Mahle MS 4.145in +.005in 1.0mm 1.0mm 2.0mm File Fit Rings

Mahle is a well-known name in engine components, often supplying parts for original equipment manufacturers. This file fit piston ring set, part number 4150MS-112, is designed for engine rebuilds where you need to precisely set the piston ring gap to match your specific cylinder bore and application.

This set features rings with a 1.0mm top ring, a 1.0mm second ring, and a 2.0mm oil ring. The key feature here is that they are 'file fit,' meaning the ends of the rings are not pre-gapped. This allows you to carefully file them down to achieve the exact clearance needed for your engine build, which is crucial for proper sealing and performance, especially in modified or performance applications. The rings are also specified as +.005in, indicating they are intended for a bore that is five-thousandths of an inch larger than standard.

Because these are file fit rings, they require careful measurement and adjustment during installation. It's important to have the correct tools and knowledge to ensure the ring gap is set accurately. Please note that this set is not CARB approved and cannot be shipped to California.