Some of the fastest racing in the world (where the competitors are still stuck to the ground for most of the time) is that of the MotoGP 500cc circuit. 200mph. Raw. A lot more raw than stock car or F1 or anything with a cage around it. More intense than a foot race or a bicycle race or even a lawnmower race (though I commend the lawnmower racers).
Check out the documentary that'll tell you all about it:
Faster.