ACL 4B1185H-STD Mitsubishi 4G63/4G64 Rod Bearings

4B1185H-STD Race Series Rod Bearings for Mitsubishi 4G63 and 4G64

ACL 4B1185H-STD is a standard-size H-series connecting rod bearing set for cataloged 1997-on Mitsubishi 4G63, turbocharged 4G63T, and 4G64 engine configurations that use the separate-thrust-washer bearing arrangement. Confirm the exact engine generation, block, crankshaft, journal dimensions, housing bore, thrust design, and assembled clearances before ordering.

Key Features

• ACL performance-engine bearing construction for measured street and competition builds
• Cataloged for later Mitsubishi 4G63, 4G63T, and 4G64 configurations
• Standard-size H-series configuration
• Application-specific geometry, locating features, and bearing position
• ACL 4B1185H-STD must be selected by exact engine and measured dimensions

Fitment

Vehicle year and model alone do not confirm compatibility. Earlier flange-main engines, engine swaps, mixed blocks and crankshafts, and previously machined assemblies can require different components.

ACLs 2023 guide also catalogs this rod-bearing family for the 19921997 4G63, 4G63T and 4G64 flange-main engine arrangement. Main-bearing selection remains different: 5M1186 for the flange-main arrangement and 5M1219 for the 1997-on separate-thrust-washer arrangement. Confirm the actual assembly at the changeover; shared rod bearings do not make the main sets interchangeable.

Specifications

Whats Included

• One ACL Race Series connecting rod bearing set
• Manufacturer packaging and identification for ACL 4B1185H-STD
• Only the component identified in this listing is included unless the package contents state otherwise

About ACL

ACL manufactures precision engine bearings for performance street, racing, and professional engine-building applications. Correct machining, clean assembly, proper fastener loading, and measured clearances are essential to bearing life.

Related Parts

Use the same verified 1997-on engine family when pairing these components:

• ACL 5M1219H-STD main bearings
• ACL 1T1219-STD thrust washers
• ACL 5M1219HX-STD HX main bearings

Frequently Asked Questions

What is the 4B1185H-STD?

It is an ACL connecting rod bearing set for the cataloged later Mitsubishi 4G63, 4G63T, and 4G64 bearing family.

Does this fit every 4G63 or 4G64?

No. Confirm the exact engine generation and bearing arrangement before ordering.

Can vehicle year and model confirm fitment?

No. Verify the block, crankshaft, engine code, journal dimensions, and thrust design.

Must clearances be measured?

Yes. A qualified engine builder should measure every relevant journal, housing bore, and assembled clearance.

Can I substitute another size suffix?

No. Standard, repair-size, and extra-clearance suffixes identify different dimensional requirements.

Are all related bearings included?

No. Main bearings, rod bearings, and thrust washers are separate components unless the listing explicitly states otherwise.

Will this work with a mixed block and crankshaft?

Do not assume compatibility. Mixed engine components require direct dimensional verification.

Should a professional install these parts?

Yes. Precision engine-bearing installation should be completed or checked by an experienced engine builder.

Installation Instructions

1. Confirm ACL 4B1185H-STD against the engine build sheet and measured requirements.
2. Verify the block, crankshaft, bearing locations, and thrust arrangement.
3. Measure journals and housing bores with calibrated tools.
4. Clean all mating surfaces, oil passages, and bearing components.
5. Check locating features, oil-hole alignment, fillet clearance, and component orientation.
6. Install and torque fasteners using the engine builders specified sequence and procedure.
7. Measure assembled clearances, endplay where applicable, and free rotation.
8. Apply approved assembly lubricant and prime the oiling system before startup.