XP-Series Main Bearing Set (MB4104XP) by King Engine Bearings®. Bearing Size: Standard. Quantity of pairs in set: 4. pMax Black™ is a unique tri-metal structure for race applications. The overlay is strengthened by a proprietary nano-scaled hardening process that modifies the molecular structure and creates a black fatigue-resistant shield.

Specifications:

Bearing Usage: Performance
Grooved Bearing: Yes
Groove Location: Upper
Groove Style: Full
Bearing Material: Tri-metal copper-lead nickel
Lining: Cu21Pb4.5Sn
Overlay: Pb10Sn5Cu surface hardened


Features:

No more multiple set purchases or "fishing" for bearings to reach right clearance
No need to grind cranks "fat" or "thin"
No need to adjust housing diameter
Less taper across the bearing face
Better load distribution across the bearing surface
A more stable hydrodynamic lubrication regime
Greater bearing durability at high RPM's
Increases oil passage capacity
Produces higher oil supply reliability
No need for custom-made oil hole enlargement
Optimal press fit
Improves bearing spin and fretting prevention
Better heat transfer
Reduces bearing and housing distortion
Better oil wedge formation
Stable hydrodynamic lubrication regime
Minimized vibration and wear
Prevention of oil film "wiping" in high RPM conditions
Optimal load distribution across bearing surface


Successful race engine builders are constantly pushing the limits of load capacity to new levels. Race bearings today inevitably need to match these demands with more competitive bearings. At King Racing they met the challenge with the XP high performance bearings series.

The XP series is a line of bearings with advanced metallurgical and geometric technologies that meet extreme performance loads. It was developed for all performance applications that use forged steel aftermarket crankshafts and produce high loads for extended periods.

King Racing’s XP series features pMax Black™, a unique tri-metal structure that is 24% harder than any other conventional tri-metal race bearing. pMax Black™ together with the XP geometric features are the ideal combination for performance racing.