Mahle MS 3.947in+.005in 1.0mm 1.0mm 2.0mm File Fit Rings

If you're rebuilding the top end of your engine and need to ensure a proper seal between the piston and cylinder wall, this Mahle file fit ring set is a solid option. These rings are designed to be precisely fitted to your specific bore size, which is crucial for optimal compression and oil control, especially in modified or performance applications where standard rings might not offer the perfect fit.

Mahle is a well-known name in engine components, and this set features a 1.0mm top ring, a 1.0mm second ring, and a 2.0mm oil ring. The 'file fit' designation means you'll need to carefully file the end gap of the top ring to match your cylinder bore precisely. This allows for tighter tolerances and improved performance compared to pre-gapped rings, especially if your cylinder walls aren't perfectly standard or if you're running a custom setup. This attention to detail in fitting helps prevent blow-by and ensures the rings seat correctly for better engine efficiency.

Remember that these rings are not CARB approved and cannot be shipped to California. Always refer to your engine's specific service manual for proper installation procedures and ring gap specifications.