4.170 Tapered Ring Compressor

The ARP 4.170 Tapered Ring Compressor is an essential tool for any serious engine builder, machine shop, or performance mechanic working with large-displacement or high-performance piston assemblies. This piston ring compressor is specifically engineered for bores measuring 4.170 inches—a common displacement across big-block V8s, stroker motors, and custom engine builds. Whether you're assembling a fresh long-block, performing a complete rebuild, or installing performance pistons, this compressor ensures rings seat cleanly into the cylinder without binding, cracking, or scoring the bore walls.

Constructed from black anodized aluminum, the ARP 4.170 features a precision-tapered design that compresses piston rings concentrically while guiding the piston smoothly into the bore. The tapered profile reduces friction and prevents ring hang-up—a critical failure point that can lead to bent or broken rings before the piston is fully seated. Aluminum construction keeps weight minimal during installation while maintaining rigidity, and the anodized finish resists corrosion even in humid shop environments. The 5.75-inch length and 2.25-inch width provide a comfortable working envelope, and at 0.68 pounds, it's light enough for extended hand use without fatigue.

This compressor is ideal for restoration shops, race teams, and hardcore enthusiasts rebuilding big-block Chevys, Fords, Mopars, and other muscle-car platforms with 4.170-inch bore spacing. It's equally valuable in performance shops installing forged piston kits or oversized pistons in stroker applications. Buy this piston ring compressor for review-quality assembly results and long-term reliability; ARP's precision engineering ensures it will remain a staple in your tool collection for decades of builds. Compatible with any piston design that fits a 4.170-inch bore, it's a one-time investment that pays dividends across dozens of projects.