Clevite MS-1039P-30 Engine Crankshaft Main Bearing Set

The Clevite MS-1039P-30 is a high-performance engine crankshaft main bearing set designed for demanding racing and competition applications. This P-Series bearing set features full grooving to maximize oil flow to connecting rod bearings, ensuring optimal lubrication under extreme operating conditions.

P-Series Performance Features:

• Full grooved design maximizes oil delivery to rod bearings
• High eccentricity for narrowed bearing contact patterns
• High crush for maximum bearing retention
• Reduced overlay thickness prevents overlay fatigue and hen tracking
• Hardened steel back construction for added strength and fretting resistance
• TriMetal bearing construction for legendary durability

When to Use P-Series Bearings:

P-Series main bearing sets are ideal for extreme high-RPM applications where rod bore close-in becomes an issue, typically indicated by nearly full parting line contact with standard bearings. The higher eccentricity design narrows bearing contact patterns while providing increased oiling to rod bearings. These bearings are specifically recommended when rod bearing oil starvation is evident, such as polishing, smearing, or discoloration concentrated at the axial center of the bearings.

The full groove configuration in P-Series mains ensures connecting rods receive adequate oil supply even under severe racing conditions. The reduced overlay thickness and high crush design provide maximum retention while preventing the overlay fatigue common in high-performance applications.

Technical Specifications:

• TriMetal bearing construction with reduced overlay
• Full 360-degree grooving for maximum oil flow
• High crush design for superior bearing retention
• Hardened steel back for strength and durability
• .030" undersize for reground crankshafts