Limited Slip Diffs

[swanvesta]

hi, first of all, what is the standard diff ratio in a 328i sport coupe? and an e36 m3?
i want a limited slip diff for my 328i and was wondering what ratio to get?
cheers

[jrhaile]

3:15 is what I run and I love it... perfect gearing ratio's

[bad man working]

E36 Dif Ratio:
328i manual = 2.93
328iA = 3.07
328iA USA = 3.91
M3 = 3.15 Limited slip

[93 325i]

I would step up to a 3.46 LSD. The acceleration would be intense. Plus it is still practical for highway use. You can cruise at 80mph in 5th and only be at 3750 RPM. Max MPH would be like 128 at 6K RPM. But hell you could get her up to 150MPH at 7250 RPM but I think that is for M3- the M has an extra grand on the tach..

[wulley1]

what's with the two numbers posted for the auto? How do you know which one you have?

[jshearer]

I don't know anything about limited slip differentials. Who wants to be the educator and give us stupid people a little knowledge. I have guesses about them but, what exactly do they do? How much do they cost? How hard/costly to install? What kind of performance difference?

Thanks to anyone who responds. Although I have learned quite a bit about my car I can always learn some more.

[93 325i]

The larger the ratio the faster the acceleration between gears, but the overall top speed of each gear is reduced. For instance a 3.91 ratio produces neck snapping acceleration, but isn't practical for highway use- the overall top speed is reduced but it will get you to top speed a hell of a lot quicker. YOu can get a used 3.15LSD for about $400. Anything higher has to be custom built and are about $1500. They are not too bad to install- this can even be a DIY if you have the courage. Performance wise a 3.46 LSD and JC chip has been documented to shave at least a second off your 0-60 time

Edit: A custom LSD is the next best thing to do outside of forced induction to improve acceleration. If your like me and rarely go over 100mph this is somehting to surely look into.

[Gkamysz]

LSD allow one wheel of the axle to slip a certain amount before locking up. Basically an open diff will transmit zero toqrue to the tire with traction when the other slips(has no traction). Limited slip will transmit a certain percentage of the total torque to the wheel with traction, even though one wheel is slipping.

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

[dutchbmw]

Mine is 3.23 (Euro e36 M3)

[B_w.]

i have a 3.23 lsd. it is a good improvement over the stock 2.93 and is much more reasonably priced than the more popular 3.38 lsd's. i would get a 3.38 if you have the money.

[nookatee]

where can i find an LSD? Do I have to find one at a salvage yard or find someone on a forum that's selling his/hers?

[97alpineM3]

I've found that the best way to get parts like that is to just search and keep searching... forums... wholesale places... online everywhere till you find what you want...

Good Luck,

Les

[dutchbmw]

You can check out here what happens after a change...... (speeds etc.) http://www.bimmerwerkz.com/forum/index.php...t=0#entry321032