Vehicle Fitment

• Honda A-Series engines (A-series applications)
• Honda B-Series engines: B17A1, B18A1, B18B1, B18C1, B18C5
• Honda K-Series engines: K20A2, K20A3, K24A (and compatible K-series variants)
• Representative vehicle applications include: 1990–2001 Acura Integra, 1994–1997 Honda Civic del Sol, 1997–2009 Honda CR-V, 1999–2011 Honda Civic, 2002–2006 Acura RSX, 2003–2012 Honda Accord, 2003–2011 Honda Element, 2004–2014 Acura TSX, 2006–2011 Acura CSX, and 2007–2012 Acura RDX

Fitment Notes

• The MB5259XPC fits Honda A-Series, B-Series, and K-Series engine blocks that share the same main bearing journal specification. Confirm your specific engine code against the compatible engine list (B17A1, B18A1, B18B1, B18C1, B18C5, K20A2, K20A3, K24A, and others) before ordering.
• Available sizes: Standard (STD) — this listing, Standard with Extra Clearance (STDX), +0.026mm, and +0.25mm. Consult your engine builder and measure your crankshaft main journals before selecting a size. For standard-dimension cranks in good condition, the STD size is typically correct.
• Sold as a complete set of 5 main bearing pairs — covers all 5 main bearing positions in Honda inline 4-cylinder engines. Upper shells are grooved (1/2 groove style) for oil distribution; lower shells are typically ungrooved.
• The "C" in MB5259XP**C** indicates the pMaxKote™ polymer top coat is applied over the pMaxBlack™ XP base — this is a 4-layer (XPC) bearing, not a standard 3-layer XP. The pMaxKote coating is factory-applied at King's facility before final dimensioning, maintaining the original wall thickness with no added coating dimension.
• Consult your engine builder to determine whether the STD or STDX size is appropriate for your specific clearance targets and crankshaft condition.

Features

• pMaxKote™ XPC four-layer construction adds a nano-composite polymer top coat over King's pMaxBlack™ XP tri-metal base — creating a bearing with both the extreme load capacity of the XP series and enhanced surface protection against the specific failure modes that affect performance Honda engines: oil starvation, surface wear, seizure, and cavitation damage
• pMaxKote™ nano-composite polymer coating contains ceramic nano-composite particles and solid lubricant distributed throughout the polymer matrix — the ceramic particles provide wear resistance, while the solid lubricant reduces friction and protects the bearing surface during periods of marginal lubrication when the oil film thickness drops below optimal levels
• Oil starvation protection is the pMaxKote's defining benefit for performance Honda applications — high-RPM builds, turbocharged engines, and track-use engines with aggressive oil surge conditions all experience momentary oil pressure drops that can damage uncoated bearings instantly. The pMaxKote coating provides a protective barrier that prevents metal-to-metal contact damage during these events
• pMaxBlack™ XP tri-metal base provides 24% stronger overlay and 17% more fatigue resistance versus conventional tri-metal race bearings through King's nano-scaled SecureBond hardening process — delivering the fundamental high-load capacity foundation that the pMaxKote coating is applied over
• Factory-applied coating with no added thickness — King applies the pMaxKote at their facility during manufacturing and dimensionally accounts for the coating layer, so the bearing ships at the correct nominal wall thickness with no additional clearance adjustment required compared to the same nominal uncoated size
• Grooved upper shells (1/2 groove style) feature enlarged, chamfered oil holes that provide improved oil delivery to the main bearing journal and through the crankshaft oil passages to the rod journals — critical for maintaining oil film integrity in high-RPM Honda engines
• BullsEye Tolerance™ at ±.0001" wall thickness ensures consistent clearance across all 5 main bearing positions — eliminating shell-to-shell clearance variation that would otherwise create uneven load distribution across the crankshaft
• XP geometric features including narrowed design and medium eccentricity provide optimum load distribution and stable hydrodynamic oil wedge formation for consistent oil film performance across the full RPM range
• Ideal for naturally aspirated and forced induction Honda/Acura engine builds targeting increased power output, extended high-RPM use, or track and competition applications

Specifications

• Part Number: MB5259XPC
• Brand: King Engine Bearings
• Bearing Type: Main (Crankshaft) Bearing Set
• Series: XPC (XP pMaxKote — 4-layer construction)
• Material Structure: Steel backing → Copper-lead intermediate → Nickel barrier → pMaxBlack™ Babbitt overlay → pMaxKote™ nano-composite polymer top coat
• Top Coat: pMaxKote™ — ceramic nano-composite particles + solid lubricant in polymer matrix
• Coating Added Thickness: None (factory-dimensioned)
• Upper Shell Groove: Yes — 1/2 Groove (grooved upper, plain lower)
• Application Engines: Honda A-Series | B-Series (B17A1, B18A1, B18B1, B18C1, B18C5) | K-Series (K20A2, K20A3, K24A)
• Size: Standard (STD)
• Quantity per Set: 5 pairs (10 shells — complete inline 4-cylinder main bearing set)
• Wall Thickness Tolerance: ±.0001"

Included Components

• 10x pMaxKote™ XPC Main Bearing Shells (5 pairs — upper grooved and lower plain — complete 5-main-journal inline 4-cylinder set)

Product Description

The King Engine Bearings MB5259XPC is the XPC (pMaxKote-coated) main bearing set for Honda A-Series, B-Series, and K-Series engines — covering the B17A1, B18A1, B18B1, B18C1, B18C5, K20A2, K20A3, K24A, and compatible engines across the Acura Integra, Honda Civic, Honda Accord, Honda CR-V, Honda Element, Acura RSX, Acura TSX, and Acura RDX. Sold as a complete set of 5 pairs (10 shells) covering all main bearing positions. Standard size — consult your engine builder and measure your crankshaft before selecting a size.

The XPC designation marks this as King's four-layer bearing: the pMaxBlack™ XP tri-metal base (steel + copper-lead + nickel barrier + hardened Babbitt overlay) is topped with King's factory-applied pMaxKote™ nano-composite polymer coating. pMaxKote adds a protective surface layer containing ceramic nano-composite particles and solid lubricant that provides the most comprehensive bearing protection available for performance Honda applications — specifically superior resistance against the oil starvation, seizure, cavitation, and surface wear that affect high-RPM, turbocharged, and track-use Honda engines where oil film consistency is intermittent under demanding conditions. The coating is factory-applied before final dimensioning at King's facility, maintaining the bearing's original wall thickness with no additional clearance adjustment required.

The XP base provides 24% stronger overlay and 17% more fatigue resistance than conventional tri-metal race bearings, while the pMaxKote adds protection specifically during the conditions where even race-quality uncoated bearings are most vulnerable — oil pressure transients, oil surge under hard cornering, and the first moments of cold-start before full oil pressure is established. BullsEye Tolerance™ at ±.0001" ensures all 5 bearing positions receive consistent clearance for uniform load distribution across the crankshaft. Grooved upper shells with enlarged, chamfered oil holes ensure optimal oil delivery throughout the Honda K-series and B-series engines' known-demanding oiling circuits.