ACL Race Series Main Bearing Set: Holden 186 (0.020" Undersize)
Part Number: 7M2384H-020
Application: Holden Red Series (138, 149, 161, 179, 186)
Product Overview
The ACL Race Series Main Bearing Set (7M2384H-020) is engineered specifically for the Holden "Red" engine family. This set is designed for crankshafts that have been precision-ground by 0.020 inches (0.508mm). These bearings offer the same high-performance tri-metal durability as the standard race series, ensuring longevity for rebuilt engines.
Understanding the Part Number
7M: Indicates Main Bearing set.
2384: The base engineering designation for the Holden 6-cylinder series.
H-020: Indicates standard oil clearance for a crankshaft journal that has been ground down by 0.020".
Fitment Summary
Compatible with all Holden Inline-6 (OHV) Red Motors, including: 138ci, 149ci, 161ci, 179ci, and 186ci engines.
Technical Specifications
Max Tunnel Size: 60.721 – 60.747 mm (2.3906 – 2.3916 in)
Max Shaft Size: 55.316 – 55.341 mm (2.1778 – 2.1788 in)
Wall at Crown (Max): 2.677 mm (0.1054 in)
Why Choose the Race Series?
Unlike standard replacements, the ACL Race Series utilizes a robust Tri-Metal composition designed to handle high-RPM heat and mechanical stress without distortion. Key enhancements include increased crush for better retention, increased eccentricity for oil film stability, and large fillet radii compatibility.
Disclaimer: Always verify clearances using a bore gauge and micrometer during assembly. This part is intended for crankshafts professionally machined to 0.020" undersize specifications.
