E46 4cyl to 6 cyl swap. M43 to M52tub28

[legoman67]

Recently i was asked if i could swap out the M43 in a Euro 318 for a 328 motor. The guy is attached to the car and selling it to buy a 328 or 330 was not an option. Since i cannot find any other documentation of such a swap i figured it start one.

One of the first issues that stops most people with a swap like this is the EWS. I had already previously had significant experiance working with MS43. MS42 was very similar and it did not take me long to viginize the DME. Then the fun and games began!

First i received the new engine. Old tow trucks make great engine cranes BTW



Tore it down and refreshed all the usual seals and gaskets. I wont be documenting that part here as its been well documented in the past



After that was done the owner dropped off the 318, Id never seen an M43 E46 before... they were never sold here originally.



Didnt waste any time ripping it out. Nothing new, actually went really quick, had it out within a few hours.









At this point i realized just how many other things are different between the 318 and 328. I will be posting the list at the bottom of this post for easy future reference. Meantime while i waited for parts i had to get the car out of my shop...having random tow trucks laying around came in handy again.



Between Work/school/and waiting on parts the car then sat for some time. Yesterday i finally Installed the new engine





With the 328 DME box installed everything plugged right in.



Got most of the wiring sorted today, found a few other little things that are different



Thats where we are at currently. Ill update as i make progress!

So far the parts that ive had to get to make this work.

Parts Different between 318 and 328 E46:

• Exhaust
• Driveshaft
• Differential
• CV axles
• Shifter assembly
• Entire fuel delivery system+lines from in front of rear wheel forward
• Front sway bar
• Airbox + intake
• All engine electronics(obviously)
• Secondary Air pump, and bracket
• Power steering hoses(basically all of them)
• All vacuum hoses, including right to the booster
• (to be continued....)

[Winks]

Should be an interesting car when done. I have never seen an m43 in the flesh. I have an M42 in my e30 and love it.

Good luck with the swap

[Bodderrz]

Hey mate, just taken my m43 out of my z3 but have not found any x20 connectors to the engine harness at all which has confused the fuck out of me... Got any pointers?

[legoman67]

Hey mate, just taken my m43 out of my z3 but have not found any x20 connectors to the engine harness at all which has confused the fuck out of me... Got any pointers?

The engine and body connect through various plugs in the DME box. There is no main connector like in the older cars.

FWIW this swap was completed ages ago. I forgot i started this thread.

[Bodderrz]

Ah damnnnnn, can you remember how you did it at all? Know I dug this thread up a bit haha

[legoman67]

Ah damnnnnn, can you remember how you did it at all? Know I dug this thread up a bit haha

i dont recall it clearly enough to finish this post unfortunately. but if you have specific questions i may be able to answer.