ACL Bearings 5M8138-STD Standard Main Bearing Set

The ACL Bearings 5M8138-STD is a standard size crankshaft main bearing set engineered for high-performance and racing applications. As part of ACL's Race Series lineup, this bearing set delivers the precision, durability, and reliability demanded by serious engine builders and motorsports professionals.

Key Features:

• Tri-metal copper alloy construction blends high strength with excellent seizure resistance
• Manufactured to exact tolerances ensuring reliable fit and consistent oil clearances
• Increased crush design improves bearing retention and stability during operation
• Hardened steel backing provides superior support for the bearing lining
• Enlarged inner diameter chamfers accommodate large fillet radii on performance crankshafts
• Extended oil grooves optimize lubrication distribution throughout the bearing surface
• No flash plating on bearing backs improves heat transfer and maximizes grip in housing

ACL Race Series bearings are trusted by championship-winning race teams across multiple disciplines including drag racing, drift, rally, and road racing. With over 70 years of manufacturing expertise and ISO-certified processes, ACL delivers bearings that provide the endurance and capability to perform where others cannot. Standard size ("-STD") bearings are designed for use with unmodified crankshaft journals.