RB - 2.750" , B - 2.625
1958 up until the 1973 ,the diameter of the thrust surface's is 3.470-B , 3.600 - RB engine.
1974 the diameter of the thrust surface's is 3.750 - B engine, 3.880 - RB .
1, 2, 4 & 5 are the same for all years.
Some Racing cranks and blocks use 3" Mains, and these require a separate thrust bearing (Kit - 4 pieces), there is 2 different kits :
Aluminum (aftermarket ) =
Stock blocks that have been align bored to 3" =
are the original staple bearing. Recommended for stock rebuilds up to medium performance use, these tri metal bearings are made from TM-77 material. They start with a hardened steel back for strength and support. Over that is a cast copper lead lining to provide the durability and support to withstand the loads of engine operation. Then a nickel plating is applied to prevent interaction between the copper lead and the final layer, a strong, extra thin (.001 or less) electroplated overlay of babbitt. Babbitt is a tin or lead based alloy with varying amounts of antimony, copper or arsenic which is designed to resist flaking and is very soft by nature. This helps to give the bearing embedability (the ability for stray particles to be absorbed by the bearing so they don't rip the crank journal to shreds), conformability (the ability of the bearing to conform or adapt to any out of spec surfaces or distortion) and resistance to both seizure and corrosion while still withstanding the high loads a performance engine can generate. Finally they are flash plated with a lead/tin mixture to help protect them and mostly make them look better, (yes this step is mostly cosmetic.) These bearings have high crush for better retention and their high eccentricity helps to accommodate any housing bore distortion. These are a good quality line of bearings, however if you are building an engine that is highly modified, such as aftermarket cylinder heads, etc, you will probably want to think about upgrading to one of the performance bearings listed below. P series are not clearanced for aftermarket cranks with larger crankshaft fillets, although they will usually still work correctly, and any competent shop should be able to easily perform this operation to them if needed.
Originally developed for Nascar racing, H series are made of the same TM-77 material as the P series, and include most of the features described above, however they are not flash plated with the lead/tin apparently in an effort to help them seat better. They also have enlarged chamfers to help them clear bigger crankshaft fillets. In rod bearings, these are available in .001 oversize, standard (.000) and .001 undersize, making them an ideal choice for those who want more flexibility in setting their clearances. They also have a medium level of eccentricity. A good overall performance bearing, especially if you need the precision sizes.
Part numbering is based on the same core number as the high performance part and will service the same application. These bearings were developed primarily for high performance applications and all types of competition engines. K-Series bearings have a proprietary moly/graphite treatment applied to the bearings surface, but not the bearing parting lines. The PTFE carrier material gives good low load start-up protection. The moly serves as a high pressure, high load dry film anti-wear agent. Graphite provides additional protection across the broad range of temperatures, especially when oil flow is marginal and is especially slippery with an oil film. These bearings, which are also referred to as TriArmor, still offer the strength and durability of the legendary Clevite TriMetal bearing construction coupled with the latest in coating technology.
M stands for Micro Babbitt, and these bearings are made of Clevite's B-2 material. This consists of a hardened steel backing, to which a .006 thick layer of babitt material is bonded. Because babbitt is very soft, these bearings have an outstanding level of conformability, (the ability of the bearing to conform or adapt to any out of spec surfaces or distortion) for applications where the crankshaft may be subjected to severe deflection under load. However, the downside of this is that the life of these bearings can be very short, and these are generally considered a race only item. Although some engine builders are familiar with and prefer this style of bearing, it is generally accepted that the V series will do just as good a job without the short lifespan, making the M series in our opinion, not the best choice for all but the most specialized of applications.
The V series were originally manufactured by the Vandervell company in England, Clevite bought Vandervell and is now distributing their bearings under the Clevite name as the V series. We feel the V series are a great choice for performance bearings. V series have found their way into nearly every form of motorsports with virtually no problems. Nearly 100% of 8000+ horsepower top fuel drag racing teams use them. They are almost universally used in Pro Stock and Winston Cup. Cosworth Formula one engines that turn 11,000 RPM for extended periods of time use them with great success. These bearings are still a tri metal bearing, however they use a lead indium overlay instead of the babitt in the above bearings. Lead Indium has amazing properties. It has a super low surface friction coefficient or lubricity, meaning wear at startup before the engine can develop oil pressure is greatly reduced. It can withstand and operate at higher temperatures for longer periods of time. It will resist flaking and peeling under extreme loads better than any other bearing. It has the highest resistance to corrosion of any bearing material, and it does all this while still having unsurpassed properties of embeddability, conformability and fatigue strength. And the best part is just because these perform so exceptionally in a racing environment, there is no reason they can't be used with equal success in a street car or in milder performance engines as well. These have a low to medium level of eccentricity, and also are usually narrowed to help them clear bigger crankshaft fillets. .