Main Bearing Set Coated SBM 273-360

The KING BEARINGS Main Bearing Set Coated SBM 273-360 (MB 558XPC 010) is a precision-engineered bearing kit designed for small-block Mopar engines in the 273–360 cubic-inch displacement range. This 0.010-inch undersize main bearing set features KING's proprietary XP coating technology and Mopar Polysphere design, offering enhanced load capacity and extended service life in high-performance and stock engine rebuild applications.

The XP coating applied to these main bearings reduces friction and improves heat dissipation during engine operation, critical factors in both street-driven and race engines where consistent bearing clearance and durability directly impact overall engine reliability. The 0.010-inch undersize specification accommodates engines with worn crankshaft journals, allowing machinists and rebuilders to restore original bearing clearances without full crankshaft replacement. The Polysphere design distributes loads evenly across the bearing surface, maximizing oil film strength and minimizing wear under sustained RPM.

This bearing kit is essential for anyone rebuilding a Chrysler 273, 318, 340, or 360 engine—whether for restoration, performance upgrade, or daily-driver reliability. Engine builders and classic Mopar enthusiasts rely on KING BEARINGS products to meet OEM specifications while delivering the precision and consistency required for dyno-tested engine builds. The complete set ensures all main bearing positions receive matching coating and clearance specifications, eliminating inconsistencies that could compromise engine longevity.