I was told by a bike racer that the shell optimax is a denser fuel :wand it doesnt go in single cylinder engines! But what the hell we got eight cylinders , I said! well it suppose to be the better to clean out fuel systems,but I dont know,I put it in my mustang with a bottle of booster and the little 289 done a 15.2 quater mile ! thats good enough for me;+