Engine Bearings Racing Main Bearings

The King Engine Bearings MB4058XP is part of the XP Tri-Metal Racing Series, developed to meet the extreme performance demands of modern race engines. This series is ideal for high-load, long-duration racing applications such as circle track, off-road, and off-shore racing, particularly those utilizing forged steel aftermarket crankshafts. These performance main bearings feature an advanced tri-metal construction with pMax Black technology, a proprietary material that is 24% harder than conventional tri-metal race bearings. The construction includes a copper-lead composition with a nickel barrier and SecureBond adhesion, ensuring superior stability between the top and intermediate layers. A 0.0005" metallurgically enhanced and hardened performance overlay is integrated to withstand greater loads and resist surface fatigue. Key features of the MB4058XP bearings include a 15% - 30% increase in load capacity over traditional bearings. The main shells are designed with a 1/2 groove to maintain uncompromised lower shell load capacity.