Clevite MS-109P-10 Performance Main Bearing Set

The Clevite MS-109P-10 is a high-performance main bearing set designed for demanding racing and performance engine applications. This P-Series bearing set features specialized engineering to maximize engine protection and oiling efficiency under extreme conditions.

P-Series Performance Features:

• Full groove design maximizes oil flow to connecting rod bearings
• High crush specification ensures maximum bearing retention
• Reduced overlay thickness prevents overlay fatigue and hen tracking
• Hardened steel back construction provides added strength and fretting resistance
• Greater eccentricity narrows bearing contact patterns for optimal performance
• Proven tri-metal bearing construction for durability

Optimized Bearing Groove Design:

Clevite engineers have extensively tested main bearing groove configurations to develop the optimal design. The 180-degree groove in the upper main shell provides the best overall performance by maintaining a thick oil film while still supplying adequate oil to the connecting rods. This design delivers superior bearing life compared to extended groove patterns that can break up the critical oil film and increase peak oil film pressure.

When to Use P-Series Bearings:

P-Series main bearings are ideal for applications requiring increased oil delivery to rod bearings, particularly in high-RPM engines where rod bearing oil starvation may occur. Use P-Series bearings when you need higher eccentricity to narrow bearing contact patterns or when rod bearings show signs of polishing, smearing, or discoloration concentrated at the axial center—all indicators of inadequate oiling.

P-Series bearings represent Clevite's original high-performance bearing line, combining maximum crush for superior retention with specialized features that address the unique demands of racing and performance engines. These bearings use unique core part numbers distinct from standard passenger car applications.