Hi all
Am relatively new to engine rebuilds so bear with me. I have had a good look around this forum, some great advice.
Simple question - i have a '90 320, and have a chance to get an engine from a '91 325. Should have the same injection system and loom , so all I woudl need really is the ECU ??
Cheers
325 engine into 320
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Pretty sure that's correct as the 320 engine management loom etc can
all be used in swapping to the later Motronic system for an early 325i.
Apart from the 320 ECU, which can be chipped if you wanted to use it w.ith the 325i
all be used in swapping to the later Motronic system for an early 325i.
Apart from the 320 ECU, which can be chipped if you wanted to use it w.ith the 325i

straight drop in swap..
the 320i ECU will run the 2.5 but some of the maps are slightly different. you could either change the 320i ECU for a 325i ECU or simply change the chip over to a 325i chip.
a 90 320i should have either a 172 or 381 ECU, similar era 325i should have a 173 or 380. the ECU's themselves are itentical apart from the chip inside. also the 17X ECU's are a little more robust than the 38X as the 38X has dual boards inside and have been known to be a little more problematic.
the 320i ECU will run the 2.5 but some of the maps are slightly different. you could either change the 320i ECU for a 325i ECU or simply change the chip over to a 325i chip.
a 90 320i should have either a 172 or 381 ECU, similar era 325i should have a 173 or 380. the ECU's themselves are itentical apart from the chip inside. also the 17X ECU's are a little more robust than the 38X as the 38X has dual boards inside and have been known to be a little more problematic.
WMMotorsports




