MAHLE 3150223 Performance Metric Moly Piston Ring Set HV385 90.0mm 1.0/1.2/2.8mm Standard Tension

The MAHLE 3150223 is a Performance Metric Moly Piston Ring Set designed for 90.0mm bore applications, featuring a 1.0mm / 1.2mm / 2.8mm ring pack configuration with standard tension oil control. This drop-in set is engineered for high-performance and racing applications demanding superior sealing, reduced friction, and long-term durability.

The top compression ring features MAHLE's patented HV385 thermal spray face coating with a micro-polished barrel face. This proprietary coating delivers an exceptionally low coefficient of friction while remaining highly resistant to scuffing against the cylinder wall — a critical advantage under high-load and high-RPM conditions. The base material is SAE 9254 steel for both compression rings, providing unmatched strength and fatigue resistance compared to conventional cast iron alternatives.

The second compression ring utilizes a Napier Taper Hook Groove (THG) design, which scrapes oil from the cylinder wall on each downstroke while also managing combustion gases that bypass the top ring. This dual-function design improves top ring stability, enhances combustion gas management, and minimizes oil consumption. The CP-20 performance oil control ring, named for its 20-degree ear angle, provides the most effective cylinder wall seal available in a 3-piece oil ring assembly.

Key Features:

• Bore Size: 90.0mm
• Ring Pack: 1.0mm top compression / 1.2mm second compression / 2.8mm oil control
• Tension: Standard tension oil control ring
• Top Ring Coating: MAHLE patented HV385 thermal spray with micro-polished barrel face
• Compression Ring Base Material: SAE 9254 high-strength steel
• Second Ring Design: Napier THG (Taper Hook Groove) for superior oil control and gas management
• Oil Ring: CP-20 3-piece assembly with 20-degree ear angle for maximum cylinder wall seal
• Installation: Drop-in fit — designed for bore-specific fitment and proper side seal in the piston ring groove
• Application: Performance metric engines, street/strip, and forced-induction builds

The MAHLE 3150223 ring set is the ideal upgrade for builders working with metric-bore engines who demand race-proven technology with a drop-in installation. MAHLE's bore-specific design philosophy ensures the tightest possible side seal in the ring groove, maximizing compression retention and minimizing blow-by.