Piston Ring Set 4.040 5/64 5/64 3/16

The SEALED POWER Piston Ring Set 4.040 5/64 5/64 3/16 (R934345) is a complete OEM-quality replacement piston ring kit engineered for 8-cylinder engines requiring precise bore and ring specifications. This Speed Pro piston ring set delivers factory performance and longevity across rebuild and restoration applications, combining proven materials with exacting manufacturing tolerances to restore compression and oil control to original specifications.

The 4.040-inch bore dimension accommodates mid-to-large displacement V8 engines across multiple automotive platforms. The ring thickness profile—5/64 inch for the top and second compression rings, 3/16 inch for the oil control ring—matches factory specifications for optimal gas sealing and oil film thickness. The plasma moly coating on compression rings reduces friction and accelerates break-in, while the ductile iron construction ensures durability under high combustion pressures. File fit design allows field-fitting during installation, essential for precision bore matching during engine assembly. Standard tension characteristics provide reliable ring seal without excessive drag on the cylinder wall.

This piston ring kit is specified for complete engine rebuilds, restoration work, and performance machine shops. Engine builders rely on SEALED POWER piston rings for domestic V8 platforms where OEM dimensional accuracy and material quality directly impact long-term reliability. The 8-cylinder configuration and specific bore size make this kit essential for those restoring or rebuilding classic and contemporary American V8 engines.

SEALED POWER maintains a reputation among machine shops and engine builders for consistent manufacturing and ring design that respects original equipment specifications. The Speed Pro line balances affordability with quality, making it a standard choice for professional rebuilds and serious enthusiast engine work.