Hi, i have recently bought a 1987 325 donor car from which I would like to use the engine to convert my 320i SE 1990, would this be just a straight swap and ecu change or would I need to change the engine harness and the ecu?
Thanks
1987 325 to 1990 320i SE conversion?
Moderator: martauto
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jimbom30cab
- Tech 1 freak
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Drop the new engine in with the wiring loom still fitted, easier that way. (its the same loom by the way)
You might need to change the diff to a lower number ratio.
Plug and play buddy !
enjoy
You might need to change the diff to a lower number ratio.
Plug and play buddy !
enjoy
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Brianmoooore
- E30 Zone Team Member
- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
'87 was a change over year for the engine management system, so I wouldn't be certain that the loom is the same. Post up the ECU number for the 325, so that we can tell.
If the looms are different, it would be best to use the 320 loom and convert the 320 ECU to 325 spec. by changing the 'chip'.
There may be an issue if your 320 has ABS. Check what is connected to pin 20 on each side of the C101 engine loom plug and socket. If the car side has a red/yellow wire (and you have ABS), then you will need an loom with a corresponding red/yellow, which the 320 loom will obviously have, but if you use the 325 loom, and it doesn't have the wire, it will need to be added.
You should also check out the condition of the wires under the rubber covers of the plug and socket under the inlet manifold, as water can collect inside these covers and rot the wires.
Whichever loom you use, it should be fitted to the engine before the engine is fitted to the car, as already said above.
If the looms are different, it would be best to use the 320 loom and convert the 320 ECU to 325 spec. by changing the 'chip'.
There may be an issue if your 320 has ABS. Check what is connected to pin 20 on each side of the C101 engine loom plug and socket. If the car side has a red/yellow wire (and you have ABS), then you will need an loom with a corresponding red/yellow, which the 320 loom will obviously have, but if you use the 325 loom, and it doesn't have the wire, it will need to be added.
You should also check out the condition of the wires under the rubber covers of the plug and socket under the inlet manifold, as water can collect inside these covers and rot the wires.
Whichever loom you use, it should be fitted to the engine before the engine is fitted to the car, as already said above.