Fitting a twin ear diff cover

[ross_jsy]

Plan on fitting a twin cover diff plate and wondering how people go about it? I believe an e36 plate simply bolts to the diff but the speedo sensor hits the toothed disc. Is it just the sensor that hits or does it hit the cover itself? Have seen people make a 10mm spacer. But if it's just the sensor that needs moving out I am thinking of getting a threaded spacer machined up that will bolt into an opened up threaded hole in the diff with an internal thread to accept the sensor, spaced out 10mm.

Would this work or am I missing something?

Ross

[russ325i]

Do you mean the E36 type Ross? I'm guessing you'll be fabricating your own mount to bolt up to the other 'ear' on the diff cover plate?

If we're both on about the same thing and you manage this would I be able to come and take a look at some point? I think I'm only up the hill from you (I spotted your E30 on the driveway as I passed a couple of months ago) and as E30 188 casings seem so thin on the ground over here at the moment getting my E36 4-plate to fit would be a bonus...

Cheers!

[ross_jsy]

Hey Russ are you on the Channel Islands e30 owners thing on Facebook? I've just posted up about it there, motorhole has pm'd me as he thinks he has a CAD file for a spacer in which case I'll get some machined up, if not, my friend is a CAD designer so I'll get him to knock me some up.

But it's not to fit an e36 diff, just replace the e30 back plate which only has a single ear with an e36 one which has two. My cars being built for the hill climb so worried that repeated hard launches on semi slicks is going to crack the mount and I want to future proof the car as I'm rebuilding the back end so might as well while I'm at it. It would also need extra mounting points welded onto the rear cross member.

If I were you I would stump up for a medium case LSD off one of the traders on here, although shipping seems to be getting rather expensive lately now Ferryspeed shut down!

Was that on Tower Road? If so I've moved but feel free to come look and I can talk you through it if you are interested

[russ325i]

Hello Ross, got it - we're on the same page now!

Long gone are the days when you'd know at least 3 people over here who had one or two E30 diffs kicking around in their sheds hey?! Rebuilding it into an E30 casing has always been the plan but as it's a 4-plate there might be some machining involved so I'm torn as to which route would be easiest. I'm not really up for shelling out for a complete E30 LSD at the moment as I've got two E36 188mm LSDs in the garage and it's the 4-plate one I'm keen to use in the E30.

I'd considered swapping just the rear cover but as far as I'm aware it isn't a direct swap between the E30 and E36 covers, unless it's just the speedo sensor issue that you mentioned which gets in the way? I've heard an E28 medium case diff can take an E30 rear cover but if it's not too much of a ballache to get an E30 cover to go on my current one that'd definitely save on postage.

Yeah it was Tower Hill where I saw you - I'm pretty sure we chatted briefly in the Romerils car park a few years ago (I was in a black 328i Sport), you've gone down the M50 route, right? I know three of the previous owners of your Sport so I'd be interested to see how you've been getting on at some point, I'm on the Facebook group so will track you down on there at some point!

Cheers,
Russ

[ross_jsy]

Iirc the e36 diff doesn't bolt up to an e30 subframe. There is a zoner called Gareth who would be able to help you with building it into an e30 case though.

I remember! Michaels old e36. Did you manage to sell it in the end? I was very tempted, good price for a cool car!

Sweet man keep me posted

[harry_p]

No, the e36 diff casing is completely different. They have a single mount at the frot of the diff off to one side, and the two ear backplate.

E30 diff is bolted down into the top through the subframe, plus the single rear ear.

I don't think you'll ever get an e36 casing on there without major major surgery!

[maxfield]

If you have a search on the Internet Ross, you'll find a few pictures of how people have done it.

But I've never seen an idea that I like. When I do mine I'll be putting into the cage somehow, I haven't got that far just yet. But I'll be building a custom cage.

[GB69]

There is a guide somewhere with lots of pics, I'm planning on doing this next year on mine.

Z3 but same shit.

Pics here http://www.spcarsplus.com/gallery3/index.php/SCC?page=1

http://forums.bimmerforums.com/forum/sh ... t-write-up

[ross2009]

i suppose your refereing to the 10mm spacer i made for mine ross ?

but my diff is a large case for a old m5 i thought the e36 rear cover bolted to the e30 diff hmmmm

[ross_jsy]

I've seen other builds where a plate was used, I'm sure there's a problem using a backplate. I'll do some research when I'm on the laptop

[rich318i]

lol its easy to do ross shocked you dont know how too

[DanThe]

I've seen other builds where a plate was used, I'm sure there's a problem using a backplate. I'll do some research when I'm on the laptop

You can either use a custom made spacer for the backplate, or just change the trigger wheel for one from an E36 diff.
Depends how soft you want it, the easier option is to just build the diff mount into the rear part of the cage, it will be pretty much solid mounted but very strong

[G-Bear]

Winx has a few pics and comments on this job I think. If it's any help.

http://www.e30zone.net/modules.php?name ... g&start=25

[B7]

^^^^^^. Speak to Winx. Henry has this in his touring. A proper nice job as well.

[ross_jsy]

Dan, I thought about tying it into the cage mount but as it's the 16 point bolt in Safety Devices, the rear strut mounts need to be removable.

Is installing an e36 trigger wheel a job I could do without special tools or would it need to go off to say Gareth?

Winx's solution does look very nice indeed, I'll fire him off a PM.

I am tempted to remove the rear wheel well like Ross has done on his build. Replacing this with a removable panel held in with Dzus fasteners or similar would be really handy for access to the diff in the future, but will too much strength be lost cutting it out, or is it negligible?

[ross_jsy]

Actually looking at Ross' build again I like his solution of having the box section welded in and connecting off that:

[ross_jsy]

Thanks for the drawing motorhole, sent it to my mate who is going to look into getting it laser cut for me once he is back from the TT. Anyone know how thick it needs to be?

[gareth]

Sorry lads, should have seen this earlier.

The easiest way to fit the E36 backplate is to also fit the trigger wheel from the E36 diff. The larger E30 trigger wheel will hit the E36 backplate and speedo sender.

Mark everything for position and pop the shafts out, then the bearing caps, then the spool. Don't mix the caps or shims up!!!!!

Tap the trigger wheel off then heat up the new one before tapping on. Once it's on, make sure you get all of the wiry bits of swarf off the end of the spool as these will wreck bearings. If it's hot enough, there shouldn't be any...

Then reassemble with everything EXACTLY where it came from!

Give the casing a good wipe out while it's apart too, they do collect loads of shite in there

[ross_jsy]

Cheers Gareth, and thanks for the PM, I'll get on the look out.

Found a local chap who machines our diffs to receive Ford Motorsport clutch plates (this was second hand info, so might not be 100% correct). Went out in a 325i with one fitted the other day and boy did it lock hard! Might give him a sniff while the diff is in pieces

[gareth]

Ford motorsport use the same clutches as 188mm BMW LSD's. However they used more of them. Chances are he's adding plates