MAHLE 50664CP.040 Engine Piston Ring Set Standard Replacement 4.040 in. Bore

The MAHLE 50664CP.040 is a standard replacement engine piston ring set engineered to OEM specifications for a precise, reliable fit during engine rebuilds or overhauls. The .040 oversize designation indicates this set is designed for cylinders bored 0.040 inches over standard, making it a direct choice for engines requiring standard oversize ring replacement.

Key Features:

• OEM-grade cast iron construction offering high tensile strength, high yield strength, and excellent hardness with low ring mass
• Pre-lapped rings that seat immediately upon installation, virtually eliminating engine break-in time
• Barrel-faced top compression ring with a CNC-controlled gap chamfer to optimize compression and minimize blow-by
• Reverse-twist intermediate ring with taper race machining for superior groove side sealing and enhanced cylinder wall contact
• CP-20 oil ring assembly featuring a 20-degree ear angle for maximum side sealing against the cylinder wall, plus a chemically polished expander for improved oil drain-back
• Ring tension, materials, and coatings precisely optimized for reduced friction and extended service life
• Ring dimensions: 5/64 in. / 5/64 in. / 3/16 in. (top / intermediate / oil ring thickness)

MAHLE is the world's largest manufacturer of piston rings, with over a century of OE and aftermarket engineering expertise. The 50664CP.040 ring set delivers the stress resistance, minimal groove pound-out, cylinder conformability, and blow-by control demanded by professional engine builders and automotive technicians alike.