1994 325ic limited slip diff

[doclees]

Anyone know what models and years I can swap a limited slip diff into my open diff 1994 325ic?

thanks

[svginferno]

you can swap any limited diff that is a medium sized case from any other E36s that have a LSD. These include some 1991-1995 325i(S) with cold weather package or as a separate option, and all //M3s. the most readily available ratios are 3.15 and 3.23. good luck with your hunt. you might have to swap on the input and output flanges from your diff.

[dlduke]

Mr. Inferno, A couple of additional questions: I know LSD's are almost always used in racing cars, but what exactly do they accomplish? Just better traction with both wheels or something additional? I have a 3.15 LS that I want to someday put into my '92 325I.(Came from a '95 I think). A good choice? Any drawbacks to the LS for general driving? Is it pretty much a direct bolt-in?

[328 Power 04]

Mr. Inferno, A couple of additional questions: I know LSD's are almost always used in racing cars, but what exactly do they accomplish? Just better traction with both wheels or something additional? I have a 3.15 LS that I want to someday put into my '92 325I.(Came from a '95 I think). A good choice? Any drawbacks to the LS for general driving? Is it pretty much a direct bolt-in?

Exiting a turn with LSD feels soo much better. It all depends if you're doing performance driving or not. Also you can do 2 wheel burnouts, if you're into that kind of thing. Its pretty much a direct bolt in, except for some flanges you MAY have to swap. There are no known drawbacks. They have put those LSDs into cold weather package 325s to give them better winter traction, where both wheels will spin.

also check this thread about a common failure part inside these diffs, and you should check the bolts inside and locktite them before putting up the differential. It would save you some time later. http://forums.bimmerforums.com/forum/showthread.php?t=390209

[doclees]

Thanks folks,
On to search ebay.

[dlduke]

Thanks from me too. Very useful info; Not that I really needed another project, but the loose bolt deal will have to be addressed before going further.

[doclees]

And to follow up, how many miles do these units last without a rebuild assuming average driving?

what does it take to make a 2.93 open into a 2.93 posi?

[svginferno]

And to follow up, how many miles do these units last without a rebuild assuming average driving?

what does it take to make a 2.93 open into a 2.93 posi?


Mr. Inferno, A couple of additional questions: I know LSD's are almost always used in racing cars, but what exactly do they accomplish? Just better traction with both wheels or something additional? I have a 3.15 LS that I want to someday put into my '92 325I.(Came from a '95 I think). A good choice? Any drawbacks to the LS for general driving? Is it pretty much a direct bolt-in?

Assuming you know how an open differential works. An LSD unit allows the wheels spinning faster on the outside of a turn to apply torque on the wheel on the inside of the turn, such that you have better traction. This way, you are apply power to both wheels as opposed to one. This is why you'd get a one wheel burnout without an LSD. LSDs are a great upgrade for spirited driving. The 3.15 LSD you're looking to put in is a great upgrade. But there are drawbacks. Changing from the stock 2.93 gear ratio to a 3.15, you will get better acceleration, but you will lose your top speed. Also, this will cause a reduction in fuel economy. The LSD unit will cause further reduction in fuel economy. I also have a 3.15 LSD in my 325, and my fuel economy dropped from ~26mpg to ~24mpg for mixed driving. To change a 2.93 open to a 2.93 LSD, you'd have to swap in an LSD unit and readjust the gears in the casing, such that they are properly clearanced. I wouldn't suggest making a 2.93 LSD unless you plan on getting a power-adder, as it is quite a time consuming process.

[angeleus]

make sure to get the Output Shafts that were attached to the differential if it came off an M3. The Output Shaft aka. CV axle is longer for the M3 and thicker at the flange connection. Check www.realoem.com to see the difference

[doclees]

The LSD unit will cause further reduction in fuel economy. I also have a 3.15 LSD in my 325, and my fuel economy dropped from ~26mpg to ~24mpg for mixed driving. To change a 2.93 open to a 2.93 LSD, you'd have to swap in an LSD unit and readjust the gears in the casing, such that they are properly clearanced. I wouldn't suggest making a 2.93 LSD unless you plan on getting a power-adder, as it is quite a time consuming process.

So if I drop down to the 2.93 ratio but do the FDM and change the air intake to a K&M style snorkel will the power feel about the same as now?

Any reviews on the OBX LSDs? I haven't read any great reviews but can they be made serviceable?