This ACL High Performance main bearing set is sized 0.25mm (0.010") over standard for the Mitsubishi 4G63/4G64 7-bolt turbocharged inline-4, used in the Lancer Evolution V-IX. The 0.25mm oversize is for a crankshaft journal that has been reground down to that undersize spec — not for a stock, unmachined crank.
Specifications:
- Type: Main Bearing Set
- Series: High Performance
- Size: 0.25mm (0.010") Oversized
- Engine Fitment: Mitsubishi 4G63/4G64 7-Bolt Turbo Inline-4
- Vehicle Platform: Mitsubishi Lancer Evolution V-IX
- Part Number: 5M1219H-.25
FAQ
What does the 0.25mm oversize mean?
It means the bearing shell is 0.25mm (0.010") thicker than standard, sized for a crankshaft journal that has been reground down to that undersize — it is not for a stock, unmachined crank.
What engine does this main bearing set fit?
It's designed for the Mitsubishi 4G63/4G64 7-bolt turbocharged inline-4 used in the Lancer Evolution V-IX.
Is this a High Performance series bearing?
Yes, this is part of ACL's High Performance main bearing line.

