ACL Bearings 5M5647H-STD Race Series Tri-Metal Main Bearings

ACL Race Series Main Bearings deliver the high-performance reliability demanded by serious engine builders and racing applications. These tri-metal construction bearings include both upper and lower halves, engineered specifically to withstand extreme RPM conditions and maximize engine durability.

Advanced Race-Proven Features:

• High-strength overlay plate with reduced thickness for superior fatigue resistance under extreme loads
• Hardened steel backing on all bearings to improve support of the bearing lining and enhance retention in the housing
• Increased crush design ensures optimal bearing retention and prevents spinning
• Flash plating eliminated from bearing backs to maximize heat transfer and improve grip between bearing and housing
• Increased eccentricity compensates for bore distortion at high RPM and promotes proper hydrodynamic oil film formation
• 3/4 groove design on main bearings optimizes load-carrying surface area while maintaining oil flow to connecting rod bearings
• Tight wall tolerances ensure consistent bearing clearances for precise engine assembly
• Enlarged ID chamfers on bearing edges accommodate large fillet radius found on performance crankshafts

The unique combination of advanced metallurgy, precision engineering, and race-proven design makes ACL Race Series bearings the choice of professional engine builders and performance enthusiasts worldwide.