Perfect Circle MS2199H1 H-Series Main Bearing Set for GM LS Engines

The Perfect Circle MS2199H1 H-Series Main Bearing Set is designed for Chevrolet LS V8 engines including 4.8L, 5.3L, 5.7L, 6.0L, and 6.2L applications from 1997-2015. This precision bearing set features advanced tri-metal construction with a hardened steel backing, cast copper-lead substrate, and copper-tin-lead overlay for exceptional durability and load capacity in high-performance and competition applications.

Key Features:

• H-Series tri-metal construction designed for NASCAR racing and high-performance applications
• 0.001 inch (0.025mm) undersize for reduced oil clearance on polished crankshafts
• Medium eccentricity and high crush factor for secure installation and optimal bearing retention
• Enlarged chamfers at bearing sides for greater crankshaft fillet clearance
• Steel backing with cast copper-lead alloy center for superior strength and fatigue resistance
• Grooved upper bearings optimize oil flow in high-RPM environments
• No flash plating for improved seating characteristics

Perfect Circle is part of the MAHLE family of brands, which includes Clevite engine bearings. These H-Series bearings are engineered for medium-to-high RPM performance engines and have proven themselves in professional racing applications. The 0.001 inch undersize is ideal for performance builds where the crankshaft has been polished, requiring tighter bearing clearances for optimal oil pressure and engine protection.