e30 diffs

[flake 0]

stupid question.

is it possible to swap the center of a mid case LSD into the small case of an e30 diff?

probably not but thought i would ask.

and if not, can you swap to the whole mid case diff into an e30, odviously this would involve altering the subframe. but surely there's a way around that cause didn't some e30s come with mid case diffs?

thanks

Edited February 27, 2010 by flake

[Silver Fox 43]

Med case diffs will fit all E30's. Centres do not swap from med to small.

[_ethrty-Andy_ 2122]

i have a medium case LSD in my 320i (comes with small case from factory). the medium case diff actually bolts straight up surprisingly

Edited February 27, 2010 by ethrty320

[flake 0]

anything to look for with the LSDs eg: wear and tear, missing teeth, spider gears welded?

the diff outputs both spin the same way so i presumed it was a slippery, i'll just have to take it apart to double check it hasn't been locked

[pureboiracer 0]

if it is a medium case and both outputs spin the same way, also try turning the 2 outputs opposite ways, you shouldnt be able to. then it will either be locked or lsd, take the cover off the back and if you cannot see any spider gears then it will be lsd, as the lsd looks like one big casing where the spider gears go.

Aslong as it doesnt feel really rough when turning it and that there is not alot of freeplay in the pinion shaft then it should be ok, lsd units dont tend to wear much or brake.

[flake 0]

thanks guys, i'll give it a go tomorrow and let you know how i get on.

otherwise it'll be out with the mig

cheers

[_ethrty-Andy_ 2122]

have fun! diffs are PITA to do imo. heavy awkward bastards and hard to balance on a jack and menouver into place. time of your life ahead haha

[tibbs.james 1]

I had both med Case and small case in that car Flake,

Your Car has proper 325 Axles from Ray at hell bm , med case is direct fit where the small case was

[Jono51 58]

thanks guys, i'll give it a go tomorrow and let you know how i get on.

otherwise it'll be out with the mig

cheers

don't lock it, if you do this can create wof issues

I've got an LSD Medium case diff if you are interested

cheers

Jon

04 3801 089

[e30ftw 396]

You can look through the speed sensor hole and see if it has spider gears or not. Not sure how well that works when the diff is in the car though, But either way diff is real easy to pull out.

[flake 0]

ok so what i presumed was a LSD was infact a locker.

first clue was the subframe and diff mount nuts and bolts were hand tight. subframe and axles were dirty as hell yet the diff was spotless which made me think it had been out of the car, cleaned and welded.

my plan now is to run with the open diff for a while and wait till a cheap LSD pops up. i dont want to have to pay $700-$1000 for one so i'll join the cue of e30 owners who are hoping to get lucky and pick one up from the wreckers who dont know sh*t about what they're worth.

this guy who was a friend of a friend of a friends friend also had a "limited slip differential" out of an e32 735i with the early style hydrolic brake booster. surley im not blind but this one had 8 bolts on the diff output to alxe flange. would this be a 'large' case diff? ie: small case - 4, mid case - 6.

does anyone know much about these larger case diffs?

[pureboiracer 0]

yeah it would probably be a large case diff.

IMO you will be better off running with the locker in your car than the open. It would be alot more predictable.

[_ethrty-Andy_ 2122]

i wouldnt run my car in mine as i like to know my car is 100% legal. That said, (how) does a WOF shop actually tell if its an open/LSD/locked diff? ive never seen them check that at VTNZ before (market themselves as the most thorough and reliable...)

[Linden 0]

I went for a WOF with my last car and while he had it up on the lift he spun both the back wheels if it was a locky im sure he would have noticed. then again he passed the WOF with a 2.5 engine conversion (ex 1.8)

[e30ftw 396]

Hard to tell.. For an e30 they can come with LSD' so they wouldn't know if it were LSD or locky really. But a lock diff sucks to daily drive with anyways...

[tibbs.james 1]

Sticky tires and an open diff does pretty well

[pureboiracer 0]

i drove a e30 m52 with an open diff and some good tyres on it and it was horrible tbh. It was super unpredictable and you could not use the power at all. I think you would be safer with a locky, aslong as you are prepared for it to skip out around fast corners and dont mind radical tyre wear. The locky will be very impractical but having a single spinner in a car like that is just pure dangerous.