My 323i Race Car Update

Duracel79 · Post by **Duracel79** » Wed Feb 25, 2009 11:50 am

Well,

I've been sorting out my spare differential to replace the one in the car.
For now a standard 3.45:1 BMW LSD with standard lockup. Had my transmission man check it all over and set up the backlash etc.

Today I removed the diff from the car that I felt was suspect. It is an 3.45:1 LSD but with both wheels jacked up the wheels didn't turn the same direction unless using very small pressure.

I took it all apart and what did I find but a Quaife LSD!!

Now that was a surprise find.

These run without plates, just gears so do not feel the same. the standard lsd test doesn't work with them.

Oh well I think i'll use the standard BMW unit for now and build the Quaife into a diff with lower ratio's.

Duracel79

tommi_e21 · Post by **tommi_e21** » Mon Mar 23, 2009 3:30 pm

how much does a quiafe lsd cost these days???? me thinking quite a bit

Duracel79 · Post by **Duracel79** » Mon Mar 23, 2009 9:19 pm

Don't know the cost but the one found in my car is the same as fitted to E36 318i's and Z3's. I phoned them up to check what it was and how it should feel.

Bit of progress, my dad and his Dutch friend may have sorted out fitting the E30 4.1 ratio crownwheel and pinion into the E21 casing for me. Just needs blue-ing up to check the meshing but it feels OK.

I'll post up details of the bearings and shims needed for this conversion when I know it works well.

Duracel79

tommi_e21 · Post by **tommi_e21** » Mon Mar 23, 2009 9:50 pm

sounds like good work! look foward to the report

charbel · Post by **charbel** » Mon Mar 23, 2009 10:51 pm

so there is a LSD without plates for the e21?
that is interesting.. a picture will be nice. i had the yellow alpina i part out and it did now have a LSD as far as i know cause the wheels will not turn in the same directions..

anyway.. e28 diff you can use in an e21. same distance for the axles and same axles bolt patern. so all you have to do is mounted on your subframe .. i am not saying easy.. but it is easier then trying to fit any other diff in that car.. i know the e24 635 also fit on the e21. i have done it before..

good luck with the car

Jason_323i · Post by **Jason_323i** » Mon Mar 23, 2009 10:52 pm

Qualifies are about 700 plus vat

Jason

tommi_e21 · Post by **tommi_e21** » Mon Mar 23, 2009 10:53 pm

is that 700 include all the casing or just internals to put into your own casing

Jason_323i · Post by **Jason_323i** » Mon Mar 23, 2009 11:06 pm

That's just the internals

Jason

Duracel79 · Post by **Duracel79** » Mon Mar 23, 2009 11:11 pm

Jason_323i wrote:That's just the internals

Jason

Just why i was so pleased to find one in the casing

tommi_e21 · Post by **tommi_e21** » Mon Mar 23, 2009 11:50 pm

prob another dumb ass question, are the externals same on open to lsd,s, eg if i bought quaife internals could i fit them in my open diff

Duracel79 · Post by **Duracel79** » Mon Mar 23, 2009 11:58 pm

Yes, all fits.

Just need to swap the crown wheel and output bearings off the open diff and fitting them onto the LSD. It would be worth checking all the cearances once fitted together though.

I did a similar swap on my E30. There was a bit of play so I thought it would be OK. Done about 40k since and the diff has started to wine at around 60mph. Not too bad considering its got a strong 2.7 driving it.

Duracel79