MAHLE 42081CP.030 Premium Plasma-Moly Engine Piston Ring Set Oversize - 0.030

The MAHLE 42081CP.030 is a premium OE-replacement piston ring set engineered for engines bored +0.030" oversize. Built to the same exacting standards as original equipment, this set delivers superior sealing performance, reduced oil consumption, and extended engine life. MAHLE is one of the largest OE piston ring manufacturers in the world, and this set reflects their industry-leading engineering and materials technology.

Key Features:

• SAE 9254 High-Alloy Steel Base Material — delivers higher tensile and yield strength, extended fatigue resistance, and increased material hardness compared to standard steel
• Plasma-Moly Top Ring Facing — provides excellent break-in characteristics and long-term wear resistance for the upper compression ring
• Barrel-Faced Compression Ring Profile — promotes more efficient compression and reduces blow-by for optimal power retention
• CNC-Controlled Gap Chamfer — precision-machined gap geometry optimizes compression sealing and minimizes combustion gas leakage
• Napier-Style Second Ring — reverse-twist design with taper-race machining provides superior oil control, improved combustion gas management, and enhanced top ring stability
• CP-20 Three-Piece Oil Ring Assembly — exclusive 20° ear angle delivers the best possible side seal against the cylinder wall; chemically polished expander promotes enhanced oil drain-back
• Pre-Lapped Design — rings are installer-friendly and seat immediately, virtually eliminating traditional break-in time
• +0.030" Oversize — designed for engine blocks that have been bored and honed 0.030" over standard bore diameter

Ring materials, coatings, and tension values are all application-optimized to reduce friction and deliver the longest possible service life. The MAHLE 42081CP.030 piston ring set is the trusted choice of professional engine builders seeking OE form, fit, and function in a rebuilt engine.