MAHLE 42239CP.020 Premium Engine Piston Ring Set Oversize - 0.020

The MAHLE 42239CP.020 is a premium-grade engine piston ring set in a 0.020" (0.50mm) oversize configuration, engineered for engines requiring cylinder bore restoration or light overbore rebuilds. Manufactured by MAHLE — the world's largest piston ring manufacturer — these rings are built to exacting OEM-equivalent specifications for dependable sealing, long service life, and consistent performance.

Ring Construction & Materials:

• Upper Compression Ring (UCR): Carbon steel construction with chrome facing — 1.2mm axial height, RF-13U ring type for excellent sealing and wear resistance under high combustion pressure
• Lower Compression Ring (LCR): Ductile iron construction with chrome facing — 1.2mm axial height, THM-17 taper-faced design for superior oil control and inter-ring pressure management
• Oil Control Ring (OCR): Stainless steel construction with chrome facing — 2.5mm axial height, CP-20 shallow groove design with a 20-degree ear angle for maximum cylinder wall contact and uniform tension

Key Features:

• Premium material grade construction meets or exceeds OEM specifications
• CP-20 oil ring design features a 20-degree ear angle for best-in-class side sealing against the cylinder wall
• Special chemical polish on the oil ring expander promotes enhanced oil drain-back efficiency
• Chrome-faced compression rings provide excellent wear resistance and durability under demanding operating conditions
• Ductile iron second ring seats quickly, controls inter-ring pressure, improves cylinder sealing, and aids effective oil control
• 0.020" oversize sizing accommodates standard engine overbore rebuild tolerances
• Ring groove widths: 1.2mm / 1.2mm / 2.5mm

MAHLE piston rings are the choice of professional engine builders and rebuilders worldwide. With over a century of engineering experience and OEM supply relationships with the majority of the world's engine manufacturers, MAHLE delivers the quality and precision required for a reliable, long-lasting engine rebuild.