ACL Bearings 4B4390HX-STD Race Series Rod Bearing Set for Mazda 2.0L MZR

The ACL Bearings 4B4390HX-STD is a high-performance connecting rod bearing set designed specifically for Mazda 2.0L LF MZR engines, including the Mazda3 and MX-5. Part of the acclaimed Race Series lineup, these bearings are engineered to deliver championship-level performance in demanding motorsports applications.

Race-Proven Performance:

ACL Race Series bearings are standard components in race engines that have set records and won championships across multiple disciplines, from sport compact drift racing to NASCAR, IHRA, and NHRA competitions. The unique combination of advanced design, specialized metallurgy, and precision engineering provides these bearings with the endurance and capability to perform where others cannot.

Key Features:

• Tri-metal construction with hardened steel backing for maximum durability
• Standard size with 0.001" extra oil clearance (HX designation) for improved lubrication
• High strength overlay plating with reduced thickness for improved fatigue properties
• Increased crush for superior bearing retention in the housing
• Enhanced eccentricity to compensate for bore distortion at high RPM
• Tight wall tolerances for consistent bearing clearances
• Elimination of flash plating on bearing backs for improved heat transfer
• Complete set includes 8 bearing halves (identical halves)

Applications:

This bearing set is designed for Mazda 2.0L LF MZR (Duratec) engines found in the Mazda3 and MX-5. The HX suffix indicates this is a standard journal size bearing with 0.001" additional oil clearance, making it ideal for high-performance and racing applications where increased oil flow is beneficial.

Built to withstand high RPM conditions, extreme stress loads, and elevated operating temperatures, ACL Race Series bearings deliver the reliability and performance demanded by professional engine builders and serious enthusiasts worldwide.