Clevite MS-1687P-20 P-Series Main Bearing Set

The Clevite MS-1687P-20 is a high-performance P-Series main bearing set engineered for demanding racing and performance engine applications. This bearing set features a 180-degree groove in the upper shell design that optimizes oil film development while maximizing oil delivery to connecting rod bearings.

Key Features:

• P-Series design with high eccentricity for extreme RPM applications
• Full groove configuration maximizes oil flow to rod bearings
• High crush design ensures maximum bearing retention
• Reduced overlay thickness prevents overlay fatigue and hen tracking
• Hardened steel back construction for added strength and fretting resistance
• Enlarged chamfers provide superior crankshaft fillet clearance
• No flash plating for improved bearing seating
• TriMetal bearing construction for legendary durability

Applications:

P-Series main bearings are ideal for high-RPM racing engines experiencing severe rod bore close-in conditions. These bearings provide increased oiling capacity to prevent rod bearing oil starvation, which typically manifests as surface polishing, smearing, and discoloration concentrated at the bearing's axial center. The higher eccentricity design narrows bearing contact patterns while ensuring adequate lubrication reaches connecting rod bearings under extreme operating conditions.

Performance Benefits:

The 180-degree upper shell groove represents the optimal balance between oil delivery and oil film strength. This design maintains peak bearing performance by developing a thick hydrodynamic oil film in the loaded lower bearing zone while providing sufficient oil supply through the upper shell groove. The result is improved bearing life, reduced peak oil film pressure, and minimized horsepower loss compared to extended groove designs.

Clevite engine bearings are manufactured to exacting tolerances and represent over a century of bearing engineering expertise, making them the preferred choice for professional engine builders and racing teams worldwide.