Clevite MS-1117P-.50MM High Performance Main Bearing Set -0.50mm Undersize

The Clevite MS-1117P-.50MM is a high-performance main bearing set designed for demanding racing and performance engine applications. This P-Series bearing set features 0.50mm undersize dimensions for use with reground crankshafts, providing precise fitment and optimal clearances for rebuilt performance engines.

P-Series Performance Features:

• High crush design for maximum bearing retention under extreme loads
• Reduced overlay thickness to prevent overlay fatigue and "hen tracking"
• Full groove upper shells to maximize oil flow to connecting rod bearings
• Hardened steel backing for added strength and fretting resistance
• Maximum eccentricity design to narrow bearing contact patterns and prevent rod bearing oil starvation
• Engineered for extremely high RPM applications where severe rod bore close-in occurs

When to Use P-Series Bearings:

P-Series main bearings are ideal for high-RPM racing engines experiencing severe rod bore distortion, typically indicated by nearly full parting-line contact patterns. The higher eccentricity design narrows bearing contact patterns while ensuring adequate oil delivery to rod bearings, preventing the polishing, smearing, and discoloration caused by rod bearing oil starvation.

Technical Design:

These main bearings utilize Clevite's proven TriMetal construction with a 180-degree groove in the upper shell—extensively tested to provide the best overall performance for racing applications. The upper shell groove supplies oil to connecting rods while the ungrooved lower shell maintains maximum oil film thickness for superior load capacity and bearing life. This design delivers lower horsepower loss and reduced peak oil film pressure compared to full-grooved or extended-groove designs.

Designed for professional engine builders and serious racers who demand maximum durability under extreme conditions.