Re: Physics is....

[Josh Pinkert <flush@us.net>]

At 10:42 AM 3/10/98 -0800, Orin Eman wrote:
>
>Quite true, it is not a binary switch, what you say is absolutely
>correct _if the shafts are turning at the same speed_.
>
>I said 'if there is any speed differential'... for there
>to be a speed differential, all the friction surfaces must in
>the torsen must be slipping, therefore all frictional forces must
>be at their maximums, therefore torque split is at the maximum.
>
>If then max torque split is more than one shaft can take, it spins of course
>and speeds up to the speed of the faster axle.  Once it reaches that
>speed, then torque will probably go to the other axle.
>

Exactly, and this is the crux of the *bite* that's been described.  But
what MOST Torsen defenders claim is that it's unlikely to have a car start
out in an oversteering condition with a 30/70 split (F/R) and have the
torsen flip flop entirely to a 70/30 split.  Once the rear tires reach the
same speed as the front tires, the torsen will likely equalize it's torque
split.  The car may still be oversteering, but I claim the car will become
very neutral.  But why would one assume that the torsen will overcorrect
and induce understeer?  You're right about the torsen being dumb...there's
got to be something else going on.  Maybe the type 44 (with the large
overhangs and boaty suspension) will have nasty suspension undulations and
changing chassis dynamics...therefore resulting in the torsen reacting to a
bobbing car.  I can see how that could occur.  That would also explain why
the smaller cars have a lower incidence of torsen bites.


- Josh Pinkert
- Josh@Pinkert.com
- '98 A4q 2.8
- ISO '70-'73 Porsche 911