Some years ago I drove my friends mothers Capri round the Nordschlief. We were on a camping holiday. All I can say is that it's a good job the Capri was easy to handle when sideways. A fast right is followed immediately by a sharp left just over a brow - you get the idea. By the end of the lap, all the camping pots and pans were dinted as was the side bodywork of the car, from the inside out!
I don't think I'd like to take my GT40 round, too much chance of damage, not only to the bodywork when I ran out of track (Note - I said when not if!), but also to the underside on all the changes of camber, bumps, yumps etc. If it was raining, I doubt very much if I'd get to the end of the lap, what hero's the race guys were!
One more point, keep your eye half on the rear view mirror. It doesn't matter how fast you think you are going, some race test driver in the latest machinery will be going twice as fast.
Regards
Dave Tickle