The E46 has a mixed reputation. On the one hand they recaptured the spirit of the E30, finding the correct balance between sporty handling and refined cruising. On the other, it took very little time for signs of BMW's cost-cutting to show through, with rusting front wings and a reputation for cracked rear subframe mounts topping the long list of known issues. Surprisingly the older models with M53 or M43 engines are more desirable than the later models, especially those with the N42 engine which has proved to be fragile and unreliable. These days only the bigger six-cylinder models are worth their price.
These are the parts can be bolted directly to the E30 with little or no modification. They are considered an upgrade for either strength, performance or cost reasons. Anything not on this list is either directly incompatible or requires significant fabrication to fit.
Main article: Engine Swaps
- M50/M52 2.0, 2.5 and 2.8
NOTE: The E46 featured both M52 and M54 engines. While these two lumps belong to the same family, the earlier M52 is considered better for engine swaps due to its more robust design and simpler electronics. The M54 can be used but the ECU requires 'flashing' in order to compensate for the lack of electronics in a standard E30.
The E46 steering rack is one of the best replacements for the E30 unit, surpassing both the Z3 and E36 units in popularity and availability. They are used in conjunction with E30 track rods and track rod ends.
Two types of rack are available. The standard E46 rack with 3.4 turns, or the Clubsport '067' rack with 3.0 turns.
Despite the complex rear multi-link setup, the E46 uses a similar top mount design to the E30. These reinforced units are a significant improvement when replacing E30 suspension bushes.