ACL Race Series Main Bearing Set for BMW N63B44 and S63B44 4.4L V8, 0.025 mm Oversize, Part Number 5M1573H-.025

Race Series Main Bearing Set - 0.001 undersize for BMW N63B44, S63B44 4395cc V8 DOHC 4v

Upgrade the bottom-end reliability of your BMW performance engine with the ACL Race Series Main Bearing Set, Part Number 5M1573H-.025. Designed for BMW N63B44 and S63B44 4.4L V8 DOHC engines, this main bearing set is engineered for demanding street, track, and high-performance applications. The 0.025 mm oversize specification is intended for crankshafts machined to the corresponding undersize journal dimension, making accurate crankshaft measurement and proper bearing clearance verification essential before installation.

ACL Race Series bearings are manufactured with performance-focused materials and design features to support dependable load handling, oil control, and durability under elevated engine speeds and operating temperatures. The bearing construction helps provide a stable surface for the crankshaft journals while supporting consistent lubrication across the main bearing assemblies. This set is suited to professional engine rebuilding and performance-focused BMW applications where precise fitment and reliable bottom-end operation are priorities.

This automotive replacement component fits select BMW M5 and M6 models equipped with compatible N63B44 or S63B44 engines, including model years from 2012 through 2017. Confirm engine code, crankshaft journal condition, required bearing grade, and final oil clearance specifications before ordering. Professional installation is recommended, including inspection of the block and crankshaft, verification of bearing orientation, and measurement of installed clearance according to the engine builder’s procedures.

Product Specifications and Technical Data

• Brand: ACL
• Series: Race Series
• Part Number: 5M1573H-.025
• Application: Main bearing set
• Engine Compatibility: BMW N63B44 and S63B44
• Engine Configuration: 4.4L V8 DOHC 32-valve
• Bearing Size: 0.025 mm oversize
• Vehicle Type: Automotive performance and replacement application

What's Included

One ACL Race Series main bearing set for the specified BMW engine application. Crankshaft machining, installation hardware, and additional engine components are not included.

Features:

• BMW V8 Compatibility: Designed for select N63B44 and S63B44 4.4L V8 DOHC engines used in BMW M5 and M6 applications.
• Race Series Construction: Engineered to support dependable main bearing performance in demanding street, track, and high-output engine environments.
• 0.025 mm Oversize Specification: Intended for crankshafts machined to the matching undersize journal dimension; verify measurements before installation.
• Consistent Lubrication Support: Precision bearing design promotes stable crankshaft support and reliable oil distribution when installed with correct clearances.

Fitments:
2009 BMW 750i Base
2010 BMW 750i Base
2011 BMW 750i Base
2011 BMW X5 xDrive50i
2012 BMW 750i Base
2012 BMW M6 Base
2012 BMW X5 xDrive50i
2013 BMW M5 Base
2013 BMW M6 Base
2013 BMW X5 xDrive50i
2014 BMW M5 Base
2014 BMW M6 Base
2015 BMW M5 Base
2015 BMW M6 Base
2015 BMW X5 M
2015 BMW X5 xDrive50i
2016 BMW M5 Base
2016 BMW M6 Base
2016 BMW X5 M
2016 BMW X5 xDrive50i
2017 BMW M6 Base
2017 BMW X5 M
2017 BMW X5 xDrive50i
2018 BMW M6 Base
2018 BMW X5 M
2018 BMW X5 xDrive50i

Air Freight Prohibited: false
Not Carb Approved: false
Ltl Freight Required: false
Prop 65: Unknown
Part Type: automotive
Epa: N/A
Carb Acknowledgement Required: false
Regular Stock: t
Units Per Sku: 1