Gearbox compatiblity across models

[TwoTees]

Hi All,
Ive been lurking here for a while but now need to ask a question.
My 16yo son just bought an E30 M40 318i Auto coupe and we want to convert it to manual. We cant find a box conversion parts lot or even a complete M40 doner car for the parts. (there used to be lots but not now)
My question. I have found a 323i manual sedan for a decent price and happy to buy it as it has some other required bits as well and want to know what other parts will be required for the conversion.
I do believe the 323 box will not fit but we seem to have plenty of E36 M40 318i manuals around to pick up a box/clutch/flywheel etc for cheap. The pedals/slave/master cyl/ cross member etc could all come from the e30 323. I'm just not sure if I go down this path I will still be stuck for parts.
Any advice would be great.
Thanks

[Grrrmachine]

It does seem odd that you can't find the swap parts needed - there are plenty of traders on here breaking these sorts of cars. Put an ad in the Wanted section.

As for your parts dilemma: the 323i will provide a pedal box but not much else, while the E36 gearbox sits at a different angle to the E30 ones which buggers up the gearbox mount and shifter linkage. It really would be better to source everything from one car.

[TwoTees]

It does seem odd that you can't find the swap parts needed - there are plenty of traders on here breaking these sorts of cars. Put an ad in the Wanted section.

As for your parts dilemma: the 323i will provide a pedal box but not much else, while the E36 gearbox sits at a different angle to the E30 ones which buggers up the gearbox mount and shifter linkage. It really would be better to source everything from one car.

Thanks for that. Getting a complete car is my preference. I just can't find one locally with in 300km (I'm in Australia) and my son is getting impatient.
When we went looking for a manual coupe they were rare but there were plenty of manual m40 sedans for sale. A manual coupe here is worth 3x a sedan of the same spec so we bought the auto coupe with the plan of converting it. Now the sedans are all dried up and we have been looking for a month.
The 323 has lots of other nice parts we could use but if the conversion parts are no good its not worth it.
I guess we'll keep on looking.
Cheers

[Motorhole]

Why not just swap the entire engine, box & prop etc from the 323i, assuming it's an E36?

[Grrrmachine]

Why not just swap the entire engine, box & prop etc from the 323i, assuming it's an E36?

The pedals/slave/master cyl/ cross member etc could all come from the e30 323.

[daimlerman]

Why not just swap the entire engine, box & prop etc from the 323i, assuming it's an E36?

The pedals/slave/master cyl/ cross member etc could all come from the e30 323.

The engine/'box etc could all come from the E30 323i....

[TwoTees]

Why not just swap the entire engine, box & prop etc from the 323i, assuming it's an E36?

The pedals/slave/master cyl/ cross member etc could all come from the e30 323.

The engine/'box etc could all come from the E30 323i....

Yes I did think of that but I am just not up for that kind of time and pain at the moment.
I like the 318i because it is easy to work on. I did an engine swap on my wifes 325i Cabbi and I don't have enough wrists on each arm to perform the work comfortably
The 323 sold yesterday so we are back to the waiting game.

[TwoTees]

Any of the m20 gearboxes will bolt up to the m40. They will sit at about 10degrees off vertical which is not a problem provided the box has the aluminium gear lever extension. It is easily twisted to bring the gear lever back to vertical. You will need to fabricate a gearbox cross member as the standard one will not work.

This is the gear lever setup you need.. http://bmwfans.info/parts-catalog/E30-4 ... ng_part_2/

Thanks for this great info. So if I could just clarify a few other points if I happen to come across another complete e30 M20 manual doner car.
Are you also saying the e30 M20 flywheel will bolt to the M40 crank therefor the clutch/P Plate will also fit? If not and I need to find an M40 flywheel will the m20 clutch pressure plate bolt to the M40 flywheel?
Starter motor should be from the M20?
I'll need a standard M40 spigot bearing?
Does the box sit longitudinally in the same location. If so the M20 doner drive shaft will also fit?

Also just in case I happen to come across an E36 M40 gearbox the 10deg angle should not be an issue since it is coming from an m40? Right? I didn't quite understand the below post untill you showed your cross member. It makes sense coming from an M20 to M40. But a box taken from an M40 to M40 should be the same angle??
Thanks

As for your parts dilemma: the 323i will provide a pedal box but not much else, while the E36 gearbox sits at a different angle to the E30 ones which buggers up the gearbox mount and shifter linkage. It really would be better to source everything from one car.

[daimlerman]

I think that grrrrrrmachine is getting confused with his M numbers!

M20/M10 are the early range of E30 engines,sit at the same angle.

M40/M42 are the later range and sit at a different angle.Only possible downside to Willnz' suggestion is oil level and filling,you will either have too much oil in or too little,I cannot remember which way it is!

M50/M52 engines are,in effect,a 6 cylinder version of M42,so using an ex-M40/42 'box gets around this problem.

Using an ex E36 M40 'box MAY give rise to diff ratio issues if the 'box is a ZF,as apposed to a Getrag,as the earlier Getrag has an overdrive 5th.

[TwoTees]

Thanks guys. This arms me with the info I need to make a quick decision when something pops up.
Its a pity we missed the 323 then. That was really cheap and had lots of goodies on it. Oh well the next one I'll be ready. Ideally an M40 manual car will be the best option but will grab an M20 if the car is worth the extra effort of the cross member mod.
Cheers.