Adjustable Tapered Piston Ring Compressor - Checkered Flag Performance, 3.940" to 4.060" Review

Works well but takes a while to break rhythm. Be patient, it's frustrating at first. Look for instructions on Youtube as there aren't any.

Sorry it took me so long to buy one! It worked wonderfully. It took about 30 seconds to adjust it to the hole size and after that it worked great. Used on 4.00 hp pistons.

Minimum size was 3.953 not 3.900 as described - had to remove 1mm from one edge to reduce diameter to fit 100mm Porsche 944 pistons. Worked very well once the modification was complete, so the tool really matched the description.

I tried this on a 3.928" piston kit. I knew it would be at the limit of the declared tolerance, but the spec is the spec. Unfortunately, it wasn't even close. I set the minimum compressor bore diameter to 3.980 inches.

Scrap - do not buy. Error shrinking to specified size. I had to crop. The anodized finish flaked off during use, so only two pistons could be mounted. After detaching the coating, the rings dig into the case. Purchased the model from Summit Racing and installation was a breeze.

Key too small won't grip 1st or 2nd compression ring. Second try: I opened it up, put it on all the rings and then tightened it again. As the piston entered the bore, the tool began to cock, causing the bottom to be too wide and the top too small. Two tries were enough, it comes back and I used my old one!

It seems to be a great tool but the description is wrong in some places. Declared in places as 3.09"-4.05" and 3.9"-4.05". I don't have piston jugs so this doesn't work for my application. In hindsight the correct male height of 3.9-4.05 inches is much more reasonable, it can't go down to 3.09 inches as that would only compress the ovals and that's a terrible idea. Please correct your descriptions to match the correct title size!