The Truth about 318s
O.K,heres the deal with turbo's and why they dont kill an engine.
Boost occurs when the piston is heading down the bore. This is a compressive load which does not create metal fatigue.Max cylinder pressure occurs 20 degrees after tdc in a turbo engine. The turbo only increases peak pressure about 20% but average pressure over the entire stroke is up and so is power.
What kills a motor and metal in general is tensile load or when it is being stretched.So when the piston is at tdc after coming up is when it and the rod are under the most stress. The other big factor here is heat control. Turbo's build heat so you need to control it in order to have a durable engine.
