Engines and Components› Engine Bearings

ACL

Performance Engine Main Bearings

$207.99

SKU: CAL-5M1644H-1

In Stock
In Stock
Ships by Sep 12
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The ACL 5M1644H-1 is a set of performance engine main bearings featuring a Trimetal construction with Calico CT-1 coating. The set includes a complete set for all main caps, with specific configurations of oil grooves for optimal lubrication.
Show original supplier description
The ACL Race Series 5M1644H-1 main bearing set offers a premium solution for high-performance engine builds, combining ACL's robust Trimetal lining with Calico's renowned CT-1 coating. This coating acts as a dry film lubricant, reducing friction and wear while providing intermittent dry lubrication. The base bearing shells are constructed with a hardened steel backing and increased bearing crush for superior retention, and feature increased ovality to better handle rod distortion at high RPMs. This complete set is designed for all main caps and includes six bearings with oil grooves and four without, with specific placement for the #4 journal.

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 NumberCAL-5M1644H-1
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.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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