.....Probably close to 50 years ago now, there was a late model series that ran Anderson Speedway, Home of the "Little 500" Sprint car race, and a track near New Castle IN called MT Lawn, that ran 6 cylinders and called the series "Super Six", not sure what modifications were allowed to the motors, most were 292, Chevys and Jimmys, I suppose the Fords could be used and perhaps even smaller CI displacement, I don't know. Regardless the car count was awesome and the racing just as good, Fun stuff.