LSD Question/ Comments

[AutoXfreak]

I was wondering if any e30's came with LSD's? If so what models and where and how much could I get one for. If no E30 came with one wht would you guys recomend to use. A clutch type a gear type or anyhting else. The car is an 86 325e and is a daily driver but will see heavy AutoX use and a few track days.

Thanks!

 

[mrferg]

The 325is came with one, look on ebay or at junkyards.

 

[rjp325i]

LSD was standard on all 325is models and optional on the base "i" model as well as optional on the 1984-85 318i. My old 318i automatic had a 4.10 lsd and my 1989 325i a 3.73 lsd. Many of the base "i" models had the lsd included from the factory so they are not too hard to find. The "e" models used either a 2.79 or a 2.93 depending upon year. I know the '85 "e" carried a 2.79 and the '87 "e" a 2.93. Those specs are from that years sales brochures. I do not have the specs on the 1988 super eta as it was known nor the later 318is models.

 

[ODDferkOUT]

Pardon my ignorance to it and all...

...but what exactly does a Limited Slip Differential do to a RWD car. I mean, I have an idea, but - eh - what is the general explanation to it's purpose. Did the 325iC come with one?

 

[rjp325i]

In very simplified terms: A larger proportion of the power is directed to the wheel with the most traction when a loss of traction is encountered by one of the drive wheels. You can tell if you have lsd in a couple of ways. The first way is simply look for a metal tag on the diff that says it has lsd. Second is jack up the rear of the car or place the car on a lift that will allow you to move the wheels. If when you move the wheels both wheels turn in the same direction you have a lsd. If they turn in opposite directions you have a standard setup. Another way is by disassemby and actually seeing the clutches inside. I do not know about it being standard or optional on the ic as the 325ic sales brochure I have does not mention it one way or another.

 

[AutoXfreak]

Cool, thanks for the feedback, I wanted an LSD for my car but being in college I dont have the vast loads of cash to spend on a new one.

 

[benm]

Check out www.howstuffworks.com's article on differentials. They have some great explanations, with some *excellent* animations. I highly recommend reading it.

http://auto.howstuffworks.com/differential.htm

Hope that helps.
-Ben

 

[jrt67ss350]

In very simplified terms: A larger proportion of the power is directed to the wheel with the most traction when a loss of traction is encountered by one of the drive wheels. You can tell if you have lsd in a couple of ways. The first way is simply look for a metal tag on the diff that says it has lsd. Second is jack up the rear of the car or place the car on a lift that will allow you to move the wheels. If when you move the wheels both wheels turn in the same direction you have a lsd. If they turn in opposite directions you have a standard setup. Another way is by disassemby and actually seeing the clutches inside. I do not know about it being standard or optional on the ic as the 325ic sales brochure I have does not mention it one way or another.

Or, you could just go the more destructive route and do a burnout - if both rear wheels spin and you leave two black marks, you have a LSD.

 

[Rukus]

IS this normal for an LSD? i was driving up the hill in town here and it was icy out last night. So naturally, traction was at a minimal. Is it normal for when the car loses traction and then finds it again, for the Wheels to slam as they catch traction? I am thinking it would be normal, because if one wheel spins and it gets traction all of a sudden it is going to "pass the power into " the wheel with the more traction and wait for the other wheel to "catch up"

so this should be normal?

 

[xLibelle]

do a donut, if it looks like this, its not locking diff.

 

[Rukus]

i KNOW mine is an LSD, i had it apart, the tag says LSD and when you spin the axles, they spin the same direction. I just bought it and put it in less than a month ago.

I just am not used to those things after driving open differential for my whole life.

 

[AutoXfreak]

What style of LSD does BMW use? Is it a clutch type or a gear type and which one of the Diffs is better and why?

 

[Rukus]

i beleive its clutch type.

Hows does a gear type work?

 

[AutoXfreak]

The gear type is like a "quafe" (sp?) diff. It uses a central gear with sun gears surounding it. They tend to lock up a lot quicker, I realy only know of them being used on front drivers but I think would also be used on rear too.

 

[Rukus]

yeah these are clutch types. i know that for a fact.