Piston Ring Set 4.185 Moly 1/16 1/16 3/16

The Piston Ring Set 4.185 Moly 1/16 1/16 3/16 is a premium race-series piston ring kit engineered for high-performance engine applications requiring precision bore fitment and sustained thermal stability. This eight-cylinder ring set combines plasma moly coating with ductile iron construction to deliver superior ring life and consistent blowby control in demanding racing environments where conventional rings fall short.

The 4.185-inch bore diameter is matched with a file-fit design, requiring hand-finishing to achieve the exact clearances your specific engine demands. The ring thickness specification—1/16 inch top compression ring, 1/16 inch second compression ring, and 3/16 inch oil control ring—follows proven race engine geometry. Plasma moly coating on the compression rings provides a low-friction sealing surface that resists scuffing during high-RPM operation while maintaining proper contact pressure against cylinder walls. Standard tension characteristics ensure balanced ring dynamics without excessive drag or blowby leakage across the full operating range.

This piston ring set is designed for engine builders and racing enthusiasts who require tight manufacturing tolerances and material science proven in competitive motorsports. File-fit rings demand careful fitment procedure—proper ring gap spacing and bore preparation are critical to achieving optimal sealing and longevity. Whether preparing a naturally aspirated or forced-induction race engine, this kit provides the friction reduction and thermal management necessary for sustained performance at extended RPM.

SKU JEPJ100F8-4185-5 ships as a complete eight-cylinder set. Verify your engine's exact bore diameter and ring groove dimensions before final installation, as file-fit rings require precise finishing to specification.