King Engine Bearings, a leading manufacturer of cutting-edge engine bearings since 1960, developed the King Racing line to improve engine bearing performance under extreme conditions. King Racing combines innovative research and development processes and rigorous lab tests with "on- track" trials conducted by selected racers.
The King Racing line combines sport compact and domestic race engine bearings with ground-breaking geometrical and metallurgical features. 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 we met the challenge with the XP high performance bearings series.
The Science of Speed
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
Typical race bearings are manufactured to meet the industry’s traditional +/- 0.00025 ” wall thickness tolerance. But race engine builders often prefer narrow, more specific oil clearances with far more tolerance control.
To achieve the right clearance, they compensate for bearing thickness inconsistencies by grinding cranks “fat” or “thin”, adjusting the housing bore, or purchasing multiple sets to “fish” for shells. The process is time consuming, costly and tedious.
King listened to its engine building customers and responded with Bull’s Eye Tolerance™, which is a production technology developed by King. It combines highly accurate machining, overplating, and computerized wall thickness monitoring that adjusts the process on-the-spot.
Bull’s Eye Tolerance™ outperforms the industry’s wall thickness tolerance, ensuring the least thickness variation shell-to-shell. The outcome: A new standard in bearing thickness consistency.
- 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
pMax-Black™ combines a unique tri-metal structure with advanced surface processes to deliver superior load capacity.
The intermediate layer of a typical race bearing contains 2-3% tin, with hardness values of 90-95 HV. Within the pMax Black™ intermediate layer, we increased the tin content to 4.5%, making it 22% harder at 115 HV, with a load carrying capacity of 17000 psi.
The overlay of a typical high performance bearing features a leaded alloy that contains 2-3% copper content. The bearing ‘reaches a hardness level of 11-11.5 HV, and a maximum fatigue resistance at 8000-8500 psi.
- 24% greater load capacity
- 17% more fatigue resistance
- Compatible with all crankshafts
Sold in a full set of STANDARD sized bearings. If oversized bearings are required please contact us via phone or the product questions below.
**Suitable for all RB25DE(T) and RB26DE(TT) engine builds!**