Hack Engineering S54 Big End Upgrade Kit (E46 M3/Z3M/Z4M)
From £0.00
Reserve for delivery. This item is not on the shelf at Hack Engineering, but your order will be processed and delivered as quickly as possible.
Lead Time: Generally 1-2 weeks when not in stock
Big end bearing upgrade package for the S54B32 engine, as found in the E46 M3, late Z3 M and Z4 M – vital maintenance for engine longevity.
- Description
Description
Selecting Your Bearings
We are asked time and time again about which bearing sizes are the right ones to purchase – if you are in any doubt, then choose the ‘Standard Sizing’ option for a bearing that ACL have formulated to be a replacement for the originals. ACL’s bearing clearances tend to measure at the larger side of OE tolerance, making them ideal for high performance applications.
‘0.025mm’ options have an oil clearance which is 0.025mm tighter than ACL’s standard option; this is for crankshafts that measure as being undersized by a very small amount; usually due to wear. ‘HX Extra Clearance’ bearings are the other way around, with 0.025mm more clearance than the standard size. These are generally only for extreme duty drag race applications and must be specified by an engine builder.
‘0.25mm’ and ‘0.50mm’. bearings, where available, are specifically for reground crankshafts. These options should be ignored unless your crankshaft has been machined to the correct specifications by your machine shop.
In all cases it is advised that oil clearances are measured by an engine builder or qualified professional for the best results; bearing clearances are a critical element to engine longevity and performance and must not be overlooked.










