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ACL Bearings Race Series Main Undersize Engine Bearing Kit

Manufacturer

Picture for manufacturer ACL Bearings

Part Number

16 part numbers · from $78.58
6 reviews
Sale Price

from $78.58

In Stock (10+)

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Usually delivered within 2 days

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Product Details

ACL Bearings Race Series main undersize engine bearings are high-performance crankshaft main bearings built for racing and high-output engine builds. They are sold in undersize options for use with reground or machined crankshafts, so builders can set the oil clearance their application needs.

Key Features:

  • Tri-metal construction: A copper-lead alloy lining on a steel back, designed to handle higher RPM and heavier bearing loads.
  • High-strength overlay: A reduced-thickness overlay plate improves fatigue properties in demanding use.
  • Undersize options: Offered in a range of crankshaft undersizes for rebuilds with reground journals.
  • Race Series engineering: Part of ACL's Race Series line for motorsport and performance engine builds.
  • Precision manufacturing: ACL is an Australian engine bearing specialist with a long history in performance and motorsport applications.

Measure the crankshaft journals and housing bores before assembly, and select the undersize that matches your journal and clearance targets. Choose the specific part number for your engine from the options on this page.

Select yours to see vehicle-specific options.

Select & Customize

16 items

Picture of ACL Bearings 5M8353H-.25 Race Series Main Bearings 0.25mm Undersize Picture of ACL Bearings 5M8353H-.25 Race Series Main Bearings 0.25mm Undersize
ACL Bearings 5M8353H-.25 Race Series Main Bearings 0.25mm Undersize
.25
Description
Specifications
Max Overall Length0.6941" (17.63mm)
Max Std Shaft Size1.9668" (49.956mm)
Max Std Tunnel Size2.1267" (54.018mm)
Max Wall at Crown0.0793" (2.013mm)
Min Std Shaft Size1.9661" (49.938mm)
Min Std Tunnel Size2.1259" (53.998mm)
Oil ClearanceStandard
Size.25
$85.77 each
PART NUMBER: 5M8353H-.25
In Stock (10+)
Usually delivered within 2 days
Picture of ACL Bearings 5M1644H-.25 Race Series Main Bearings 0.25mm Undersize Picture of ACL Bearings 5M1644H-.25 Race Series Main Bearings 0.25mm Undersize
ACL Bearings 5M1644H-.25 Race Series Main Bearings 0.25mm Undersize
.25
Description
Specifications
Size.25
$84.80 each
PART NUMBER: 5M1644H-.25
In Stock (6)
Usually delivered within 2 days
Picture of ACL Bearings 5M8309H-.025 Race Series Main Bearings .025 Undersize Picture of ACL Bearings 5M8309H-.025 Race Series Main Bearings .025 Undersize Picture of ACL Bearings 5M8309H-.025 Race Series Main Bearings .025 Undersize
ACL Bearings 5M8309H-.025 Race Series Main Bearings .025 Undersize
.025
Description
Specifications
Max Overall Length0.748" (19.00mm) w/ 8297H/HX 0.595" (15.12mm) w/ 8298H/HX 0.904" (22.95mm) w/ 8309H/HX Flange
Max Std Shaft Size2.3622" (60.000mm)
Max Std Tunnel Size2.5205" (64.020mm)
Max Wall at Crown0.0789" (2.005mm)
Min Std Shaft Size2.3616" (59.984mm)
Min Std Tunnel Size2.5197" (64.000mm)
Oil ClearanceStandard
Size.025
$104.87 each
PART NUMBER: 5M8309H-.025
In Stock (5)
Usually delivered within 2 days
Picture of ACL Bearings 5M1695H-.25 Race Series Main Bearings 0.25mm Undersize Picture of ACL Bearings 5M1695H-.25 Race Series Main Bearings 0.25mm Undersize
ACL Bearings 5M1695H-.25 Race Series Main Bearings 0.25mm Undersize
.25
Description
Specifications
Max Overall Length0.784" (19.90mm)
Max Std Shaft Size1.8898" (48.000mm)
