King Bearings — Engine Bearing specialist


  1. How King’s pMAX Black material can affect the journal surface?

    There is absolutely no effect or damage causes by Pmax Black to the journal surface.
    Pmax black bearings differ from the competitive bearings due to a special surface treatment of the overlay. The treatment produces a strong ultrathin (nano-scale) skin which inhibits formation of fatigue cracks. Therefore load capacity of Pmax black bearings is at least 17% greater than that in the competitive racing car bearings. Hardness of Pmax black overlay is also higher than that of the competitive overlays (by 24%).
    The value of hardness 18 HV in comparison to 11-14HV of competitors is still low enough to provide excellent anti-friction properties of the bearings (embedability, conformability and compatibility). For example hardness of aluminum alloy in bi-metal bearings is about 40HV.
    The extremely low (nano scale) thickness of the hardened surface layer of Pmax black bearings guarantees that the journal surface can not be damaged (scratched) during metal-to-metal contact. If direct friction occurs the surface shield wears off from the overlay surface producing no scratches on the steel surface.
    The effect of direct friction between tri-metal bearings (surface hardened and non-treated) and steel journals has been tested in King Test Rigs. The results proved total indifference in regards of the journal surface damage between the treated (Pmax black) and non-treated bearings.

  2. How much clearance should my bearings have?

    In order for bearings to maintain a stable oil film, which is vital to their life, there must be a perfect match with clearance size, oil viscosity, engine operating  temp, crank surface finish and geometrical alignments. General rule of thumb for determining oil clearance is .001 of clearance for every inch of shaft dia. Ex .001 x 2.00 shaft dia.  = .002 oil clearance.  For clearances smaller and larger than the rule of thumb ,refer to the factors listed below:

    Factors for tighter oil clearances:

    • Smaller journals
    • Lower viscosity oils
    • Surface finishes min 4 RA
    • Near perfect crank and engine block geometry
    • Higher engine operating temperature  due to decreased oil flow
    • Perfectly balanced cranks

    Factors for looser oil clearances:

    • Larger journals
    • Higher viscosity oils
    • Surface finishes rougher than 5 RA
    • Not so perfect crank and engine block geometry
    • Lower engine operating temp due to increased oil flow
    • Weaker housing bores causing distortion at high RPM’s

    Engine bearings should operate with the least amount of oil clearance as possible. Tighter oil clearances produce less peak loading on the bearings and the engine runs smoother with less vibration. Remember, you can mix bearing sizes offered by King to achieve desired oil clearances. Ex. Pair a STD half bearing with either a .001 or STDX half bearing to obtain your clearance. Read more about optimization of clearance

  3. When should I use HP or XP bearings?

    HP Bi Metal aluminum bearings are best suited for street/strip, all out drag racing, monster truck and medium loaded  circle track racing engines . HP’s have great embedability and conformablility characteristics  for absorbing  debris and conforming to crankshaft deflection. They also work very well with nodular stock type and steel crankshafts. The high silicon content in the aluminum alloy helps keep the ferrite cavities rounded off to prevent excessive bearing wear.

    XP pMax Black Tri-Metal bearings are best suited for very high loads for extended periods of time such as circle track, off shore boat, and off road racing. Their load rating is more than 2000 psi higher than the HP bearings and are compatible with all types of steel crankshafts.

  4. What is pMax Black?

    pMax Black is a unique tri-metal structure the has been developed to meet the ongoing demand for bearings with increased load capacity. As engines evolve and gain more power, engine bearings have to be able to handle the extra loading.

    pMax Black consists of three layers that come together to form the strongest tri-metal bearing in the industry with load capacity exceeding the competition by as much as 24%. King Racing’s new hardening technology modifies the overlay molecular structure and creates a fatigue resisting shield.

  5. What is the difference between intermediate load capacity and overlay load capacity in Tri-Metal bearings?

    Intermediate layer load capacity is the load capacity of the bronze second layer of tri-metal engine bearings. Overlay capacity is the load capacity of the top third layer of a tri-metal bearing like CP & XP. However, the fatigue life of the tri-metal bearing will be determined by the load capacity of the overlay.

  6. What is the King Racing line?

    King 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. King’s Racing line combines sport compact and domestic race engine bearings with ground-breaking  geometrical and metallurgical features. To learn more visit King Racing website

  7. Does King have bearings that work with large fillet aftermarket crankshafts?

    Yes, in racing applications, King has narrowed bearings to clear large fillet aftermarket crankshafts. The letter N as part of the part number is an indication of this feature.

  8. Just how accurate are King’s bearing wall sizes?

    King’s Bulls Eye Tolerance is a production technology that 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.. Better accuracy means less time fitting bearings to achieve desired oil clearances and less bearing sets on hand.

  9. How complete is the application coverage with King Bearings?

    King Engine Bearings has the widest range of applications and undersizes for automotive and light truck OE replacement bearings as well as  sport compact & domestic high performance racing bearings.

  10. Does King have bearings that work with crankshaft thrust and housing bore repairs?

    Yes, in limited applications, King offers its customers oversized thrust length and oversized housing bore bearings to do these repairs. Oversizes are listed in both the E-Catalog and the paper bound master catalog under each application section.

  11. What do I need to do to the bearing before I install in the housing?

    After removing the plastic film that surrounds the bearings, simply wash them with a solvent and wipe dry with a clean lint free cloth.  Make sure there is no debris on either the bearing steel back side or the bearing surface.  King bearings are spayed with light oil during manufacturing to prevent any corrosion during storage and transportation.  Do not attempt to use any abrasive  material on the bearing surfaces. Overlays and lining materials are softer layers that can be damaged reducing their thickness. King bearings installation guidline

  12. Does King have coated bearings?

    Yes, King has developed it own proprietary polymer coating for applications that need extra anti-friction properties due to low viscosity oils and very tight oil clearances. These coatings are also a requirement for low rpm start/stop engines. Read more about King surface treatments

    During 2016, King developed a new coating for race bearings called pMaxKote™. Read more about King Polymer bearings

  13. Does King produce any lead free bearings?

    Yes, King has developed both lead free bi-metal and lead free  tri-metal bearings to satisfy both OE and environmental demands.

  14. What is the highest load rated bearing that King has to offer?

    King makes a bearing material that is lead free and has a load capacity of over  18,000 psi . It has a sputter deposited  (PVD, Physical Vapor Disposition)  overlay that withstands very high loads from direct injection diesel  and turbo charged engines. This product has been tested and found to be the strongest bearing available. King’s lead free materials

  15. Does King make all of its products or do they get bearings from other sources?

    King Engine Bearings manufactures all of our half shell rod and main bearings.

    This is all done under one roof so the quality can be maintained to King’s high standards.

    In fact, King actually designs and manufactures its own machinery and equipment for  production of its products.  This way bearings can be made more efficiently and at lower costs. Read about King self designed production line

We are bearing specialists. King Engine Bearings was founded in 1960 with one simple objective: to supply the highest quality bearings available in the marketplace. By specializing in engine bearings, King has built an extensive product offering that includes a wide range of engine bearings for automobiles, light duty and heavy duty trucks, marine, aviation, standby power and many other types of internal combustion engines. Every King bearing utilizes the highest quality materials and the most advanced designs to ensure complete customer satisfaction.