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Re: Torsen Tech

> once again, the (audi) torsen locks the output shafts (no speed differences)
> until it reaches the bias ratio, and then it allows output shaft speeds to
> differentiate, while holding torque at the bias ratio levels.

> hence, before the bias ratio, the torsen is producing the same torque
> proportioning effects as the locker because both are allowing no output
> shaft speed differentiation.  the only input to both devices at this point
> is traction (both longitudinal and lateral grip and slip).

> if you continue not to accept this point, i can see no point in furthering
> this discussion.

Sure, for a perfect world with perfectly flat roads, round tires
with identical circumferences etc..

Unfortunately, real world roads have imperfections which cause
wheels to (try to) speed up a little, slow a little.  A wheel
moving up over an imperfection will require a little more
torque etc..  You could consider this 'noise' in the traction

Now, lets say you are cornering with an average torque distribution
of 38/62 rear.  Now if road imperfections cause no more than 
13% to shift to the rear at any time, then the torsen and locked
center will be indistinguishable.  If not, then the torsen will
be slipping just a little occasionally whereas the locked diff won't.

So, I am in perfect agreement that below the bias ratio, the
shafts are locked.  But, for real world roads, transients in the
torque reactions from the wheels may well cause the bias ratio
to be reached and allow transient slips.  Averaged out, it would
look like you have a little slip at below the bias ratio.

More food for thought...