E30 320i Needs new motor...can the 325i fit with no hassle??

[89E30320i]

Hi there,

I need a new motor for my 1989 BMW 320i.

I have found two motors that I can buy.

One is a standard E30 320i 2.0 litre motor and the other is from a E30 325i (2.5 lite motor).
I was wondering if the 2.5 litre motor can be fitted to my 320i without any dramas or modifications.
I would consider buying the 2.5 litre motor, only if it will not lead to a major increase in the labour cost to fit the motor.

Does the 2.5litre motor mate up with the gearbox, driveshaft, etc of the 320i?

I would love the extra power of the 2.5 motor, but only if it is a straight fit and will not cost more to fit than the 2.0 motor.

Also, anyone know if fiting the M50 motor from a E36 325i is relatively simple and cheap as well? would consider this too if reasonable.

Any help or advise would be appreciated.

Cheers

[jaistanley]

Just swap the engine, engine loom and ECU from the 325i. No mucking about.

As for fitting an M50 motor: It's an excellent idea and very easy, but not the direct swap you might be hoping for. See the M50 developments threads and many recent M50 engine swap threads.

HTH

Jai

[Brianmoooore]

320 engine wiring loom is identical to a 325 one, and the 320 ECU can be used if fitted with a 'chip' for a 325, if your engine comes without these.
You will need to use a 325 air meter (AFM), and a 320 diff in a 325 would drive me nuts.

[secondtimelucky]

Why pay someone to do it??? i mean honestly.... I managed to swap these engines over and all i done before was servicing it really is that easy bud.

GET THE SPANNERS OUT!!! And an engine crane

[stonesie]

Whatever engine you fit, treat it to a new sump gasket BEFORE you fit it

[secondtimelucky]

Whatever engine you fit, treat it to a new sump gasket BEFORE you fit it

Wise words right there, its a pig to do 'in-car'

[89E30320i]

Thanks for all the info guys. Really helped a lot. I'm gonna go with the 2.5 litre E30 325i motor. Will consider an M50 upgrade later when cash is more available. M50 swap would obviously require a new gearbox, driveshaft, diff etc?

So the 325i motor will work fine with the 320i gearbox and diff?

[Brianmoooore]

M50 swap would obviously require a new gearbox, driveshaft, diff etc?

Not necessarily - these can all be used, if not ideal.
The M50 engine drops into an E30 with no problems at all. The problems arise because the M50's inlet and exhaust system occupy bits of the engine bay that are already occupied by bits of E30.

[89E30320i]

So, I gather everyone here who has given me this advice is speaking from experience or knows this to be the case 100% positively?

[Brianmoooore]

M20B25 engine, complete with ECU and all inlet side stuff can be used as a direct replacement for a M20B20.
If your 325 comes without the oil cooler, just fit the oil filter assembley from the 320.