King Engine Bearings MB5779XP0.25 XP-Series Tri-Metal Main Bearing Set Undersize - 0.25mm

The King Engine Bearings MB5779XP0.25 is an XP-Series performance main bearing set designed for extreme racing applications. This 0.25mm undersize bearing set is engineered for engines with reground crankshafts, providing the precision clearances needed for high-performance builds.

Advanced Tri-Metal Construction:

King XP-Series main bearings feature enhanced tri-metal construction with a layered copper-lead intermediate layer, nickel plate barrier, and lead-tin-copper Babbitt overlay bonded to a steel backing. This advanced adhesion process delivers superior stability, durability, and load-carrying capacity up to 17,000 psi in the intermediate layer.

Key Performance Features:

• Bulls-eye tolerance with wall thickness variation of ±0.0001 inch for unmatched precision
• Narrowed design for large-radius crankshafts
• Enlarged, chamfered oil holes for improved oil flow
• Medium eccentricity for optimum load distribution
• Hardened fatigue resistance shield for 24% stronger overlay
• Race-proven for high-load, long-duration applications

Application:

XP-Series bearings are specifically engineered for circle track racing, off-road, offshore, and other demanding applications using steel crankshafts. Ideal for high-RPM engines that require maximum durability and consistent performance under extreme conditions.

King Engine Bearings has specialized exclusively in engine bearings since 1960, using racing as the ultimate testing ground to develop bearings that excel in both competition engines and street applications.