Clevite MS-1428P-.50MM Main Bearing Set .50mm Undersize

The Clevite MS-1428P-.50MM is a high-performance engine crankshaft main bearing set designed for demanding racing and performance applications. This P-Series bearing set features .50mm undersize dimensions for use with reground crankshafts.

P-Series Performance Features:

• Maximum eccentricity design for extreme high-RPM applications
• Full groove configuration to maximize oil flow to connecting rod bearings
• High crush retention design prevents bearing rotation under severe loads
• Reduced overlay thickness to prevent overlay fatigue and hen tracking
• Hardened steel back construction for superior strength and fretting resistance
• TriMetal bearing construction with lead-tin-copper overlay for excellent wear resistance

When to Use P-Series Bearings:

P-Series main bearing sets are ideal for extremely high-RPM race engines where severe rod bore close-in occurs. These bearings provide higher eccentricity to narrow bearing contact patterns and deliver increased oil supply to rod bearings. They're particularly effective in preventing rod bearing oil starvation, which typically shows as polishing, smearing, and discoloration concentrated at the bearing's axial center.

Engineering and Design:

Clevite's research shows that the optimized 180-degree groove in the upper main shell provides the best overall bearing performance. This design develops a thick oil film while still supplying adequate oil to the connecting rods. The lower main shells are ungrooved to maximize oil film thickness and bearing life under high loads.

The high crush design ensures maximum retention in the bore, while the reduced overlay thickness prevents the overlay fatigue common in severe racing conditions. Extra clearance versions are available for .001" additional clearance and select fitting when needed.