The ACL 5M8309HC-.25 is a Race Series main bearing set with a coated bearing surface, machined .25mm undersize for a crankshaft main journal that has been machined undersize during an engine rebuild. It is built for Subaru EJ20/EJ22/EJ25 applications.
Specifications:
- Type: Main Bearing Set (Coated)
- Series: Race Series
- Size: 0.25 mm Undersize
- Engine Fitment: Subaru EJ20/EJ22/EJ25
- Part Number: 5M8309HC-.25
FAQ
What engine does the ACL 5M8309HC-.25 fit?
The ACL 5M8309HC-.25 is designed for Subaru EJ20/EJ22/EJ25 applications.
What does the ".25mm Undersize" designation mean?
It means the bearing is machined to match a crankshaft main journal that has been machined .25mm undersize during an engine rebuild or regrind.
Is this bearing set coated?
Yes. The ACL 5M8309HC-.25 features a coated bearing surface, per ACL's part designation for this SKU.

