MAHLE 41787CP.040 Plasma-Moly Piston Ring Set Ford Modular V8 4.6L 5.4L +.040 Oversize

The MAHLE 41787CP.040 is a plasma-moly piston ring set engineered for Ford Modular V8 4.6L and 5.4L engines bored to a +0.040" oversize (3.591" bore). Manufactured to OE form, fit, and function, this ring set delivers the precision and durability demanded by professional engine builders and serious rebuilders alike.

Key Features:

• Plasma-Moly Upper Compression Ring (UCR): RF-13PF plasma-moly faced top ring for superior wear resistance, faster seating, and maximum cylinder sealing
• SAE 9254 High Alloy Steel Base Material: Provides higher tensile and yield strength, extended fatigue resistance, and increased material hardness throughout the ring set
• Napier Second Ring (LCR): RBT-10 reverse-twist design with taper race machining for superior groove side sealing and enhanced oil control — managing up to 80% of oil control function
• CP-20 Oil Control Ring (OCR): Features an exclusive 20-degree ear angle for the best possible side seal in the piston oil ring groove, plus a special chemical polish on the expander for enhanced oil drain-back
• Pre-Lapped for Fast Seating: Rings are pre-lapped at the factory, virtually eliminating break-in time
• CNC-Controlled Gap Chamfer: Optimizes compression and reduces blow-by on compression rings
• Ring Specifications: Upper Compression Ring (UCR): 1.5mm | Lower Compression Ring (LCR): 1.5mm | Oil Control Ring (OCR): 3.0mm
• V8 Complete Set: Sold as a complete set for all 8 cylinders

MAHLE is one of the world's largest OE piston ring manufacturers, supplying rings to major automakers and leading the industry in piston ring technology. The 41787CP.040 ring set is optimized to reduce friction and ring mass while minimizing engine oil consumption and delivering longer service life — making it the ideal choice for Ford Modular engine rebuilds requiring a +0.040" overbore.