MAHLE 8750MS-12-1 Sport Compact Piston Ring Set 87.50mm Bore Single Cylinder

The MAHLE 8750MS-12-1 is a single-cylinder sport compact piston ring set engineered for 87.50mm bore applications. Designed for performance street and motorsport engines, this drop-in ring set delivers a precise, reliable combustion seal to prevent blow-by gases from entering the crankcase and to keep oil out of the combustion chamber.

This set features a 1.2mm / 1.2mm / 2.8mm ring pack — a thin-ring configuration well suited to high-revving sport compact engines where reduced ring tension translates to lower friction and improved power output. MAHLE engineered these rings using piston ring simulation and computer development tools to minimize friction and maximize ring-to-piston sealing efficiency.

Ring Construction:

• Top Ring (1.2mm): Stainless steel with a gas nitrided face coating for superior wear resistance and scuff protection
• Second Ring (1.2mm): Reverse-twist cast iron for effective oil control and combustion sealing
• Oil Control Ring (2.8mm): 3-piece standard-tension design with chrome-plated stainless steel rails for consistent oil film regulation

Key Features:

• 87.50mm bore diameter — drop-in fit, no file fitting required
• Ring thicknesses: 1.2mm top / 1.2mm second / 2.8mm oil control
• Steel nitrided top ring for enhanced durability and scuff resistance
• Standard tension oil control ring for reliable oil regulation
• Part of MAHLE's sport compact ring series covering 81–100mm bore sizes
• Sold as a single-cylinder set (4 rings total)

MAHLE Motorsport is a globally recognized leader in performance piston and ring technology, trusted by race engineers worldwide for reliability and precision. The 8750MS-12-1 single-cylinder set is ideal for builders sourcing rings by the cylinder rather than purchasing a full multi-cylinder set.