King Engine Bearings MB556XPNCSTDX XP Series Coated Main Bearing Set

The King Engine Bearings MB556XPNCSTDX is a high-performance main bearing set designed for big block Chevrolet engines ranging from 396 to 502 cubic inches, including Gen IV, V, and VI applications. This XP Series bearing set features advanced tri-metal copper-lead construction with a hardened overlay and King's innovative pMaxBlack ceramic nano-composite polymer coating for maximum durability in demanding racing and performance applications.

Key Features:

• XP Series tri-metal copper-lead construction with hardened overlay for extreme load capacity
• pMaxBlack polymer coating enhances wear and seizure resistance without adding thickness
• Bull's Eye Tolerance: Industry-leading wall thickness tolerances with all shells matched to 0.0001 inch
• Narrowed design accommodates large-radius crankshaft fillets common in performance applications
• Standard size with .001 inch extra clearance (STDX) for optimized oil film thickness
• Half-groove upper bearing design for improved oiling
• Enlarged, chamfered oil holes for enhanced lubrication flow
• Medium eccentricity design enables optimum load distribution

Engineered specifically to withstand the extreme loads and high RPMs generated by today's competition engines, these bearings are ideal for circle track, drag racing, and other high-performance applications using steel crankshafts. The set includes five main bearings and is compatible with Chevrolet big block engines from 1965-2000, including the 396, 427, 454, and 502 cubic inch displacements.