Clevite MS-2248P-.25MM Main Bearing Set Undersized Performance

The Clevite MS-2248P-.25MM is a high-performance main bearing set designed for demanding engine applications. This P-Series bearing features 0.25mm undersize dimensions to accommodate machined crankshafts while maintaining proper oil clearances.

P-Series Performance Features:

• High eccentricity design maximizes oil film thickness and bearing contact optimization
• Full groove upper shells provide maximum oil flow to connecting rod bearings
• High crush design ensures superior retention in the engine block
• Reduced overlay thickness prevents overlay fatigue and "hen tracking" under high loads
• Hardened steel backing provides exceptional strength and fretting resistance
• TriMetal construction combines durability with performance

Optimal Applications:

P-Series main bearings excel in high-RPM performance engines where maximum oil delivery to rod bearings is critical. The higher eccentricity design narrows bearing contact patterns to ideal 2/3 to 3/4 coverage, preventing excessive bearing contact while ensuring adequate load support. This series is particularly effective in combating rod bearing oil starvation, which typically manifests as surface polishing, smearing, or discoloration concentrated at the bearing's axial center.

Design Philosophy:

Clevite's bearing grooving research demonstrates that the optimized 180-degree groove in the upper shell provides the best balance of oil delivery and film strength. The ungrooved lower shell maintains maximum oil film thickness in the heavily loaded zone, improving safety margins and bearing longevity. This configuration delivers superior performance compared to full-grooved or extended-groove designs, which compromise oil film development and increase both horsepower loss and peak oil film pressure.

The undersize 0.25mm dimension accommodates crankshafts that have been ground to restore proper geometry or remove surface damage, making this bearing set ideal for engine rebuilds and performance applications requiring precision clearances.