powertrain swap - United Bimmer Community

**guilty1** · 03-16-2008, 07:05 PM

I have 2 BMW
1) 1985 318i 2 door 5 spd
2)1986 325e 4 door 5 spd
Can the owertrain AND the driveshaft be taken out f the 4 door and put into the 2 door?
Will the driveshaft be too long or would I have to reuse the driveshaft from the 2 door?

johnnybayonne · 03-16-2008, 07:51 PM

Quote:

Originally Posted by guilty1

I have 2 BMW
1) 1985 318i 2 door 5 spd
2)1986 325e 4 door 5 spd
Can the owertrain AND the driveshaft be taken out f the 4 door and put into the 2 door?
Will the driveshaft be too long or would I have to reuse the driveshaft from the 2 door?

CALL DINAN & ask them!!! 800-341-5480. Tell them you are UB member you would like to know if it is possible!

**Antiburn** · 03-16-2008, 07:52 PM

You will need to change the front subframe, drive shaft, instrument cluster, and possibly redrill rear trans mounts but it might fit. You would want to use the same diff. Auto's tend to have a better gear ratio then manuals which you can find out at realoem.com what the ratios are.

johnnybayonne · 03-16-2008, 07:53 PM

Quote:

Originally Posted by Antiburn

You will need to change the front subframe, drive shaft, instrument cluster, and possibly redrill rear trans mounts but it might fit. You would want to use the same diff. Auto's tend to have a better gear ratio then manuals which you can find out at realoem.com what the ratios are.

+1
http://www.realoem.com/bmw/select.do

**guilty1** · 03-16-2008, 08:03 PM

Antiburn.
Both cars are 5spd.
I thought both cars used the same body platform?

witeshark · 03-16-2008, 08:18 PM

They do, but sub frames and mounting points will be a lot different between a 4 and a 6 inline.

**guilty1** · 03-16-2008, 08:26 PM

I have the cross member from the sedan..but what you are saying is that the cross member may bolt in a diferent location on the sub-frame?

witeshark · 03-16-2008, 08:58 PM

It's possible.

**Antiburn** · 03-17-2008, 05:34 PM

The only difference that Im aware of with the subframes is that the engine mounts are different from 4 to 6 cyl. The 4 main mounting holes should all line up with no problem.

The issue with the rear trans mounting holes is that the 4cyl trans could possibly be shorter, but knowing BMW from that era almost everything is interchangeable. Easyest way to find out before dropping eather trans's is to measure from a given point off the frame rails.

**guilty1** · 03-17-2008, 09:07 PM

Thanks Antiburn!
I tried the link to the realoem.com but it did not give me the specs on the rear final drive ratio,
Do you know of a site that may have this info??