Driveshaft question: b27 to b25 swap

[phenryiv1]

I have an '87 325 (e, though it does not actually say it) with a 5MT and am looking to do a b25 swap into my existing chassis.

When swapping an M20B25 into a b27 car (of the same year- both 1987) that were both 5MT cars, do I need the B25 driveshaft or will the B27 driveshaft work? I was going to get just an '89 B25 motor and put it on my B27-based trans, but I found a B25 with trans and a new clutch for about $200 more then the motor alone. Plus it is an '87, which makes the wiring easier.

Do I need to source the driveshaft from the donor as well, or will my existing driveshaft work?

[jlevie]

The drive shaft for both variants is same.

[reelizmpro]

Beware, if your base 325 trans has the large output flange, you will need to swap that onto the 325i trans so you can reuse your driveshaft. OR get the revshift large/small guibo that allows you to bolt a large flange to small.

[phenryiv1]

Beware, if your base 325 trans has the large output flange, you will need to swap that onto the 325i trans so you can reuse your driveshaft. OR get the revshift large/small guibo that allows you to bolt a large flange to small.

I could not find that on their site- just straight small/large replacement guibos.

[reelizmpro]

I could not find that on their site- just straight small/large replacement guibos.

Contact them, I know they have it.

[John@Revshift]

Here you go

https://www.revshift.com/shop/24v-swap-e30-bmw-flex-disc.php

[MR 325]

If your driveshaft has the large guibo just swap the flange to the other transmission. Easy as pie and a good reason to do the output seal.

[phenryiv1]

If your driveshaft has the large guibo just swap the flange to the other transmission. Easy as pie and a good reason to do the output seal.

I did more research on the options and this is my planned route.

Thank you!