Review on 💪 Boost Efficiency with the Proform 66785 Piston Ring Filer Manual by Todd Foster

The manufacturer made a critical design error that was easily corrected at the factory. See photo. When grinding piston rings, ALWAYS grind from the outside in to avoid burring on the cylinder wall side of the rings. Engine Rebuild 101. Demo video showing Proform Piston Ring File Tool 66785. Grinding Tutorial Review YouTube's grinding guides show how to use the product according to its design and HOW NOT to use piston ring files - burrs can cut into cylinder walls. Yes, you can take a file and knock off the burrs, but doing so can reduce compression, and it requires a step that I think can easily be eliminated with a simple design fix. XXXX (apparently there is no other product to name here) 80514 seems to be the best choice. I returned it. To the credit of the seller, the return was hassle free and the money was refunded quickly.