Flat Top Pistons

KB has these https://www.uempistons.com/index.ph...d=2999&zenid=f39c5f4f358b2819fd2ddb0c50a19287 that will get you in the 11:1 range. If that isn't enough KB 191s will get you into the 13:1 range. Plan on a rebore and rebalancing with either set though...