The OEM's put in the correct parts to survive supercharged applications. An LS9 chevy has forged pistons, while the n/a LS7, with a 600 rpm higher rev limit, has cast pistons in it instead. Cylinder pressures are highest at lower engine speeds, and this problem is exacerbated by adding a supercharger. Dizduster brings up a good point regarding timing but that is only one piece of the puzzle.