US RWD E46 325i/325Ci and 330i/330Ci M54 Engine and Long-Block Donor Identification

The checked BMW catalogs separate M54B25 and standard M54B30 branches and divide each at 09/2002 production. Each new-versus-exchange pair is recorded as a catalog package relationship, not proof that a complete donor's accessories, electronics, oil-pan package or transmission preparation interchange. No M54B25-to-M54B30, standard-330-to-ZHP, RWD-to-xi, M54-to-M56 or pre/post-09/2002 blanket supersession is asserted.

Begin with recipient and donor VINs/build dates, body, emissions label, exact engine family/code and photographs of the block/head labels and physical assembly. Match the 09/2002 service branch and confirm standard-output versus S767A/ZHP. A BMW short-engine catalog entry is transmission-neutral evidence only for that cataloged assembly level; it does not prove that a complete automatic donor's flexplate, a manual donor's flywheel, harness, DME/EWS, intake, exhaust, fuel, cooling, accessories, mounts or oil-pan package fit another car. Require a written inventory of block, head, covers, oil pan/pickup, intake, exhaust, fuel rail/injectors, coils, cooling parts, sensors, harness, accessories, mounts and flywheel/flexplate. For used or remanufactured units require donor VIN/mileage, cold-start or run evidence where lawful, qualified compression and leak-down results with method, oil-pressure or internal-inspection evidence where warranted, contamination checks, overheating/oil-starvation history, modifications, warranty, core and freight terms. Reject cracked castings or mounts, stripped threads, poor or uneven compression/leak-down, oil/coolant mixing, metal contamination, water/fire/flood exposure, open ports, cut wiring or undisclosed internal work. Require lawful fluid removal, protected stable freight and qualified installation, current BMW service, coding and emissions review; no swap, immobilizer-bypass or emissions-defeat instructions are provided.

A VIN/build- and engine-code-matched remanufactured M54B25 or standard M54B30 long block may be compared only after the rebuilder itemizes its internal specification, assembly level, oil-pan/pickup, covers, accessories, transmission preparation, warranty, labor coverage and core terms. Performance, mixed-displacement, ZHP-labeled, M56, xi, non-US and swap packages are outside this donor-identification claim.

This is not universal E46 or M54 interchange. Match both VINs/builds, RWD body, M54B25 versus standard M54B30, the 09/2002 service branch and standard-330 versus ZHP status. Short engine, long block and complete takeout are not synonyms; itemize the oil-pan package, transmission preparation, electronics, accessories and every included part. Require documented internal condition and reject overheating, poor compression/leak-down, broken castings or mounts, contamination, open ports and incomplete inventory.

Supersede reviewed 12 unique research sources for this guide. 5 also appear above as a seller or official action and are not repeated here; 7 additional citations follow.

Research last verified 2026-08-06.

1. RealOEM — showpartsOpen source
2. RealOEM — showpartsOpen source
3. Bmwpartsdeal — short engineOpen source
4. Bmwpartsdeal — short engineOpen source
5. Bmwrepairguide — ST055 Engine ElectronicsOpen source
6. Ia801005 us archive — 08 SULEVOpen source
7. NHTSA — SB 10016620 2147Open source