ARP Billet Bore Tapered 87.5mm Piston Ring Compressor 901-8750

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 Ring Compressors are CNC-machined from 6061-T6 billet tube material with a true radius for every bore diameter. The true radius design is far superior to conventional "tapered" devices and widely used by professional engine builders. Compressors are relieved on the bottom for wire O-rings and Type 3 anodized for long life.