You are forgetting that skidpad Gs and Gs that are actually generated at the track is completely different. Watch the video of the GT500s record run at VIR and you can see that the Gs sometimes reach 1.2 and are, in most corners, above 1.0g. Also, pay close attention to the speed at which those Gs are at. The current ZL1 will likely pull Gs closer to what the GT500 and CTS-V does in real track duty (1.1-1.3g+)