if you bought the 36972k Tecumseh billet rod it's for a Motorsports crank with a 1" journal, you'll have to turn your journal down and then find bearings for it if it didn't come with them.. If you had an H70 you can use a Tec Star rod with some clearancing of the block..I'm building an h70 now with a mild ground cam, hm80 lifters (longer), Star springs, hm80 carb etc.