ACL Bearings 5M1959H-.025 Race Series Main Bearing Set 0.025mm Oversize

The ACL Race Series 5M1959H-.025 main bearing set is an oversized high-performance trimetal bearing designed for Honda and Acura B-series and K-series engines. This 0.025mm oversize bearing is engineered for racing and high-performance applications where increased bearing capacity and durability are essential.

Key Features:

• Trimetal construction with high-strength overlay plate and reduced thickness for improved fatigue properties
• Hardened steel backing on all bearings to improve support and assist with bearing retention in the housing
• Designed to withstand higher RPM conditions common in performance builds
• Increased crush for improved bearing retention under extreme conditions
• Elimination of flash plating on bearing backs to maximize heat transfer and improve grip in housing
• Increased eccentricity to compensate for bore distortion at high RPM and assist in oil film formation
• 3/4 grooved design optimizes bearing load carrying surface area and oil flow to connecting rod bearings
• Enlarged ID chamfers on bearing edges to accommodate large fillet radius on performance crankshafts
• Precision manufactured to micron tolerances for consistent wall thickness and crush characteristics

Compatibility: Honda B16A, B17A1, B18A1, B18B1, B18C1, B18C5, B20B, B20Z and Acura K20A2, K20A3, K24A engines. The 0.025mm oversize dimension is equivalent to a Honda green bearing with an additional 0.025mm of thickness.

Technical Specifications: Maximum shaft size 2.1654 inches (55mm), minimum shaft size 2.1646 inches (54.98mm), maximum tunnel size 2.3236 inches (59.02mm), maximum wall thickness at crown 0.0788 inches (2.002mm), overall length 0.7874 inches (20mm).