NPR SWG10031-1 GM 6.0L LS Engine Nitride Piston Ring Set 1.20/1.50/2.50mm Standard Bore

The NPR SWG10031-1 is a standard bore nitride piston ring set designed for GM 6.0L LS-series gasoline engines. Manufactured by Nippon Piston Ring Co., Ltd. (NPR) — Japan's original and most trusted piston ring manufacturer since 1931 — this ring set delivers OEM-quality sealing performance for engine rebuilds and overhauls.

This set features ring widths of 1.20mm (top compression), 1.50mm (second compression), and 2.50mm (oil control), with a nitride surface treatment on the compression rings for superior wear resistance and extended service life. Nitrided rings harden the contact surface to reduce friction and resist scuffing under the high heat and pressure conditions found in modern high-output engines.

Key Features:

• Designed for GM 6.0L LS-series gasoline engines — standard bore
• Ring dimensions: 1.20mm top / 1.50mm second / 2.50mm oil control
• Nitride surface treatment for enhanced wear resistance and durability
• Seals combustion gas, controls lubricating oil, and dissipates heat
• Manufactured to strict JIS (Japan Industrial Standard) B8032 specifications
• Steel ring construction provides higher tensile strength and reduced ring mass versus cast iron
• Engineered and tested in cooperation with engine manufacturers to ensure proper fit and function
• Reduces oil consumption and blow-by for cleaner, more efficient engine operation

NPR piston rings undergo rigorous bench and engine testing to validate material composition and surface treatment prior to release. The SWG10031-1 is the standard (STD) size variant of the SWG10031 ring set family, making it the correct choice when cylinder bores are within factory specification or have been honed to standard dimensions.