Limited Slip or Posi Rear End Question

HB_Cobra · #1 (**permalink**) 10-07-2011, 08:08 PM

I assume someone else has run into this. Currently my back draft cobra has a one legger BMW 3 series rear end. I was told only back draft sells something to get it to limited slip, which cost 1400. Does anyone know what other rear ends fit in there like a 5 series BMW which is sold in limited slip?

CHANMADD · #2 (**permalink**) 10-07-2011, 09:49 PM

The M 3's all have clutch type limited slip diffs.

SkipB · #3 (**permalink**) 10-08-2011, 08:31 AM

First concentrate on the E36 series cars for what you want. As mentioned I believe all E36 M3s came with limited slip. Also the cars equipped with the sports package did as well. This means you can often find a diff from a used or junked car. Lots cheaper, but you do run the risk of unknown mechanical problems. In any case a limited slip diff from the E36 (1992-1999?) series should bolt right in.

You can also search for these online and there are several vendors that can supply a rebuilt unit. But, the price is in the dealership range.

I am not too sure you will feel any difference after you install one. The open diff from Backdraft (again E36 series BMW) is pretty stout and can handle lots of power. I guess if you decide you want to leave two black stripes instead of one when you do a burnout, then a limited slip becomes important.

SkipB

D111 · #4 (**permalink**) 10-08-2011, 02:05 PM

e36 BMW M3 3.46 LSD Limited Slip Differential | eBay

HB_Cobra · #5 (**permalink**) 10-08-2011, 09:42 PM

But from what I have been told the M3 has a rear end from a 5 series. Which would mean I could use any rear end from a 5 series as long as it was limited slip…..right?

SPF1061 · #6 (**permalink**) 10-09-2011, 08:09 AM

Quote:

Originally Posted by SkipB

I am not too sure you will feel any difference after you install one. The open diff from Backdraft (again E36 series BMW) is pretty stout and can handle lots of power. I guess if you decide you want to leave two black stripes instead of one when you do a burnout, then a limited slip becomes important.

SkipB

...or if you want to be able to charge hard out of a turn and onto the straightaway on a road course rather than spin the light drive tire and go nowhere fast....

If you just want to street cruise and do car shows, save your money.