E30 Zone

hello everyone just got my first e30 a few weeks ago & it has a welded diff,i dont like it has any1 out there got a L.S.D for sale for a good price not a rip off like alot i've been lookin at.

LSD in good order will cost in the region of £250....

It would help if we knew which E30 you own and the ratio you are seeking!

an LSD in good order for £250 is getting VERY hard to find now malc

Budget £350 at least for a good one, depending on size and ratio.

What's the car/engine?

gareth wrote:an LSD in good order for £250 is getting VERY hard to find now malc

Budget £350 at least for a good one, depending on size and ratio.

What's the car/engine?

It's me age,Gareth!
Things were always cheaper back in the dark ages....

Right i'm not to clued up on ratio's & stuff yet but the engine in my e30 is a 325i with a stainless steel system it was originaly a 320i

A 320 would have had a small case diff with a ratio of 4.1....

You really need a medium case diff with a ratio of 3.64 or 3.73.

How do you identify a diff?

a)ratio will be stamped on a tag attached to a back plate bolt
b)size is best worked out by the number of bolts that hold the back cover on,small has 6,medium has 8.

Side by side,the size difference is easy to spot,from under the car,this is less easy to see.
The diff sizes are interchangeable between E30,the bigger unit just needs the prop shortening by about 13mm at it's centre joint.

Still confused on ratio choice?

4:1 gives 65mph at 3000rpm
3:64 gives 73mph at 3000rpm

These fiqures assume 5 speed manual gearbox.

Nice one mate, yeah sounds like i have a 4.1, do you or do you know anyone that has a medium case slip diff with a ratio of 3:64?

AliE30 wrote:Nice one mate, yeah sounds like i have a 4.1, do you or do you know anyone that has a medium case slip diff with a ratio of 3:64?

i offered you a 3.64 lsd in your wanted ad.

oh did ya lol sorry mate haha i'll have a look.