Early 325i engine on later management

[Jhonno]

Is it possible to run the earlier 2.5i (high compression) with the later engine management n loom?

[randomdave325]

yes. you have to change the waterpump, front timing cover(for the crank sensor) plug leads and front pulleys,not sure about the inlet manifold. it should be the same. other that should be no problem.

[cabrio327i]

HI there Reardiffraver, just reading that you need to change the waterpump so that you can use the later 173 motronic, why is that then? i am doing the same swop so i can use a later sport gearbox, i know the two pumps are different, the later one not having the takeoff for early header tank on the offside wing, but i would not have thought this would be a problem. cheers dave

[randomdave325]

HI there Reardiffraver, just reading that you need to change the waterpump so that you can use the later 173 motronic, why is that then? i am doing the same swop so i can use a later sport gearbox, i know the two pumps are different, the later one not having the takeoff for early header tank on the offside wing, but i would not have thought this would be a problem. cheers dave

.
i was just speaking from what i had to do when i put an earlier engine in a facelift car. Jhonno did not state which way round he was doing it. i just assumed he was putting an early engine in a facelift car. if you are putting it in an earlier car you would not have to change the waterpump. but as you are going all the effort to switch to the later motronic. why not upgrade the cooling system too. it's obviously better or bm wouldn't have changed it. you only need a radiator, header tank, pipe work and a pump. all easily and cheaply avaliable from a scappy. sorry i should of made it clearer. hope this helps

[cabrio327i]

No problem mate, see what you mean, all clear now cheers dave