Piston Ring Set 4.150 1.5 1.5 3.0mm

The MAHLE PISTONS Piston Ring Set 4.150 1.5 1.5 3.0mm (part number 4150MS-15) is a performance-grade piston ring kit engineered for high-output 8-cylinder engines requiring precise bore fitment. Designed for 4.150-inch bore applications, this file-fit ring set delivers the compression seal and blow-by control critical to sustained power output and engine durability in both naturally aspirated and forced-induction builds.

Each ring in this set measures 1.5 × 1.5 × 3.0mm thick and features plasma moly surface treatment, a hard-facing process that reduces friction and extends ring and bore life under sustained load. The compression ring and oil control ring geometry is optimized for standard tension applications, meaning it balances sealing effectiveness against cylinder wall wear. Ductile iron construction provides the fatigue resistance necessary for extended operation at elevated RPM, while the file-fit design allows builders to customize ring end-gaps during assembly to match their specific displacement, boost level, and fuel type.

This ring kit is intended for engine builders and machine shops assembling big-displacement or boosted 8-cylinder engines where OEM replacements are insufficient. Typical applications include street performance builds, race engine assembly, and engine rebuilds where elevated cylinder pressures demand superior sealing and thermal management. The 4.150-inch bore specification aligns with common stroker and bored-over V8 platforms.

MAHLE Pistons is recognized as a tier-one OEM supplier, and its performance piston ring line reflects the same precision manufacturing and material science applied to factory engine programs. File-fit rings require proper gap setting and installation technique—this is a builder-grade component, not a bolt-in replacement.