The only car that I think might have the staying power would be a Lotus Espirit. Don't get me wrong I love the NSX ( and have one ) but an 8 cyl non-turbo lotus would probably have a field day. The same might be said for a couple of Porsches (928 s4 comes to mind).
This had been tried but not for the lenth of time you are speaking, on a track in Wisc. A Ferrari, An NSX a Porsche, and 2 racing lotus' (that were set up for this track).
The Ferrari overheated his brakes and was out until they changed the fluid, The NSX stayed with the Lotus' but the Porsche lost a lap.
At the end of just 25 laps the NSX was 3rd behind the two Lotus', The Porsche was back a lap and the Ferrari was out. So, was it luck, the drivers or the cars?