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Limited Slip Rear Differential Lock

Rip

New member
Joined
23 Jul 2008
Messages
15
So, having decided that Guards Red would not be a huge faux pas, before I finally order, the one item I'm not sure on is the rear LSD lock (997 TT).

It's just about the only item that doesn't have an info button on the Porsche configurator.

I know what an LSD is and why I'd want one.

I also know what a diff lock is and why I wouldn't want one in a Turbo.

I'm assuming the LSD lock just locks the LSD part and not the whole diff. Is that correct?

Is it pushbutton operated and individually selectable or combined with Sport mode?

What is the benefit? :?

All advice appreciated.

Oh, and tell me the PCCB really are wrth the extra. :shock:
 
Locking differentials

Locking differentials are another derivative of open differentials but with an electronic, pnuematic or hydraulic actuation system that locks the two drive pinions together as if they were a solid axle. This is for use in serious off-roading, where a vehicle will spend a lot of time with one wheel per axle in the air. By locking the differential, it behaves like a solid axle and both wheels are spun together.
The exceptions that prove the rule

Remember I said that there were a couple of exceptions? A good example of a vehicle with no differential would be a NASCAR or Indy car racer. To save weight, those cars have no differential. "Ah yes," I hear you say, "but they go around corners so they must have differentials!". Well - yes, and no. With the exception of street courses, NASCAR and Indy car racers always turn left, and this is Good News for the engineers. When you know that a vehicle is always going to be turning one direction, you can make the outer tyres physically larger than the inner ones. This gives them a greater circumference, and that in turn means that for every turn of the axle, the outer tyre is going to try to travel further than the inner one - precisely what you need in a corner. For the straights, these racers live with the scrubbing that happens when the tyres tyre to travel different distances because 90% of the time they are cornering.

Source - http://www.carbibles.com/transmission_bible_pg2.html

[edit]

PCCB - I suppose if you track it, then yes, if not, then no. I'm not sure you get your money back when to come to get rid?
 
ResB said:
PCCB - I suppose if you track it, then yes, if not, then no. I'm not sure you get your money back when to come to get rid?

:yes:
 
Rip said:
So, having decided that Guards Red would not be a huge faux pas, before I finally order, the one item I'm not sure on is the rear LSD lock (997 TT).

It's just about the only item that doesn't have an info button on the Porsche configurator.

I know what an LSD is and why I'd want one.

I also know what a diff lock is and why I wouldn't want one in a Turbo.

I'm assuming the LSD lock just locks the LSD part and not the whole diff. Is that correct?

Is it pushbutton operated and individually selectable or combined with Sport mode?

What is the benefit? :?

All advice appreciated.

Oh, and tell me the PCCB really are wrth the extra. :shock:

Isn't it just a mechanical LSD rather than PSM 'attempting' to do the same. Personally speaking I'd rather have the LSD and let PSM deal with what it should be doing......that is not coming on when cornering at speed or accelerating way on uneven surfaces.
 

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