Arachnophobia (long)

[QSHIPQ@aol.com]

I spoke with Jeff G. (Audidudi) yesterday and Dave L today on the land line,
and it appears there is a lot of interest, and plenty of been there done that
in terms of experiencing Torsen behavior.  I find most interesting, Dave E.'s
comments regarding the Torsen and predictability.  We can go thru all the
theory, but until that spider takes a strike at you, there is a very pro-
torsen feel from those who haven't crossed that line.  Personally, I've seen
the really ugly side of Torsen, not just on occasion, but many times.  Some
others have too, including Jeff.  I make no claims on my driving prowess,
however, anyone that has sat beside me (as driver or passenger), knows my q-
tango moves are far from delicate and without full understanding of quattro
chassis dynamics.  Where I and many others here on the list have been, should
indicate that there is something up with those Torsen cars.  Guilt by
association:  Why don't/didn't the factory cars use them in racing?

What do those of us that have gotten bitten do?  Well, in the case of Jeff and
I, it intrigued us, to the point of really nerding into the how and why of
center spider gears.  What did both of us find out?  Well, for one, audi is
the only company (albeit in a small handful of awd producers) that took the
torsen route for center diffs.  And although Audi AG took that route as of 88,
they never used that same torsen in any of their factory racing efforts.  What
did they know that we don't?

Audi knew that few would venture to the limits of Torsen, that's what.  Dave
E. with his two high HP cars has found that the limit is high, so high that he
hasn't been bitten.  I don't doubt that as so.  I might also add:  Yet.
Granted we are talking at the edge of the envelope, but a bite is just that.
Me, I want to explore this phenomenon in terms of what can be done to avoid
that nasty.  Why?  Because the number that haven't been bitten exponentially
exceeds those that have.  I personally find it really hard to believe, but
reality is, I enjoy pushing the envelope to explore the limits of a given
chassis all the time.   Then try to correct found flaws.  Many efforts sit on
my and others' toys from this concept, some worked, some didn't.

The smoothness issue brought up doesn't really do much for this discussion.
There is a line beyond which the torsen will do what it wants, dispite your
efforts, it does by definition.  You have no control over what the torsen
does, it doesn't care or know what you are doing or why.  It senses a
differerntial driveshaft speed, that's all, a variable, at the limit, a big
one.  If you take the "set and forget" driving technique (you steer once to
apex and throttle the rest, unwinding the wheel only) the Torsen behavior can
upset that without being anything but really smooth.  Why?  Because a Torsen
can make you steer even with your throttle input.  Driving a quattro fast is
being smooth by definition.  Someone really needs to explain why there is this
grand disparity between audis commitment to Torsen for the street, but NONE at
the track or in Rally.  Why, Why? Why?  Could it be there is a better way?  A
faster way, being just as smooth?  I submit exactly that.    

Right now, more questions than answers, but a few of us want to really figure
this beast out, or at least explain how and why one can't.  Nothing I've
experienced to date in a chassis, is as disconcerting to me than a hunting
center Torsen.  Period.  I make only that argument from many btdt.  And I only
make it after driving all audi chassis with them, save only Dave E.'s RS2.
Certainly after really analyzing the Torsen properties in the last year, Jeff
has come away with some interesting conclusions, running very parralel with
mine.  Whether one can carve a turn or not with it, really is irrelevent to
what we are trying to explore.  I know the hunt can be felt, I've had it
driving leasurely down a snow covered road.  Change that into a more
performance arena, the hunt gets more upsetting.  Stepping on the gas seems to
be the easiest answer, however, the practicality of that has risk associated
with it, and statistics with those risks.  Even a look at the number center
diffs of the Qclub quattros that have tasted Armco vs non tosen cars that have
done the same, might just indicate that handling a torsen is not an easy task.

So, I make no bones about the fact this Torsen spider exists.  If we look hard
enough at the phenomenon, maybe some correction can be made to it's darker
side.  That's what I'm after, me thinks Jeff too.  Happy to share it with the
List, in hopes that maybe the ones that get bitten don't tithe the sacrificial
fenders of their q-unit.  Overdramatic?  I suppose one could say that.  I can
also share, with anyone that thinks it's not a lurking risk at all, a ride
that might prove enlightening.  Torsens should be given a lot of respect for
what they are, as well as what they are exactly not:  User friendly at the
limit.  To date:  A "duh" from those bitten, a "hunh" from those not.

BTW, you have a Center Torsen if you have a audi awd car later than 1988.
Easier yet, if you don't have a center diff knob.  1988 90q was the first.  44
chassis cars fell to torsen in 89 (including both early and late models)  You
have a locking rear (disabled at 15mph) on your Torsen center thru 1992.  1992
S4 cars (these are stateside comments folks), have the rear locker, 1993
forward, all S cars have torsen rear diffs, all 20vt cars have Torsen Centers.
ALL v8 cars have Torsen rears, all 5 spd v8's torsen centers, some automatics
have electro magnetic plate centers.  1988> locking rear diffs that are self-
disabling, can be defeated to operate at all times (per Dave Lawson post -
archives).  I'm sure Audi has many reasons why that diff is self defeating,
none of them interest those really looking for a performance gain.  And a
relatively simple mod to make.

Really happy to go offline again with a few that are really interested, btdt.
However, there are more Torsen awd quattros on the road now than non, so I
believe these discussions to be most most relevent.  And IMO, some btdt has
put this list much further ahead than when this surfaced last, about 1.5years
ago.  So progress made, but not corrections.  This Torsen center diff
technology is 10years old for audi, but not proven in their own racing
efforts, but a wholly committed technology in street car marketing.
Mainstream sells cars, that 7/10ths world....  Bummer. :)

There are those who will never cross the line.  I firmly believe that.  I also
firmly believe that if you do, you will find a very uncooperative force
waiting to punish you for pressing too far.  Those that want to convince
themselves it isn't there, need only a ride by one in the know.

May the force be with you, all the way thru the apex...
My .02

Scott Justusson
QSHIPQ@aol.com
'87 5ktqwRS2
'86 5ktqw
'84 Urq