What happens when you put a flywheel for a stock 429 on a stroked 557 cube engine? So glad you asked! It makes 6 successful dyno pulls and then after some tweaks and hitting the 850hp number the flywheel lets go, ruining the engine and jettisoning itself through a wall and into another room. Thankfully no one was injured by this act of carelessness. Just more reason to use the right parts instead of settling for ones that will do in a pinch!