Clevite MS-704P Engine Crankshaft Main Bearing Set

The Clevite MS-704P is a high-performance engine crankshaft main bearing set designed for precision engine builds. This bearing set features Clevite's proven TriMetal construction, providing exceptional strength and durability for demanding applications.

Understanding Main Bearing Design:

Modern main bearing technology focuses on optimizing oil film thickness for maximum bearing life. This set utilizes an engineered 180-degree groove in the upper shell to supply oil to connecting rod bearings while maintaining ungrooved lower shells. The lower shells develop a thicker oil film for the crankshaft to ride on, providing superior load capacity and extended bearing life. Extending grooves into the lower bearing half reduces oil film pressure and increases friction losses without providing performance benefits.

P-Series Performance Features:

• High eccentricity design for optimized load distribution
• Full groove configuration for maximum oil flow to rod bearings
• High crush construction for superior bearing retention
• Reduced overlay thickness to prevent overlay fatigue
• Hardened steel backing for added strength and fretting resistance
• Ideal for applications requiring increased oil delivery to connecting rod bearings

When to Use P-Series Bearings:

P-Series main bearings are recommended for high-RPM engines where rod bearing oil starvation is a concern, typically indicated by polishing, smearing, or discoloration at the bearing center. The higher eccentricity narrows contact patterns and increases oil flow to rod bearings. These bearings work best in engines experiencing extreme RPM-induced connecting rod bore distortion.

Clevite Performance Bearing Series Comparison:

Clevite offers multiple performance bearing series to match specific engine requirements. P-Series bearings feature the highest eccentricity with full grooving for maximum oiling. H-Series bearings provide medium eccentricity with enlarged chamfers for oversize crankshaft fillets. K-Series bearings add TriArmor moly/graphite coating for enhanced protection. V-Series bearings utilize lead-indium overlay for superior conformability. M-Series micro bearings feature thick babbitt lining for extreme crankshaft deflection conditions.

Contact patterns should ideally cover two-thirds to three-quarters of the bearing surface. Select bearing series based on your specific engine requirements, RPM range, and crankshaft specifications.