Max Std Tunnel Size2.0492" (52.050mm)
Max Wall at Crown0.0788" (2.001mm)
Min Std Shaft Size1.8892" (47.985mm)
Min Std Tunnel Size2.0480" (52.020mm)
Oil ClearanceStandard
Size.25
$79.19 each
PART NUMBER: 5M1695H-.25
In Stock (5)
Usually delivered within 2 days
Picture of ACL Bearings 5M1144H-.25 Race Series Main Bearings 0.25mm Undersize Picture of ACL Bearings 5M1144H-.25 Race Series Main Bearings 0.25mm Undersize
ACL Bearings 5M1144H-.25 Race Series Main Bearings 0.25mm Undersize
.25
Description
Specifications
Max Overall Length0.906" (23.00mm) w/ 1147H/HX & 1144H/HX 1.140" (28.95mm) w/ 1148H/HX Flange
Max Std Shaft Size2.2441" (57.000mm)
Max Std Tunnel Size2.4024" (61.021mm)
Max Wall at Crown0.0783" (1.990mm)
Min Std Shaft Size2.2433" (56.980mm)
Min Std Tunnel Size2.4016" (61.000mm)
Oil ClearanceStandard
Size.25
$113.33 each
PART NUMBER: 5M1144H-.25
4 left at this price
Usually delivered within 2 days
Picture of ACL Bearings 5M1913H-.25 Race Series Main Bearings Picture of ACL Bearings 5M1913H-.25 Race Series Main Bearings Picture of ACL Bearings 5M1913H-.25 Race Series Main Bearings Picture of ACL Bearings 5M1913H-.25 Race Series Main Bearings
ACL Bearings 5M1913H-.25 Race Series Main Bearings
.25
Description
Specifications
Max Overall Length0.787" (20.00mm)
Max Std Shaft Size2.1654" (55.000mm)
Max Std Tunnel Size2.3630" (60.020mm)
Max Wall at Crown0.0986" (2.504mm)
Min Std Shaft Size2.1644" (54.976mm)
Min Std Tunnel Size2.3622" (60.000mm)
Oil ClearanceStandard
Size.25
$88.72 each
PART NUMBER: 5M1913H-.25
4 left at this price
Usually delivered within 2 days
Picture of ACL Bearings 5M1913H-.025 Race Series Main Bearings Picture of ACL Bearings 5M1913H-.025 Race Series Main Bearings
ACL Bearings 5M1913H-.025 Race Series Main Bearings
.025
Description
Specifications
Max Overall Length0.787" (20.00mm)
Max Std Shaft Size2.1654" (55.000mm)
Max Std Tunnel Size2.3630" (60.020mm)
Max Wall at Crown0.0986" (2.504mm)
Min Std Shaft Size2.1644" (54.976mm)
Min Std Tunnel Size2.3622" (60.000mm)
Oil ClearanceStandard
Size.025
$88.72 each
PART NUMBER: 5M1913H-.025
3 left at this price
Usually delivered within 2 days
Picture of ACL Bearings 4M2633H-.025 Race Series Main Bearings 0.025mm Undersize Picture of ACL Bearings 4M2633H-.025 Race Series Main Bearings 0.025mm Undersize
ACL Bearings 4M2633H-.025 Race Series Main Bearings 0.025mm Undersize
.025
Description
Specifications
Max Overall Length0.792" (20.12mm) w/ 2633H/HX
Max Std Shaft Size2.3612" (59.975mm)
Max Std Tunnel Size2.5203" (64.017mm)
Max Wall at Crown0.0843" (2.140mm)
Min Std Shaft Size2.3603" (59.951mm)
Min Std Tunnel Size2.5194" (63.993mm)
Oil ClearanceStandard
Size.025
$91.57 each
PART NUMBER: 4M2633H-.025
3 left at this price
Usually delivered within 2 days
Picture of ACL Bearings 7M2428H-.25 Race Series Main Bearings 0.25mm Undersize Picture of ACL Bearings 7M2428H-.25 Race Series Main Bearings 0.25mm Undersize
ACL Bearings 7M2428H-.25 Race Series Main Bearings 0.25mm Undersize
.25
Description
Specifications
Max Overall Length1.063" (27.00mm) w/ 2428H/HX Flange 0.787" (20.00mm) w/ 2429H/HX
Max Std Shaft Size2.1644" (54.975mm)
Max Std Tunnel Size2.3094" (58.658mm)
Max Wall at Crown0.0719" (1.827mm)
Min Std Shaft Size2.1634" (54.951mm)
Min Std Tunnel Size2.3089" (58.645mm)
Oil ClearanceStandard
Size.25
$148.99 each
PART NUMBER: 7M2428H-.25
1 left at this price
Usually delivered within 2 days
Picture of ACL Bearings 4M2737H-.025 Race Series Main Bearings 0.025mm Undersize
ACL Bearings 4M2737H-.025 Race Series Main Bearings 0.025mm Undersize
.025
Description
Specifications
