An M54B30 would be pretty much plug and play electrically. You'll probably need to get a new MAF since 330s come w/ larger intakes. And depending on the year of your car/the donor car, you may need to change a few sensors due to the ECU change that occured in 03/2003. Install the USB cable and route it inside the vehicle. Connect the vehicle harness ECU connectors to the MaxxECU adapter harness connectors. 10. Wire in some extra sensors/outputs in the 8-pin extra connector, and also for boosted application you can use the extra 2-pin superseal connector to a boost solenoid. Only relatively recently has the M54 become a noteworthy and beloved swap in the E30 community for a few reasons. Most of the vehicles that came from the factory with an M54, 330i E46s, and 530i E39s being the most common, have hit the bottom of their depreciation curve while also existing in large quantities.