Like I say, I`m not the best to ask, Nigel, knowing so little about NASCAR. I`ll leave aside all the possible problems with load on ovals - is that the spectre of Michelingate I see before me? The top speed of an F1 car is over 300kph but the average lap is considerably less. Fiorano is about 180-190 kph. So I`m not sure F1 cars would be able to reach anything like the speed you imagine on an oval ..... but there`s bound to others here who will be able to answer with more certainty & more knowledge.