GTM Performance Engineering: VQ37VHR Engine Build 700HP Power Package

Originally Posted by phelan

Angry much, Mike? lol

Well...probably as good an excuse as any to build something nice. It's a wreck going into GTM, let's see how it comes out.

Originally Posted by Xracer

Wow that is some serious damage, the flywheel bolts completely sheared off? That is some serious force. Its hard to tell from the pictures, but at a glance it actually doesnt look like pre-ignition is the cause for this. Generally with engines that fail from pre-ignition, they show evidence of the phenomenon prior to the actual failure. At the same time the cylinder pressures sky rocket, the temperatures do so as well. The shock and heat literally degrade and melt corners or sharper edges of the aluminium pistons and head. One thing to consider is the torsional vibration or resonance characteristics resulting from the Stillen pulley.

Although a billet pulley is good for reducing rotating inertia, I am a strong believer that they only belong on accessories ( AC, PS etc..) This can get pretty involved physics, wise but in a nut shell, your engine's rotating assembly behaves much in the way that your suspension does. Your car's suspension takes a step input (a bump in the road), the spring stores some of the energy, and the damper dissipates it. This spring-mass-damper system is just like an engine's combustion (the bump in the road), pistons-rods-crank (spring and mass)...but where is the damper?! Most OEM Crank pulleys are not solid metal through and through actually. Most have rubber embedded in them or a viscous fluid. The rubber or fluid is the damper.

This may sound far fetched but you'd be surprised what can happen when the rotating assembly in an engine experiences resonance. It could very well end up looking like that poor engine. In any spring-mass-damper system, if you chance one of the components, you change the response of the system to any input. And hey, these engines operate over a frequency range from 0 to 7500rpm... plenty of room for strange things to happen.

Anyways, absolutely nothing against stillen or anything. Just thought i'd bring awareness to the subject. Lack of tuning/knock is the most common reason for engine failure like that.