Perf. Piston Ring Set V8 4.065 Bore 1.2x1.5x3.0

The Perf. Piston Ring Set V8 4.065 Bore 1.2x1.5x3.0 is a precision-engineered ring pack designed for high-performance V8 engine builds and rebuilds. This NPR piston ring set addresses the critical function of sealing combustion pressure, controlling oil consumption, and managing heat transfer between the piston and cylinder wall. Whether you're restoring a classic big-block, building a street performance engine, or preparing for competition, quality piston rings are non-negotiable for longevity and reliability.

This set features a 1.2mm top ring, 1.5mm second ring, and 3.0mm oil control ring configuration—a proven three-piece design that balances seal integrity with low friction and efficient oil return. The 4.065-inch bore specification ensures precise fitment in bores expanded to that dimension through honing or sleeving. NPR's performance-grade rings are manufactured to tight tolerances and often employ advanced materials and coatings that reduce blowby, improve ring-to-groove conformity, and extend service life under sustained high-RPM operation compared to economy-grade alternatives.

This ring set is ideal for engine builders and experienced mechanics tackling custom V8 projects where bore size has been increased to 4.065 inches—common in stroker builds, overbore restorations, or modified performance applications. Proper installation requires careful piston-to-bore clearance verification, ring end-gap filing to specification, and meticulous cleanliness during assembly. Always verify your block's actual bore size and confirm this set matches your piston specifications before ordering, as proper fitment is critical to engine performance and reliability.