Clevite MS-1948A-20 Engine Crankshaft Main Bearing Set

The Clevite MS-1948A-20 is a precision-engineered main bearing set designed to provide reliable crankshaft support and optimal oil delivery in performance and racing applications. This bearing set features proven tri-metal construction with careful attention to bearing geometry, crush specifications, and oil film management for demanding engine builds.

Key Features:

• Tri-metal bearing construction for strength and durability
• Optimized bearing geometry for proper oil film development
• High crush design for maximum bearing retention
• Reduced overlay thickness to prevent overlay fatigue
• Engineered grooving to balance main bearing performance with rod bearing oil supply
• Non-flash plated for improved seating characteristics

Understanding Main Bearing Design:

Main bearing performance depends on maintaining a pressurized oil film between the bearing surface and crankshaft. The upper main shells typically feature 180-degree grooving to deliver oil to connecting rod bearings, while lower shells remain ungrooved to maximize oil film thickness under load. This asymmetric design provides the best balance between adequate rod oiling and optimal main bearing life.

Clevite Performance Bearing Series Overview:

Clevite offers several bearing series for different performance applications. P-Series bearings feature maximum eccentricity for high-RPM applications where severe rod bore distortion occurs, with full-groove mains to maximize oil flow. H-Series bearings provide medium eccentricity with enlarged chamfers for oversize crankshaft fillets, ideal for medium to high-RPM engines. K-Series bearings add proprietary moly/graphite TriArmor surface treatment for enhanced protection during start-up and high-load conditions. V-Series bearings use lead-indium overlay for superior conformability. M-Series bearings feature thick babbitt lining for maximum conformability in engines with severe crankshaft deflection.

Proper bearing selection depends on your specific application requirements, including RPM range, crankshaft specifications, and bearing contact pattern analysis. This Clevite main bearing set delivers the precision and durability needed for serious performance engine builds.