The valves suck, the manifolds are tiny, the rods are light and weak, the pistons are crap, the fasteners are junk, the crank has thin rod journals, and the wrist pins are dinky. -jafro

....what could i do about the valves as well? is there an aftermarket performance valve kit? aftermarket rods will fix the rod problem, and im hoping the "crap" pstons will be enough for my n/a application...but what about the fastners? and the wrist pins? would that be too much trouble to fix? or would it even matter below the 150 hp range?