MAHLE 40134CP-030 Precision-Ground Performance Piston Ring Set 4.080 in. Bore Moly 8-Cylinder

The MAHLE 40134CP-030 is a precision-ground performance piston ring set engineered for 8-cylinder engines with a 4.080-inch bore at a +0.030-inch oversize. Manufactured to OE-equivalent standards, this moly ring set delivers reliable compression sealing, superior oil control, and long service life — making it an ideal choice for engine rebuilds and re-ring jobs.

Key Specifications:

• Bore Diameter: 4.080 in. (+0.030 in. oversize)
• Top Ring Thickness: 5/64 in. — moly-faced for durability under severe operating conditions
• Second Ring Thickness: 3/32 in.
• Oil Ring Thickness: 3/16 in. — 3-piece assembly with stainless steel expander
• Cylinder Count: 8-cylinder set
• Material Grade: Premium

Key Features:

• Moly-faced top compression ring provides long life under high heat and pressure
• 3-piece oil ring assembly uses a stainless steel expander between two chrome-faced steel rails for maximum cylinder wall conformability
• High-strength materials with special ring face contours and torsional designs ensure optimum compression sealing and oil control
• Foolproof installation design prevents incorrect ring fitment, saving time during assembly
• Manufactured under strict quality controls to OE-grade tolerances
• Sold as a complete set

MAHLE is the world's largest piston ring manufacturer, with over 60% of production engines built in North America using MAHLE pistons or rings. The 40134CP-030 brings that same OE engineering expertise to the aftermarket, giving engine builders a proven, high-quality solution for performance rebuilds.