What is the purpose of main bearings in an engine?

Main bearings are a critical component that supports the crankshaft within the engine block. They allow the crankshaft to rotate smoothly while handling the immense forces generated during combustion, ensuring proper engine operation.

Why do these bearings have extra oil clearance?

The extra .001 inch of oil clearance helps to manage increased heat and potential expansion in high-performance or heavily used engines. This allows for better oil flow around the crankshaft, which can help reduce friction and wear.

Are these bearings suitable for a stock engine rebuild?

Yes, these standard size bearings with the added clearance are a solid option for both stock engine rebuilds and performance applications. They offer improved oil management that can benefit any engine, especially those that see demanding use.

ACL BMW N63B44/S63B44 4.4L V8 Standard Size Main Bearings

Specifications

Brand: ACL
Part #: 5M1573HX-STD
UPC: 9315726470237

ACL BMW N63B44/S63B44 4.4L V8 Standard Size Main Bearings

Name: ACL BMW N63B44/S63B44 4.4L V8 Standard Size Main Bearings
Brand: ACL
Price: 266.87 USD
Availability: InStock

$266.87

On Backorder

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Fits 2012-2018 BMW M6. ACL standard size main bearings for the N63B44/S63B44 4.4L V8, offering an extra .001" oil clearance.

Key Features

Fits 2012-2018 BMW M6.
Also fits 2009-2012 BMW 750i, 2013-2016 BMW M5, and 2011-2013/2015-2018 BMW X5.
Standard size main bearing set for BMW N63B44 and S63B44 4.4L V8 engines.
Features an extra .001 inch of oil clearance for improved oil flow and heat management.
Well-built to support the crankshaft in high-performance applications.

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Will this fit your vehicle?

Product Details

Already running a high-performance setup on your BMW? This main bearing set is the next piece of the puzzle for your N63B44 or S63B44 4.4L V8 engine. These bearings are crucial for supporting the crankshaft and ensuring smooth rotation within the engine block. When you're pushing your engine harder, whether it's for track days or spirited driving, having reliable bearings that can handle the extra stress is essential.

ACL has engineered these main bearings to be a standard size but with an added .001 inch of oil clearance. This slight increase in clearance helps to manage the increased heat and potential expansion that can occur under demanding conditions, promoting better oil flow and reducing friction. They are well-built to handle the rigors of a performance V8, offering a solid option for rebuilding or upgrading your engine's bottom end.

This set is designed to fit a range of BMW models including the 750i, M5, M6, and X5, all equipped with the 4.4L V8 engine. When you're working on your engine, using bearings that fit right and are made to last is key to a successful build.