Clevite MS-909P-30 P-Series High Performance Main Bearing Set

The Clevite MS-909P-30 is a high-performance main bearing set from the legendary P-Series line, engineered for demanding racing and performance applications. These precision bearings feature advanced TriMetal construction with a hardened steel back, aluminum alloy intermediate layer, and a thin lead-tin-copper overlay optimized to prevent overlay fatigue in high-stress conditions.

P-Series Design Features:

• Full 360-degree grooving in upper shells to maximize oil flow to connecting rod bearings
• High crush design for maximum bearing retention in extreme conditions
• Reduced overlay thickness to eliminate hen tracking and overlay fatigue
• Increased eccentricity to narrow bearing contact patterns and improve oil distribution
• Hardened steel backing for superior strength and resistance to fretting

Ideal Applications:

• Engines operating at extremely high RPM where severe rod bore close-in occurs
• Applications requiring increased oil flow to rod bearings to prevent starvation
• Racing engines where maximum bearing retention is critical
• Builds experiencing rod bearing polishing, smearing, or discoloration at axial center

The P-Series represents Clevite's oldest and most proven high-performance bearing technology, trusted by engine builders for decades. These bearings are designed to handle the extreme loads and temperatures of competition use while providing reliable performance and extended service life. The full-groove design ensures adequate lubrication reaches the rod bearings even under the most demanding conditions.

Note: P-Series bearings have the greatest amount of eccentricity among Clevite performance bearings. If contact patterns are too narrow, consider H-Series bearings with medium eccentricity. Optimal contact patterns should cover 2/3 to 3/4 of the bearing surface.