I am running a Dayco 79.5 inch belt with a 2.93/4lb with the billetflow idlers with stock alt. pulley. I don't know if they make the alt pulleys a different size though. My idler pulley is on the middle hole of the bracket also. This makes a big difference in belt size. I know of people running the Gates # 79.7 length belt with this set-up also.