Piston Ring Set 4.085 1.5 1.5 3.0mm

The Piston Ring Set 4.085 1.5 1.5 3.0mm from MAHLE PISTONS is engineered for serious engine builders and enthusiasts seeking reliable, high-performance internal engine components. This file-fit piston ring set is designed for 8-cylinder engines with a 4.085-inch bore diameter and serves as a critical upgrade path for those rebuilding or performance-tuning their powerplants. Whether you're assembling a competition engine, restoring a classic, or optimizing daily-driver performance, this ring set delivers the precision and durability that professional machinists and engine shops demand.

Manufactured from ductile iron with a plasma moly coating, the Piston Ring Set 4.085 1.5 1.5 3.0mm combines material science with proven ring design to maximize ring-wall contact and seal integrity. The ring dimensions—1.5mm top ring, 1.5mm second ring, and 3.0mm oil ring—are optimized for compression retention and blow-by control, while standard tension characteristics ensure proper seating and long service life across varying load conditions. The plasma moly surface treatment reduces friction, extends ring and cylinder wall life, and improves cold-start performance by lowering initial wear rates during critical break-in periods.

This file-fit ring set is ideal for builders who machine their own pistons or work with custom-spec forged pistons requiring precision gap closure. Installation demands proper ring end-gap measurement and honing of the cylinder bore to OEM or specification tolerances—tasks best handled by experienced engine builders or professional machine shops. The kit is compatible with any 8-cylinder engine featuring a 4.085-inch bore and is particularly valued in LS-series, small-block Chevy, and Ford modular engine platforms where precision internal components yield measurable gains in compression ratio, power output, and durability.