don't hold me to it but Everything i would imagine is the same Minus the Ecu. They are pretty much identical motors Except the 318i motor is a 8valve motor & the 318is is a 16valve motor

If anything the most i would imagine the swap to take would be Motor,Wiring harness, & Ecu. I would imagine the trannys are the same. Hope this helps out I just don't know much about the 4 bangers & swaps.
Try a more bmw related site