Quote Originally Posted by TRYMY4.0
my suggestion is, if you are going to do the crank pulley, make sure you do it on a motor build. DOnt just slap it on your factory motor. If you get ur motor rebuilt the crank, pistons, everything will be balanced. Your old motor will prob wear out even faster or do some mighty damage
this is only true with engines that use harmonic balancers on the crank pullies... most modern import engines are balanced internally from the factory and decreasing the rotational mass using a lightweight flywheel and/or crankpulley will not throw the engine out of balance, meaning it will not hurt the main bearings or the oil pump rotors...