Max Overall Length0.748" (19.00mm) w/ 2737H/HX 1.136" (28.85mm) w/ 2738H/HX Flange 0.886" (22.50mm) w/ 2739H/HX
Max Std Shaft Size2.4793" (62.974mm)
Max Std Tunnel Size2.6249" (66.672mm)
Max Wall at Crown0.0720" (1.830mm)
Min Std Shaft Size2.4784" (62.951mm)
Min Std Tunnel Size2.6238" (66.645mm)
Oil ClearanceStandard
Size.025
$126.60 each
PART NUMBER: 4M2737H-.025
1 left at this price
Usually delivered within 2 days
Picture of ACL Bearings 5M1695H-.50 Race Series Main Bearings -0.50mm Undersize
ACL Bearings 5M1695H-.50 Race Series Main Bearings -0.50mm Undersize
.50
Description
Specifications
Max Overall Length0.784" (19.90mm)
Max Std Shaft Size1.8898" (48.000mm)
Max Std Tunnel Size2.0492" (52.050mm)
Max Wall at Crown0.0788" (2.001mm)
Min Std Shaft Size1.8892" (47.985mm)
Min Std Tunnel Size2.0480" (52.020mm)
Oil ClearanceStandard
Size.50
$79.19 each
PART NUMBER: 5M1695H-.50
1 left at this price
Usually delivered within 2 days
Picture of ACL Bearings 5M8297H-.25 Race Series Main Bearings 0.25mm Oversize
ACL Bearings 5M8297H-.25 Race Series Main Bearings 0.25mm Oversize
.25
Description
Specifications
Max Overall Length0.748" (19.00mm) w/ 8297H/HX 0.595" (15.12mm) w/ 8298H/HX 0.864" (21.95mm) w/ 8299H/HX Flange
Max Std Shaft Size2.3622" (60.000mm)
Max Std Tunnel Size2.5205" (64.020mm)
Max Wall at Crown0.0789" (2.005mm)
Min Std Shaft Size2.3616" (59.984mm)
Min Std Tunnel Size2.5197" (64.000mm)
Oil ClearanceStandard
Size.25
$103.99 each
PART NUMBER: 5M8297H-.25
Ships from manufacturer
Picture of ACL Bearings 5M1959H-.25 Race Series Main Bearings 0.25mm Oversize Picture of ACL Bearings 5M1959H-.25 Race Series Main Bearings 0.25mm Oversize
ACL Bearings 5M1959H-.25 Race Series Main Bearings 0.25mm Oversize
.25
Description
Specifications
Max Overall Length0.7874" (20.00mm)
Max Std Shaft Size2.1654" (55.000mm)
Max Std Tunnel Size2.3236" (59.020mm)
Max Wall at Crown0.0790" (2.007mm)
Min Std Shaft Size2.1646" (54.980mm)
Min Std Tunnel Size2.3228" (59.000mm)
Oil ClearanceStandard
Size.25
$78.58 each
PART NUMBER: 5M1959H-.25
Ships from manufacturer
Picture of ACL Bearings 5M2797H-.50 Race Series Main Bearings 0.50mm Oversize
Representative Photo. Actual item may vary
ACL Bearings 5M2797H-.50 Race Series Main Bearings 0.50mm Oversize
.50
Description
Specifications
Size.50
$109.41 each
PART NUMBER: 5M2797H-.50
Ships from manufacturer
Picture of ACL Bearings 5M8337H-.25 Race Series Main Bearings 0.25mm Oversize
Representative Photo. Actual item may vary
ACL Bearings 5M8337H-.25 Race Series Main Bearings 0.25mm Oversize
.25
Description
Specifications
Size.25
$106.14 each
PART NUMBER: 5M8337H-.25
Ships from manufacturer
Picture of ACL Bearings 5M2964H-.25 Race Series Main Bearings 0.25mm Oversize Picture of ACL Bearings 5M2964H-.25 Race Series Main Bearings 0.25mm Oversize Picture of ACL Bearings 5M2964H-.25 Race Series Main Bearings 0.25mm Oversize Picture of ACL Bearings 5M2964H-.25 Race Series Main Bearings 0.25mm Oversize
ACL Bearings 5M2964H-.25 Race Series Main Bearings 0.25mm Oversize
.25
Description
Specifications
Max Overall Length0.752" (19.10mm)
Max Std Shaft Size2.1646" (54.980mm)
Max Std Tunnel Size2.3216" (58.968mm)
Max Wall at Crown0.0780" (1.980mm)
Min Std Shaft Size2.1636" (54.956mm)
Min Std Tunnel Size2.3206" (58.944mm)
Oil ClearanceStandard
Size.25
$84.77 each
PART NUMBER: 5M2964H-.25
Ships from manufacturer
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Select & Customize

Easy to order however this is my first order with them.

Found what I needed

Placing order was good. Too early to tell if everything is good.

used on line, placed order allwent well

good

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