Re: torsen silver stake (part xxxiv)

[Dave Eaton <dave.eaton@minedu.govt.nz>]

man, i love the condescending note in the recent posts.  clearly we all have
too much time on our hands...

the statement is, and has *not* been retracted, the "torsen spider bite happens
at 7/10th's cornering on dry road".

scott, in his superior wisdom, has stated that this behaviour is tracable to
the torsen diff sitting in the cars.  and, because he understands the physics
of the torsen, and that a torsen is a torsen is a torsen, then, *by
definition*, it happens in all audi's with torsens.  others have documented
experiences of this behaviour in their cars.

data points:

1) all the experiences have been in the usa, and in type 44 (vast majority 5??)
and 89 cars (how many?).

2) there have been no experiences of spider bite in the ur-q, and other
european cars.  we've even had juoko going to ice school in a4's and reporting
no problems.  i have undertaken skid training in a4's and a6's (including skid
training with *both* wheels on the same side of the car exposed to low cf
surfaces).  i have watched walter rohrl from the passenger seat as he took my
ur-q around a circuit.  guess it wasn't at 7/10ths.  no bite, no mention of
bite from the instructors, no experience of bite from any of the
drivers/instructors.

3) it is now beyond dispute that audi rallyed and raced with the torsen centre.
despite that, according to scott, a torsen is a torsen is a torsen.

4) clearly an event has happened to drivers at various times.  this is not in
dispute.  what is in dispute is the cause of the event, and the solution to it.
 much like the bmw driver complaining to the dealer because of an oversteering
moment caused by worn tyres, wrong throttle imputs and bad conditons, and then
blaming the car, more data has to be gathered to fully understand this event.

5) a number of people (myself included) have tried very hard to reproduce this
problem.  i have tried to deliberately unsettle my cars areound wet
round-abouts, left foot braking, sudden throttle inputs, oversteer on entry,
understeer on entry.  all at the dead of night, all in the wet, all at high
speed.  phil has done simmilar things on this ur-q.  i have undertaken a number
(3) of driver training courses, and at the most recent one, came 2nd out of 30
people in the timed laps, beating 2 national saloon champions (and lost to 1). 
i am a reasonable driver, who understands my cars and their behaviour at speed
and in extremis.

6) it has been shown that audi used different model torsens in my two cars, the
ur-q and the rs2, with significant differences apparent from the fiche
diagrams.  despite this, neither of my cars displays any different
charactersitics when cornering at speed.

7) i have *never* been surprised by my car when cornering.  with oversteer,
opposite lock and throttle will correct it.  with understeer, throttle lift
and/or lf braking will correct it.  i have (eg. this morning) had wheel lift in
my cars on twisty roads, without any surprises.  i can corner with 4-wheel
drifts, or screw up a corner completely without the car ever giving me a moment
of concern, other than what i shoud expect :-)

8) clearly the torsen depends upon the torque reaction from the wheels for it's
inputs.  the state of the tyres, the traction conditions, the quality of the
suspension, the state of the dampers, all pay a significant role in this
equation.  let-alone the design of the chassis.  none of the argument has taken
any account of these factors.  in fact the argument has been that, because of
the physics [sic] of the torsen, *none* of these things matter.  this is
completely wrong, obviously.

7) no one who proposes that this is a fundamental propoerty of the torsen, has
been able to describe to me that things i should do to reproduce this event,
despite the mantra that it occurs at 7/10th's on dry tarmac.  i am still
waiting for this, but trying my best despite the lack of information...

i resent the implications about me of a number of the contributors to this
thread, but hey, we're all big boys, and ignore this shit.

what i'd like to see now is for each person who has experienced this event to
provide documentation of the event, the conditions, the drivers actions, the
vehicles reactions, the type and repair of the vehicle.

lets get some data here.

7/10th's on dry tarmac corners?  sheesh...

dave
'95 rs2
'90 ur-q