ARP Billet 83.5mm Bore Tapered Piston Ring Compressor

This ring compressor has a tapered inner surface that helps you slide the piston into the block with the rings installed. As the piston slides down the cylinder, the rings push into the ring-lands allowing the piston to slide into the bore. Its a must-have for assembling your engine.
ARP’s new ring compressors are CNC machined from 6061- T6 billet tube material and feature a true radius for each different bore diameter. What’s more, they are relieved for wire O-rings on bottom. Type 3 anodizing is used for long life, and the bore size is prominently engraved in 3/4 high numbers for easy identification. Standard stocking sizes from 3.552 to 4.750 (SAE) and 75mm to 100mm (metric). The true radius design is far superior to conventional “tapered” devices, and widely acclaimed by professional engine builders! This is truly the very best piston ring compressor on the market today.