Review on 💪 Boost Efficiency with the Proform 66785 Piston Ring Filer Manual by Mack Douglas

Used to overhaul the LS engine. They did a great job and got the job done, but it took a lot of work and time. You'll get faster with it the more you use it. Make sure you use the anchor points to place it on a solid surface. Makes work a lot easier. Don't be fooled, you need to invest some time and energy to use it, but the product does exactly what it promises for a lot less money than the automatic settings. The pen is a bit awkward to use and can cause hand cramps due to its size, otherwise I would have given it 5 stars. Good product.