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Having no technical car knowledge at all! :rolleyes: - please could someone explain exactly what an LSD is and how it works?

all I know is everyone seems excited by it - the fact that it improves handling in some way and the fact they can now get it on a S for only £100 extra.

Cheers.
 

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www.totalmini*****
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It's a device which controls the way power is delivered to the wheels.

At the moment the MINI is a 2 wheel drive car. The front left and the front right. If for example the front left wheel breaks traction it will continue to spin, robbing the front right of drive power.

An LSD would only allow the front left to spin a little, keeping power and drive to the front right allowing the car to move forward untill the front left regains traction.

At least, that's my understanding of it.

<--- not a mechanic ;)
 

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Mr 120d Sport
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ButtonIt said:
It's a device which controls the way power is delivered to the wheels.

At the moment the MINI is a 2 wheel drive car. The front left and the front right. If for example the front left wheel breaks traction it will continue to spin, robbing the front right of drive power.

An LSD would only allow the front left to spin a little, keeping power and drive to the front right allowing the car to move forward untill the front left regains traction.

At least, that's my understanding of it.

<--- not a mechanic ;)
Not quite......

From first principles, the differential allows the driven road wheels to rotate at different speeds, while maintaining equal torque on each.

The torque at each wheel is always the same.

If one wheel is on ice and the other on tarmac, the car will not move.....as the torque at each wheel is not the same. Think of it as a pair of scales......equal and opposite.

The purpose of the LSD is to allow for torque to be transmitted in low traction conditions, where without, the car would not move.

Various types of LSD exist. The most popular use friction plates (a bit like a clutch) to allow a degree of slip. The amount of slip can be varied by modifying the clamp pressure on the plates / the number of plates or the material co-efficient of friction.

Robert
 

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ChrisGJ said:
Having no technical car knowledge at all! :rolleyes: - please could someone explain exactly what an LSD is and how it works?

all I know is everyone seems excited by it - the fact that it improves handling in some way and the fact they can now get it on a S for only £100 extra.

Cheers.
Have a look at: http://auto.howstuffworks.com/differential.htm - gives good information about differentials, why they are used, and the different types. There is also generally good information on other aspects of motor vehicles on this site.

Update: also search the forums here there are several others threads about the LSD.

dhm
 

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Could someone explain the diff between the LSD and the DSC and traction control in the Mini. I have a 2004 MC with DSC...does that mean it also has the traction control too?
 

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www.totalmini*****
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DSC is traction control plus a whole bunch of other stuff too. Basically DSC is an electonic management system, when it feels once of the wheels spinning it cuts the engine revs in order to help get traction back.

It also does a whole load of stuff with braking into corners and brake force distribution between the wheels.

Somoene techy will explain soon I'm sur ;)
 

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Mr 120d Sport
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ButtonIt said:
DSC is traction control plus a whole bunch of other stuff too. Basically DSC is an electonic management system, when it feels once of the wheels spinning it cuts the engine revs in order to help get traction back.

It also does a whole load of stuff with braking into corners and brake force distribution between the wheels.

Somoene techy will explain soon I'm sur ;)
I think the DSC bit is controlled via a gyroscope to measure / monitor lateral acceleration (ie if the car starts to go sideways).....it controls the lateral acceleration by using the brakes to slow the wheel slipping and regain control over the laws of physics! (Altough the handbook doesn't quite stat that!)

ASC uses the ABS system in reverse to temper wheelspin, by monitoring wheel speed across the car. When one wheel speeds up in relation to the others. the brake is applied to reduce the speed (ie slip)

Hope this helps.

Robert
(Engineer.........not "techy"!)
 

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wobert123 said:
Not quite......

From first principles, the differential allows the driven road wheels to rotate at different speeds, while maintaining equal torque on each.

The torque at each wheel is always the same.

If one wheel is on ice and the other on tarmac, the car will not move.....as the torque at each wheel is not the same. Think of it as a pair of scales......equal and opposite.

The purpose of the LSD is to allow for torque to be transmitted in low traction conditions, where without, the car would not move.

Various types of LSD exist. The most popular use friction plates (a bit like a clutch) to allow a degree of slip. The amount of slip can be varied by modifying the clamp pressure on the plates / the number of plates or the material co-efficient of friction.

Robert
I knew this thread had your name written all over it Robert !!... lol :D
 

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Mr 120d Sport
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northandy said:
I knew this thread had your name written all over it Robert !!... lol :D
What could possibly make you say that.........:rolleyes: :D :D

BTW I'm now in hydraulics.........working for a supplier of yours!

Robert
 

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Mr 120d Sport
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Anyway, you're the second person to say something similar about me and gearboxes today.......what am I saddo of the year????
 
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