MAHLE 42081CP.020 Original Engine Piston Ring Set - .020 Over Plasma-Moly

The MAHLE Original 42081CP.020 is a premium .020-inch oversized engine piston ring set engineered to OE form, fit, and function specifications. Designed for engine rebuilds requiring a .020-inch overbore, this set delivers the same quality and precision found in original equipment applications, restoring proper compression, minimizing blow-by, and controlling oil consumption.

MAHLE piston rings are manufactured from SAE 9254 high-alloy steel, providing superior tensile and yield strength, extended fatigue resistance, and increased material hardness compared to standard ring materials. The compression rings feature a barrel-faced contact area for more efficient sealing and a CNC-controlled gap chamfer to optimize combustion chamber sealing and reduce blow-by.

Key Features:

• SAE 9254 high-alloy steel construction for enhanced strength, hardness, and fatigue resistance
• Plasma-moly top ring coating for excellent wear resistance and fast break-in
• Napier-style second ring for superior oil control, improved combustion gas management, and top ring stability
• Exclusive CP-20 oil ring assembly with a 20-degree ear angle for optimal side sealing in the piston oil ring groove
• Special chemical polish on the oil ring expander for enhanced oil drain-back
• Pre-lapped rings seat immediately, virtually eliminating traditional break-in time
• Ring materials, coatings, and tension optimized for reduced friction and extended service life
• .020-inch oversized for engines that have been bored or honed oversize during rebuild

MAHLE is one of the world's largest OE piston ring manufacturers, supplying rings to the majority of North American engine production. The 42081CP.020 piston ring set reflects that same OE-level engineering and quality control, making it the trusted choice for professional engine builders and rebuilders.