MAHLE 42266CP.040 Engine Piston Ring Set +0.040" Oversize Premium CP Series

The MAHLE 42266CP.040 is a premium CP-series engine piston ring set ground to a +0.040" oversize bore specification, designed for engine rebuilds requiring cylinder bore restoration beyond standard dimensions. MAHLE Original piston ring sets are engineered to be installer-friendly and come pre-lapped to seat immediately, virtually eliminating break-in time.

Key Features:

• Ring materials, coatings, and ring tension are all optimized for reduced friction and extended service life.
• Compression rings feature a barrel-faced contact area for more efficient compression and CNC-controlled gap chamfer to optimize compression and reduce blow-by.
• Intermediate rings utilize a reverse twist design for better groove side sealing and taper race machining to enhance contact.
• CP-20 oil ring assemblies feature a 20-degree ear angle for the best possible side seal against the cylinder wall, and a special chemical polish on the oil ring expander for enhanced oil drain back.
• Whether repairing a modern computer-controlled engine or rebuilding an older engine, MAHLE Original piston ring sets (formerly Perfect Circle) have been trusted by professional automotive technicians for over 100 years.

MAHLE is the world's leading manufacturer of more than 100,000 OE and aftermarket parts, including pistons and piston rings for a wide range of automotive applications. The 42266CP.040 delivers OE-quality sealing performance for a reliable, long-lasting engine rebuild.