Manual Conversion Vs Slush Box

[tibbs.james 1]

Hi guys

Im new to these forums and have had my face lift E30 320i for 6 months now and while its down getting the head rebuilt i have some questions about transmissions.

1) How much of a thrashing can the auto box take before it gives up

2) Are they pricey to have rebuilt and does somebody have a cheap spare laying about?

3) providing the gearbox came from a M20 engine can i use it in my E30 and still have the shifter/linkage line up.

4) is the drive shaft from the Auto too short or too long to be used with the manual gearbox, and i assume the auto drive shaft has the incorrect yoke ?

i understand the Getrag 240 was the factory manual gearbox for these cars what other models are known to work

Current Slush box is just fine but i have a feeling its the next on the list now that the head gasket is leaking

also is there any good things to do while the cylinder head is off the car ? ( aside from hardness test, skim and valve seating )

If somebody can recommend a mild cam grind to go with that would be great..

ahh piss this post is in the wrong section can this please be moved to the general section

Edited April 11, 2007 by Jimmy

[bravo 34]

1)Not alot.

2) Yes - cheaper to have a secondhand one swapped in. Manual conversion worth the cost esp. if you can do the work yoursellf.

3) shifter will line up fine.

4) auto propshaft front section too short. Should replace entire shaft with secondhand one though not just front part as they are balanced as a single unit. Yokes are the same on all the boxes.

Getrag 260 is bigger stronger and bolts up. same clutch etc as 240. Different shifter mounting frame/arm length and propshaft length as it is longer then the 240 but shorter than the auto. Still lines up fine.

Getrag 240's hard to get now as most are snapped up for use in BMW race series as hey are the only ones allowed. secondhand 260 conversion "kit" is around about $750+

Couple of threads on here that will answer most of your questions.

Edited April 11, 2007 by bravo

[antony 0]

umm...so how much of a big deal is it if your missing the second half the drive shaft for the conversion?

[Silver Fox 43]

Guessing you mean you have the manual front and an auto back half. It will work, but you should get it rebalanced, there are places around where you can get it done.

[antony 0]

yeah; manual front, auto back

still haven't put it in yet tho.

cheers

antony

Edited April 11, 2007 by antony

[Silver Fox 43]

You may fluke it and it could be OK, but if you notice any vibrations in the car, chances are that's what it will be.

[Hartage 0]

If you are mixing and matching the drive shafts, they will work, but make sure that you orientate the yokes the correct way.

Yokes in the incorrect phase will mean vibrations.

[tibbs.james 1]

Thats good news on the driveshafts

But it looks as though getting any manual conversion parts at all will be very difficult

[bravo 34]

Not true - every couple of months whole conversions appear on trademe. I have bought three in the last 18 months - all for $750 or less although prices are rising.

[Silver Fox 43]

Check the f/sale, I have one that will bolt straight up for $600, all the important parts.

[willyuka 0]

If you are mixing and matching the drive shafts, they will work, but make sure that you orientate the yokes the correct way.

Yokes in the incorrect phase will mean vibrations.

True that, I have to pull mine apart again to ''orientate the yokes " because of new vibrations from new hanger bearing install. Could you elaborate for me please? Do they have to match orientation front to back??? I'm new at BMW tutu-ing. Thanks.

[bravo 34]

the u-joints should be oriented opposite. A u-joint "speeds up" and "slows down" as it turns (as opposed to a CV joint which doesn't - Constant Velocity Joint)

If they face the same way you get increased speeding up and slowwing down hence vibration. The need to be opposite so they cancel out. That means that the u-joint yokes at either end of the prop shaft should be in the same plane and the yokes that attach to the gearbox and diff should be in the same plane.

A picture is worth a thousand words here.

Edit: stolen from wikipedia:

Edited April 14, 2007 by bravo

[willyuka 0]

the u-joints should be oriented opposite. A u-joint "speeds up" and "slows down" as it turns (as opposed to a CV joint which doesn't - Constant Velocity Joint)

If they face the same way you get increased speeding up and slowwing down hence vibration. The need to be opposite so they cancel out. That means that the u-joint yokes at either end of the prop shaft should be in the same plane and the yokes that attach to the gearbox and diff should be in the same plane.

A picture is worth a thousand words here.

Edit: stolen from wikipedia:

Thanks for your time answering my Q, will get into it again sometime and update you on how I get on.

Thanks again Bravo.

BEM3W4

[willyuka 0]

Thanks for your time answering my Q, will get into it again sometime and update you on how I get on.

Thanks again Bravo.

BEM3W4

I had another look under there and the drive shaft is correct from the trans to the hanger bearing but the second half by the diff has a cv looking arrangement and no yoke. So, I took it apart and lined up front shaft balance weight with back half balance weight and then see what happens. Better than before, 0 upto 50 k's fine, 50 to 70 wee slight vibration still noticeable, 70 and beyond all good no vibrations. Will pull it apart again and keep adjusting til i get it right. Thanks.

[bravo 34]

Next tim eyou pull it apart, take a photo and post it up - I'm intrigued.

[kerrynzl 3]

I had another look under there and the drive shaft is correct from the trans to the hanger bearing but the second half by the diff has a cv looking arrangement and no yoke. So, I took it apart and lined up front shaft balance weight with back half balance weight and then see what happens. Better than before, 0 upto 50 k's fine, 50 to 70 wee slight vibration still noticeable, 70 and beyond all good no vibrations. Will pull it apart again and keep adjusting til i get it right. Thanks.

Not only does the U joint have to be phased back-to-back so the velocity at each end is constant, the angles of the driveshaft at each end also have to cancel each other out: The Engine/gearbox centerline has to be parrallel to the pinion [under load]. on old leaf spring cars the diff was angled down about 2degrees to counteract spring wrap-up.

The inclining of the drivetrain is the most common mistake in engine/gearbox swaps

What you mentioned above sounds more like a slight misallignment than a balance problem [it goes away at higher speeds] Try shimming 'up' the rear of the gearbox or 'down' the rear crossmember to see if this helps.

If you never had this vibration before,and are still using the old rear D/shaft ,then the problem is in front of the hanger

[incidentally both halves of the drive shaft should be balanced separately]

[Silver Fox 43]

Hey bravo, I've got a 4.1 med case diff with a flange for the cv shaft, and the drive shaft with the cv joint on the diff end as well, 6 bolt circular plate. I was told it's out of a manual E30, the drive shaft measures up at 1540mm o/a from flange to flange, any idea what it's from. Will post pics later.

[Silver Fox 43]

Pics of cv on end of driveshaft, can anyone help with identifying the car it's from?

[ED1RTY 2]

looks freakishly different to any e30 one ive seen