How about a 433? i remember mine with the stock carbs and clutching would run up to 8600,now i have 75 heads and cylinders mildly cleaned up with the combustion chamber mod ,40 over wiesco's,hewtech cdi and a set of 38 mm mik's.i'm thinking it should be in the 8400 to 8600 rpm? it will be run on the ovals in the superstock class