I stumbled on the BMW forums n i've been reading a bunch about people switching the differentials, and adding in a LSD (limited slip differential). Now i'm not that great at this... so can anyone explain how they are able to give gains and why is there so few talk of these on Mercedes. I know kleeman makes LSD for their kleeman models... cept i thought this was mostly for automatic transmission to achieve wheel slip. So how would it help out for a manual transmission where we are already able to achieve wheel spin.

 

An LSD is good for everything! You got a little mixed up, and LSD prevents wheel spin. An LSD forces the wheels to get equal power. They can give gains because under heavy acceleration with an open diff all the power will go to the wheel that spins the easiest, ie the wheel with less traction. That gives you wheel spin which we all know is lost engine power. Having and LSD forces the engines power to go to both wheels. Now instead of having all the power go to one wheel, each wheel is getting half the engines power. Since loss of traction is a function of the torque applied, decrease the torque by half and you have less wheel spin, ie better acceleration. (This is more noticible obviously on cars with lots of power) An LSD is also better in any situation where there is low traction such as rain, snow, gravel etc... It also helps in handling too for the same reason... And yes it would help in a manual, especially since you can drop/slip the clutch giving more torque quicker than you could do in a automatic. You can tell if a car has open or limited slip by looking at the skid marks, an open diff will only have one and a LSD will have two (Or four if you saw that blown Jeep Grand Cherokee H.O. 4.7 with a Belle SC, that was nuts!!! Crazy to see 4 smoking tires on one car thats not on fire!)

 

So would the c-clas have a LSD... cause i see 2 skid marks :p

 

No, pretty much all modern MBs are open diffs, with a "simulated LSD effect" from the ASR system. It modulates brake pressure(even during accelleration) to keep equal power to both wheels. It works great it slippery weather, like when youre trying to take off in snow, provided youve slapped the ESP button first.

Go do a burnout in Dyno mode. It should leave one streak.

 

On several occassions, my wifes former ride, a 4.7 V8 JC would spin all four if you got on the gas hard. Usually after it had been washed, and the tires were free of grit and cold(not wet), it would light them up nicely. Quite a site, and sound.

 

wow, man...I thought LSD went out with the 60's, man.....
(oh...you meant Limited Slip Differential - as in posi-trac - BIG difference)

 

LSDs are great- so why doesn't MB/BMW offer them?

 

Cost savings!!! That is the only reason they are no longer even an option. Although you can take any diff and swap it as long as someone makes it! I would love to get one as my right rear tire is more worn that any other on the car and is always the first to go! Sucks really since if they had a true LSD that would cause a more equal wear on the rears!

 

WOW... and all this time, I thought ESP / LSD was
psychadellic mindreading !