Perf. Piston Ring Set V8 4.055 Bore 1.2x1.2x3.0

The NPR Performance Piston Ring Set V8 4.055 Bore 1.2x1.2x3.0 is purpose-built for V8 engine builders and experienced mechanics undertaking a full rebuild or top-end refresh on American high-performance applications. This eight-cylinder ring kit addresses one of the most critical components in any engine's internal architecture—the rings that seal combustion pressure, control oil consumption, and directly impact power delivery and durability. Whether you're restoring a classic muscle car, upgrading a street performance engine, or preparing a competition build, these rings deliver the precision fit and material quality that serious enthusiasts demand when every detail counts.

Engineered from hardened steel with a nitride surface treatment, the Perf. Piston Ring Set V8 4.055 Bore features a 1.2x1.2x3.0 mm profile in standard tension—a configuration optimized for reliable sealing across a wide RPM range while maintaining reasonable blowby control. The nitride coating dramatically increases wear resistance and reduces friction at the ring-to-cylinder wall interface, a critical factor in minimizing parasitic losses and extending ring life under sustained boost or high-RPM operation. The 4.055-inch bore specification matches common V8 overbore dimensions, making this kit compatible with long-block assemblies that have been sized to this precise tolerance. Standard tension characteristics ensure proper fit without excessive groove pressure that could damage piston lands, while still maintaining the sealing integrity required for modern fuel injection and emissions compliance on street-driven builds.

This ring set is ideal for engine builders machining to 4.055-inch bore specifications, whether for stock displacement builds, 0.030-over overbores, or custom stroker combinations requiring precision top-end sealing. Installation requires proper honing to the correct surface finish and ring gap set-to-spec before final assembly—critical steps that separate professional rebuilds from rushed jobs. Verify your piston's ring groove dimensions and your engine block's final bore size before ordering to ensure perfect fitment. When paired with quality pistons, gaskets, and proper assembly technique, the NPR Performance Piston Ring Set V8 4.055 Bore delivers the combustion sealing and oil control necessary for reliable, long-term performance on both street and strip applications.