Clevite MS-909A-30 Engine Crankshaft Main Bearing Set

The Clevite MS-909A-30 is a high-performance engine crankshaft main bearing set designed for demanding automotive applications. This precision-engineered bearing set provides superior lubrication and durability for performance and racing engines.

Key Features:

• Tri-metal construction with hardened steel backing for maximum strength
• Optimized bearing grooving design for improved oil film development
• High crush design ensures maximum bearing retention
• Reduced overlay thickness prevents overlay fatigue
• Enlarged chamfers provide increased crankshaft fillet clearance
• No flash plating for superior bearing seating

Performance Engineering:

Clevite main bearings utilize advanced bearing grooving technology to optimize oil film development. The upper main shells feature a 180-degree groove to supply connecting rods with oil, while the lower shells remain ungrooved to maintain the thickest possible oil film for maximum load capacity. This design provides superior shaft separation and extended bearing life under high-performance conditions.

Series-Specific Design:

Clevite offers multiple bearing series to match specific engine requirements. P-Series bearings feature high eccentricity with full grooving for maximum oil flow to rod bearings, ideal for extreme RPM applications. H-Series bearings provide medium eccentricity with 180-degree upper grooving, suitable for NASCAR and competition engines running medium to high RPM ranges. K-Series bearings add proprietary moly/graphite TriArmor coating for enhanced protection during start-up and high-load conditions. V-Series bearings utilize lead-indium overlay for superior conformability, while M-Series Micro bearings feature .006-inch thick babbitt lining for maximum conformability in engines experiencing severe crankshaft deflection.

Application Notes:

Select bearing series based on your specific engine requirements. Use P-Series for extremely high RPM applications with severe rod bore close-in. Choose H-Series for crankshafts with oversize fillets and medium to high RPM operation. K-Series bearings are recommended when additional dry-film protection is desired. V-Series suits applications requiring lead-indium overlay conformability, and M-Series is designed for engines with severe crankshaft deflection causing edge loading.

This main bearing set is precision-manufactured to OEM specifications and is suitable for street performance, racing, and competition applications requiring superior bearing technology.