of the people who own Zs and want to TT or SC them have never ever reached the limits of their cars on a track. Its like some stupid wet dream you have... oohhh I wanna TT it so i can go FAST! Let me tell you this -driving on a track is wayy more fun when you and the car and communicating. What I have found is normally - FI'd cars tend to have a non linear TQ delivery causing some very funny moments mid corner. It will take you 10 times more seat time to get warm and comfy with a TT'd 370 on a track as compared to an NA one. When I was at infineon, the Z could not have been more predictable through the corners - something I am not willing to compromise for a second in the quarter and more passing power on the freeway. My 2c tho