Torsen thread

["Lawson, Dave" <dlawson@ball.com>]

Phil,
>
> ... IF this bite is something that can be induced in a torsen car,

Are all the 'TORSEN centre' cars also 'limited-slip rear' cars?
>
No, in the US we have an open diff which can be locked by pushing a
button. A electro/vacum servo is used and the rear diff automaticaly
unlocks at 15 mph. It gets the speed signal from the ABS/dash,
white/blue wire on my 1990 200 TQW.

This is one big difference I see betweeen what we have in the US and
what the fiche shows. In all my digging for info on the ur-q, I heve
never seen a rear limited slip mentioned in any published article. If
anyone has seen a reference to an LSD on an ur-q, please state the
source. But then your mentioning of the fiche, and sure enough, it says
limited slip differential. In general you can't really trust the
drawings on the fiche, but in this case it does appear to show a rear
case which is different and the parts list is different. I did notice
that the diff housing has the same part numbers. This ALZ rear end could
explain some of the different experiences we are encountering on
different continents. To clarify the drawing comment, many of the sport
q pictures use ur-q pictures, so audi took some shortcuts here. 

And for Jouko's comments on never noticing anything odd in A4 testing,
doesn't your version of the A4 have EDL and if so, you wouldn't notice
the behavior others have described. With EDL, the distribution of torque
is also controlled by pulsing the brakes, which slows axle rotation at a
given end(or corner) of the car, which helps maintain the "current"
torque distribution through out negotiating a turn. This way it won't
change from RWD to FWD to RWD all in the same turn.

I am surprised that more people haven't felt the sensation of the
quattro hunt for traction. It is very subtle, but noticeable. I can feel
it on both my gen I ur-q and gen II torsen CD 200. It is most apparent
when accelerating from a stop in zero traction conditions, like using
big wide worn summer tires on glare ice. When getting the car moving,
you can sense torque moving around between the front and rear axles in
search for the end with the greatest traction.
-
Dave