ACL Bearings 5M8297H-STD Race Series Main Bearing Set for Subaru EJ Engines

The ACL Bearings 5M8297H-STD Race Series Main Bearing Set is engineered for high-performance Subaru EJ-series engines, including the EJ15, EJ16, EJ18, EJ20, EJ22, and EJ25 (including turbocharged variants). This complete main bearing kit features thrust bearing positioned at journal #3, making it compatible with specific WRX and STI engine configurations. ACL Race Series bearings are trusted components in championship-winning engines across motorsports disciplines from drift racing to NHRA competition.

Trimetal Construction & Performance Features:

• High-performance trimetal design featuring three layers: hardened steel backing, copper-lead intermediate layer, and nickel overlay for superior strength and lubrication
• High-strength overlay plate with reduced thickness for improved fatigue resistance
• Hardened steel backs for enhanced bearing support and retention in the housing
• Increased crush design for improved bearing retention and heat dissipation
• Elimination of flash plating on backing to maximize heat transfer and grip
• 3/4 grooved main bearings optimizing load carrying surface area and oil flow to connecting rod bearings
• Increased eccentricity to compensate for bore distortion at high RPM and assist in hydrodynamic oil film formation
• Precision manufacturing to exacting tolerances for consistent wall thickness and reliable clearances

Specifications:

• Size: Standard (STD) - precision finished for nominal clearance based on OEM specifications
• Thrust Position: Journal #3
• Application: Subaru EJ-series engines (1.5L through 2.5L)
• Construction: Trimetal (steel, copper-lead, nickel)

Designed to withstand higher RPM conditions and extreme loads, ACL Race Series bearings offer an excellent balance of strength and forgiveness. They perform equally well in street-driven performance vehicles and dedicated race applications. Suitable for all engine builds using crankshafts finished to OEM specifications.