Way back when, at a PCA track event, a member showed up with a semi including a 40' trailer filled with cars. After stuffing his 911 badly, he casually rolled out an NSX, and proceeded to put down many of the faster laps of the day. The completely stock NSX looked slow compared to the tail-wagging turbos and scrabbling-for-traction C4s, but the lap times showed it was stupidly quick.
Whether from the pits or through my windscreen, I'd never seen a road car going that fast on the track looking so calm and controlled.