What you would want, if you're staying w/ stock Crank & SC pulley, is the PSKC3. It is made for the addition of a smaller SC pulley, but works fine for a stock setup. The tensioner will accommodate the minor difference in the diameter between the stock SC pulley and a smaller SC pulley. Please double check w/ Rob @ Needswings w/ this info., as there may be a slightly larger belt than the #1153 that comes w/ the PSKC3 that may be more ideal, but I don't think so. You'll be all set if you decide to get a smaller SC pulley for more power in the future.