Billet aluminum ims to crankshaft chain guide/tensioner, replacement for Porsche part no. 996 105 165 55, to help prevent catastrophic engine failures like this. Shown below is a comparison of our billet tensioner paddle compared to the cast factory tensioner. Billet construction provides a significantly stronger and more durable product while utilizing oe Porsche wear pad and pressure pin (both of which are included as shown). Update: we 've found the factory plastic pressure pin to not be strong enough, so we 've made a billet steel pressure pin against which the chain tensioner actuates to tension the crankshaft to ims drive chain. This is a return to a style of pressure pin found in very early examples of the m96 engine.