King Engine Bearings CR4604XP.026 XP Rod Bearing Set +0.026mm Mazda L3-VDT Ford

Vehicle Fitment

• 2007-2013 Mazdaspeed 3 (L3-VDT MZR DISI 2.3L Turbo)
• 2006-2007 Mazdaspeed 6 (L3-VDT MZR DISI 2.3L Turbo)
• 2007-2012 Mazda CX-7 (L3-VDT MZR DISI 2.3L Turbo)
• Ford 2.3L Duratec / EcoBoost applications sharing the same 52mm rod journal specification

Fitment Notes

• The CR4604XP.026 is the +0.026mm oversize variant - for use when the connecting rod journals on the crankshaft have been ground 0.026mm undersize during machining. This is not the same as the STDX (extra clearance) variant. Verify your crankshaft journal dimensions before ordering to confirm the correct size is required.
• Available sizes for the CR4604XP series: Standard (STD), Standard with Extra Clearance (STDX), +0.026mm Oversize (this part), +0.25mm Oversize, and +0.50mm Oversize. Select based on measured crankshaft journal diameter. Consult your engine builder before ordering.
• Sold as a complete set of 4 pairs (8 shells) - covers all 4 connecting rods in the L3-VDT or 2.3L Duratec 4-cylinder engine.
• The CR4604XP series applies to the L3-VDT MZR DISI turbocharged 2.3L engine and the Ford 2.3L Duratec/EcoBoost family sharing the 52mm rod journal dimension. Verify the journal diameter of your specific engine before ordering to confirm CR4604XP compatibility.
• King's factory-applied pMaxBlack™ overlay maintains original wall thickness - the nano-scaled hardening process does not add measurable thickness to the bearing shell, so clearance calculations remain standard for the selected nominal size.

Features

• pMaxBlack™ tri-metal overlay - King's proprietary nano-scaled hardening process modifies the molecular structure of the Babbitt overlay, creating a black fatigue-resistant shield that is 24% stronger and provides 17% more fatigue resistance than conventional tri-metal racing bearings
• SecureBond adhesion process bonds the copper-lead intermediate layer, nickel barrier, and Babbitt overlay to the steel backing with superior adhesion stability - preventing overlay separation and delamination under the extreme shear forces generated by high-boost, high-RPM turbocharged applications
• 10,200 PSI load capacity significantly exceeds the demand placed by modified L3-VDT and 2.3L EcoBoost applications - providing a meaningful safety margin for highly boosted builds, track use, and competition applications where bearing loads are amplified beyond OEM specifications
• XP geometric features include a narrowed design on the crank cheek side and increased crush height - the narrowed design increases bearing-to-bore contact area and improves heat transfer out of the bearing shell, while increased crush height ensures the shell seats correctly and resists spinning in the connecting rod bore at high RPM
• BullsEye Tolerance™ - King maintains wall thickness tolerances of ±.0001" shell-to-shell, far tighter than industry standard, ensuring the most precise and consistent clearance relationship between bearing and journal across all 8 shells in the set
• Medium eccentricity design enables optimum load distribution across the bearing surface and improved oil film consistency throughout the journal's rotation
• Chamfered oil holes (on main variants) and optimized oiling geometry ensure consistent oil delivery to the bearing surface under demanding conditions
• Ideal for all performance applications including circle track, drag racing, off-shore, and road course use - particularly suited for engines running forged steel aftermarket crankshafts that produce high loads over extended periods

Specifications

• Part Number: CR4604XP.026
• Brand: King Engine Bearings
• Bearing Type: Connecting Rod (Big End) Bearing Set
• Series: XP (Xtreme Performance)
• Material: pMaxBlack™ Tri-Metal (Steel backing → Copper-lead layer → Nickel barrier → Babbitt overlay with nano-scaled hardening)
• Overlay Load Capacity: 10,200 PSI
• Overlay Strength vs. Conventional: 24% stronger
• Fatigue Resistance vs. Conventional: 17% improvement
• Wall Thickness Tolerance: ±.0001"
• Size: +0.026mm Oversize (for crankshaft ground 0.026mm undersize)
• Rod Journal Diameter: 52mm
• Application Engines: Mazda L3-VDT MZR DISI Turbo 2.3L | Ford 2.3L Duratec/EcoBoost (52mm journal)
• Quantity per Set: 8 shells (4 pairs - complete 4-cylinder engine)
• Design Features: XP Narrowed Width | Increased Crush Height | BullsEye Tolerance™ | Medium Eccentricity

Included Components

• 8x pMaxBlack™ XP Connecting Rod Bearing Shells (4 pairs - complete 4-cylinder set in +0.026mm oversize)

Product Description

The King Engine Bearings CR4604XP.026 is the XP-series connecting rod bearing set for the Mazda L3-VDT MZR DISI turbocharged 2.3L engine and Ford 2.3L Duratec/EcoBoost applications sharing the 52mm rod journal specification, in the +0.026mm oversize for use with crankshafts ground 0.026mm undersize. The set includes 8 shells (4 pairs) covering all four connecting rods in the engine. Consult your engine builder and measure the crankshaft rod journals before ordering to confirm the +0.026mm size is correct for your specific application.

The XP-series is King's performance rod bearing specification for high-load, extended-duration race and street/strip applications. The pMaxBlack™ overlay uses King's proprietary SecureBond nano-scaled hardening process - the same fundamental technology that makes King bearings the choice of top racing teams worldwide - to deliver a Babbitt surface that is 24% stronger and 17% more fatigue-resistant than conventional race tri-metal bearings. This is directly relevant for L3-VDT builds running elevated boost, forged internals, and aggressive tune maps, where stock-grade bearings fail predictably under sustained high cylinder pressure and oil pressure fluctuation at high RPM.

The XP geometric package adds to this material advantage: the narrowed crank-cheek-side design increases bearing contact area and improves heat transfer out of the shell, while the increased crush height ensures the shell is correctly seated and mechanically locked in the bore even under high shear loads at peak RPM. BullsEye Tolerance™ at ±.0001" wall thickness provides the most consistent clearance relationship in the industry, shell-to-shell. Verify your crankshaft journal dimensions against a standard micrometer before ordering - the .026 size designation refers specifically to a crankshaft ground 0.026mm undersize, not a clearance preference.