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Come play with us Davey

Dave E. writes:
>reading scott's response makes me appreciate afresh the pointlessness of
>this exercise.  i could respond to every point with a rebuttal, but
>obviously to no avail.  i guess i'd thought that posting the zexel paper
>would help lift the fog some, but it hasn't.  so be it.

The Zexel paper hasn't created fog, nor has it refuted my, Jeff or Chocholek's
proffers of the limits of the device.  Just as difficult to find as Stan's
paper, in that what isn't said is as important as what is.  Misunderstanding
what is written creates the fog.  How many times can you see 'spin' in this
paper?  The best yet, IMO.  And I totally understand what is written and what
is not.

>scott's response and obdurate refusal to understand any other view than
>his own experience of a single audi torsen chassis, really makes the
>whole exercise doubly futile.  i have never questioned that the torsen
>is a dumb device, 

I believe your last post contradicts this very statement.  Obdurate?  Well yes
I have little sympathy OR empathy for a dumb gear jamming fricitional device,
that anticipates a reality that may not exist, furthering a propensity to hit
the perverbial F1 key - so assigned as defined in the Zexel paper.
>just as any other awd technology is (vc, or locker, or
>clutch system).  all stupid.  that is not the issue.  the issue is "is
>the torsen unsafe?", "does it bite?".  the paper shows that the torsen
>centre works considerably better than the locked or open centre up to
>the limits of adhesion.  because it seeks to maximise longitudinal slip
>(i.e.. torque reaction). so experienced.  so written about in many road
>tests.  scott disagrees.

Damn those turns...

 > he throws "u"s and "o"s around to attempt to
>show what this fiendish device is *really* doing.  unbeknown to us mere

Gee Dave, I thought it was you that brought up "chassis dynamics".  Maybe we
need to get that chassis dynamics thesaurus the Zexel boys used to find some
other words for U and O.

>or the road test drivers who *all* mention the improved feel of
>the torsen ur-q, decreased understeer, and better throttle steerability
>over the generation 1 car.  so posted.  i guess we're all being fooled.
>back to playschool....

Just a non event, no more.  A torsen that *can* be fooled, obdurately does.
"Feel" has a way of changing when engine torque and cf changes.  So stated in
the Zexel paper.

>for scott, a torsen is a torsen is a torsen and, because of issues with
>the chassis he's driven, all chassis *must* have a problem.  a clear
>victory for the scientific [sic] method. 
Nope haven't driven ALL chassis, only the device, and so understood.  Don't
need to drive all iterations, given the dumb gear jamming frictional device.
It's not magical in one chassis and not in another.  It's not smart enough to
know the difference.

> i say, and the paper agrees,
>that the chassis is a major component of all this, and could explain the
>behaviour experienced by some.  "bite" caused by hand-brake application
>on wet on-ramps notwithstanding.

...  And the paper sums with a change in engine and cf changes the paper.
Major component.  Yup, chassis is, so is the engine and cf.  And the paper
doesn't agree, it states it as so, 3 times in the part of the paper you
posted.  So chassis dynamics is a PART of torsen behavior.   Wonder how that
changes as you change engine torque and cf?  Or relative slip.

>so, i'll go back to driving my torsen-equipped chassis fast around
>corners, finding as i have done, that they exhibit wonderful throttle
>sensitivity at the limit of adhesion, wet or dry.  i'll take my torsen
>ur-q, as i did last week, to a subaru grass track day, and find, again,
>that even in these conditions, against "modern" cars with dumb vc's, the
>ur-quattro is fantastic.  bite?  bollocks.
That Zexel paper makes some better drivers.  Unfortunately, the dumb device is
still dumb, and dumber than many of the others.  Smart drivers don't make dumb
devices smarter, in fact we can look a the above...

Hey davey, if the 44 chassis bite (your claim) but not Urq's, how 'bout
experiencing one so that you know what it is.  Then we have a better baseline
of understanding.  Kinda like talking about sex to a virgin...  (sorry
playskool analogy/pun).   A whole bunch of us dumb non-engineer types can help
you here.

>i guess when playshool is over, you get a chance to play with your toys.
>i'll have the full zexel paper ready by the end of the week....

The full Monty?  Super.  Though I think what you posted is plenty.  Just needs
some studying, just like Chocholeks paper of 1988.  Neither contradicts me,
Jeff or Chocholek.  Given the device, and the experiences, one could say that
some play with their toys more than others (insert palm-pilot joke here:).
Steamboat is last week of January Dave.  Comon' out, plenty of torsen
experiences await you, pick any torsen car for me to drive.  You might find
out why it's so hard to find Torsen's in racing venues.

All due respect to your grass stains.

Scott Justusson
Playskool idjiot 1988