King Engine Bearings CR6640XPC0.25 Connecting Rod Bearing Set 0.25mm Undersize XPC pMaxKote Race Series

The King Engine Bearings CR6640XPC0.25 is a 0.25mm undersize XPC Race Series connecting rod bearing set engineered for BMW M20 and M50 engines displacing 2.0L, 2.5L, and 2.7L. This set includes 6 pairs of tri-metal performance bearings built to handle the elevated loads and RPM demands of high-performance and racing applications.

The XPC designation represents King's top-tier race bearing technology, combining the pMaxBlack™ tri-metal overlay with a factory-applied pMaxKote™ nano-composite polymer coating. pMaxBlack™ uses a surface-hardened lead-tin-copper overlay electroplated onto a copper alloy substrate, with 5% copper content and a proprietary nano-scaled hardening process delivering a load capacity of up to 10,200 psi — significantly greater than conventional performance bearings. The pMaxKote™ polymer coating is then applied over the pMaxBlack™ layer at the King factory, adding a ceramic nano-composite fourth layer that enhances wear and cavitation resistance and protects bearing surfaces during periods of marginal lubrication — all without adding any wall thickness or altering oil clearances.

Key Features:

• XPC Race Series — tri-metal copper-based construction with pMaxBlack™ overlay and pMaxKote™ polymer coating
• pMaxBlack™ overlay — 5% copper content with nano-scaled hardening process; up to 10,200 psi load capacity
• pMaxKote™ coating — factory-applied ceramic nano-composite polymer coating for superior wear and cavitation resistance
• No added thickness — pMaxKote™ applied with no change to precision wall thickness dimension, preserving oil clearances
• RadiaLock™ — computerized simulation-optimized crush height ensures ideal radial pressure and reduces risk of spun bearing
• SecureBond™ — micro-etch surface preparation strengthens tri-metal structural integrity against delamination under extreme loads
• 0.25mm undersize — for use with reground crankshafts machined to 0.25mm undersize journals
• Set includes 6 pairs of connecting rod bearings
• Suitable for circle track, drag racing, offshore, and other performance applications utilizing steel crankshafts

King Engine Bearings has specialized in precision engine bearings since 1960, and the XPC pMaxKote series represents the pinnacle of their race bearing technology — delivering unmatched durability and load capacity for built BMW inline-six engines.