AP Steel Piston Ring Set 4.125 Bore

The TOTAL SEAL AP Steel Piston Ring Set 4.125 Bore (TS9010 5) is a precision-engineered ring kit designed for 4.125-inch bore engines requiring file-fit installation and advanced sealing performance. This complete 8-cylinder piston ring set combines Total Seal's proprietary advanced profiling technology with a gapless second ring design, delivering superior compression sealing and reduced blowby across the full operating range.

The ring set features 0.043-inch top and second ring thicknesses with a 3.0mm radial thickness, manufactured from steel in natural finish. Standard tension design provides reliable performance without excessive friction or wear. The gapless second ring eliminates the gap between the top and second rings, reducing high-pressure gas escape and improving ring-to-bore sealing efficiency—a critical advantage in high-compression and boost applications. File-fit installation ensures precise bore-to-ring clearance for optimal performance in custom or competition builds where factory tolerances may not apply.

This piston ring kit serves engine builders and serious engine rebuilders who demand measurable improvements in compression retention and combustion efficiency. Total Seal rings are commonly specified in performance rebuilds, race engine applications, and high-boost forced-induction builds where factory ring designs reach their limits. The 4.125-inch bore size targets a specific segment of small-block and mid-displacement engine platforms, making this kit essential for builders working with these specifications.

Total Seal piston rings have established a reputation in the performance engine market for consistent quality and measurable sealing benefits. File-fit rings demand precise installation technique and bore preparation, so proper honing and ring gapping procedures are essential before installation. This ring set is sold as a complete kit with all rings necessary for one 8-cylinder engine.