Perf. Piston Ring Set V8 4.070 Bore 1.5x1.5x3.0

The Performance Piston Ring Set V8 4.070 Bore 1.5x1.5x3.0 from NPR Piston Rings is engineered for serious engine builders and enthusiasts seeking reliable compression sealing in big-block and stroker V8 applications. Whether you're rebuilding a classic muscle engine, restoring a high-displacement platform, or completing a custom build, this precision ring set delivers the sealing geometry needed to maintain combustion pressure and prevent blow-by across the full RPM range. NPR's reputation for manufacturing quality ensures consistent bore fitment and ring tension that resists premature wear.

This ring set features a 1.5mm top ring, 1.5mm second ring, and 3.0mm oil ring stack—a proven compression and oil control geometry that balances ring flutter resistance with effective scraping of cylinder wall oil film. The 4.070-inch bore size accommodates large-displacement V8 engines commonly found in performance and racing platforms. NPR's manufacturing tolerances ensure each ring seats properly against the piston groove without binding, critical for preventing micro-welding during high-load operation. The three-piece oil ring design separates the scraper and expander functions, allowing precise oil film management while the compression rings maintain peak pressure sealing throughout the combustion cycle.

This piston ring set is ideal for engine rebuilds, performance upgrades, and custom V8 applications requiring robust sealing in the 4.070-inch bore window. Proper installation requires careful ring-gap filing to match your specific cylinder bore and piston configuration—critical for eliminating compression leakage and oil burning. Compatibility is limited to pistons with 4.070-inch bore diameter and standard three-ring groove spacing; verify your piston and cylinder dimensions before purchase. This ring set suits naturally aspirated and forced-induction builds where reliable sealing directly impacts power delivery, efficiency, and engine longevity.