Pulled the heads from my old engine this weekend and found a disturbing sight -



This was a low-miles stock engine when I purchased it. I pulled the heads at that time to inspect the cylinders and all looked good. I reinstalled heads with FelPro gaskets and ARP studs. The only other modification to the engine was a DSG gear drive.

This wasn't the only cylinder. Several others showed imprints of the intake valve in the carbon on top of this piston. This one is the worst though as there is an actual indentation in the top of the piston from the exhaust valve.

I think I found the reason this engine always sounded mechanically noisy.