Engines and Components› Engine Bearings

ACL

Performance Main Engine Bearings

$64.99

SKU: 5M1959H-4B1925H

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In Stock
Ships by Sep 12
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$100 Minimum Order
30 Days Return
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Overview

The ACL 5M1959H is a set of performance main engine bearings. These bearings are constructed from a trimetal alloy steel and feature an increased crush for improved retention.

They are designed to withstand higher RPM conditions and include 3/4 grooved main bearings to optimize load carrying surface area and oil flow. The bearings also feature enlarged ID chamfers where required for performance crankshafts.
Show original supplier description
The ACL Race Series Main Bearings (5M1959H) are engineered for high-performance applications, offering superior durability and reliability. Constructed from a high-strength trimetal alloy with a reduced thickness overlay plate, these bearings provide improved fatigue properties. They feature hardened steel backs for enhanced support and retention, and an increased crush design for a more secure fit within the housing. The elimination of flash plating on the back improves heat transfer, maximizing the grip between the bearing and its housing. The 3/4 grooved main bearings are optimized to enhance load-carrying capacity and oil flow to the connecting rod bearings, ensuring consistent lubrication. Tight wall tolerances are maintained to help achieve precise clearances. Key features include enlarged ID chamfers on bearing edges to accommodate large fillet radii on performance crankshafts. These bearings are specifically designed for Honda/Acura B18C1 and B18C5 engines, including the 1994-2001 Acura Integra GS-R and the 2000-2001 Acura Integra Type-R.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandACL
Part Number5M1959H-4B1925H
CategoryEngines and Components

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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