87 320i to 1990 engine conversion

[b-buzzin 0]

Engine in my 87 320i recently spat the dummy and now eyeing up a 1990 to replace it with just wondering if its a straight swap. any help appreciated

[QuickSilver 0]

It is almost a straight swap, the pre-facelift and face-lifts use different engine management systems, your 87 uses jetronic, and the 90 uses motronic.

You need to make sure that when you pick up the new motor you need to pick up the complete loom with it.

Its as simple as removing the old motor complete with the old loom, and installing the new motor with its own loom attached, push the new plug through the firewall, plug in the ecu and your away.

There is one small thing you need to modify with the rev counter but its not a big job.

Old motor out,

New motor in,

Drive.

[hotwire 352]

It is almost a straight swap, the pre-facelift and face-lifts use different engine management systems, your 87 uses jetronic, and the 90 uses motronic.

You need to make sure that when you pick up the new motor you need to pick up the complete loom with it.

Its as simple as removing the old motor complete with the old loom, and installing the new motor with its own loom attached, push the new plug through the firewall, plug in the ecu and your away.

There is one small thing you need to modify with the rev counter but its not a big job.

Old motor out,

New motor in,

Drive.

A little more than that, the vehicle - engine loom is also a different plug set up so one or other needs splicing in.

Also - make sure you also get the Motronic ECU.

[gmccormack 0]

Also, the engines exhaust manifold (4 stud) will not match the cars exhaust system (3 stud) and there will be no oxygen sensor fitting in the cars exhaust either. Be sure to get the radiator and hoses that belong to the 90 engine, they are different too.

[hotwire 352]

Also, the engines exhaust manifold (4 stud) will not match the cars exhaust system (3 stud) and there will be no oxygen sensor fitting in the cars exhaust either. Be sure to get the radiator and hoses that belong to the 90 engine, they are different too.

Yep - Dead right - forgot about all that too.

Another option is to convert the Motronic engine managment to suit Ljet

Need to fit distributor in place of blank

Change water pump, front covers (remove motronic distributor)

Swap engine looms

[QuickSilver 0]

A little more than that, the vehicle - engine loom is also a different plug set up so one or other needs splicing in.

Also - make sure you also get the Motronic ECU.

I've just finished swapping my 87 320i to a facelift (motronic 1.3) 327i, the c101 plugs are both the same, they both use the round plug sitting on the firewall, there is no other wiring that needs changing except to connect the rev counter as it isnt directly connected to the L-JET MCU plug. The c101 plugs are all set up the same and will plug and play unless someone has played with them.

Unless your 87 e30 uses the square plug on the firewall, then its different, but my 87 e30 didnt?

As far as I know facelift 320i's were equipped with motronic 1.3? Which means its the same setup as what I've just swapped.

I did forget about the exhaust downpipe ( I welded the 4 stud downpipe onto my exhaust ) and the radiator (which also needs the mounts from the 90 car), but if one picks up the entire set there is no problem, if you just use what you get from the 90 motor nothing needs changing. My motronic motor does not use an oxygen sensor.

EDIT: There are other things to do also, but they are minor, IE coil is mounted on the right as opposed to the left, the expansion task in on the left as opposed to right, and if you have cruise control in your 87 e30 mounted in the bottom left you will need to move it and attach it to the expansion tank (it has mounting holes)

Edited August 18, 2008 by QuickSilver

[b-buzzin 0]

ohk im pritty sure i understand what you guys have told me . I had plans of getting the whole car and pulling it out my self but i have since missed out on it but thats not too say i wont be putting the suggestions to work just a matter of finding another donor car. much appreciated guys!