Whoa, horsie

[QSHIPQ <QSHIPQ@aol.com>]

Hey guys!
Torsens are great absolute traction devices.  That is all they are.  For most
of the buying and driving public, they are just fine, thank you.  That
includes those of you who brake and turn without a racing background.  When
Trg is low, maximum Bias Ratio of a torsen don't mean beans.  That includes
braking, clutch in, coasting, and light throttle.  Driving normally.

Torsens are ONLY absolute traction devices.  That is to say, when turning,
they don't know the car is turning.  Why?  Cuz they are dumb.  Again, for
normal driving, dumb don't mean beans.  Where they start to mound is when you
go to a couple driving schools, and learn the intimacies of "the line"
"oversteer" "understeer" "slip angle" and "relative slip angles".  Then you
understand what Jeff and I are speaking of.  We are both convinced that a true
racing line upsets center torsen audi chassis dynamics while turning.
Correcting for this chassis dynamics is correcting the bite to some extent.
The problem is, that "correcting the bite" with steering, braking, or massive
throttle shifts, means you are slower around the 'line' than you could be.

A bad thing?  For most drivers no.  However, there is that first snowfall, or
that first time you play 'quattro' in the rain, that some nasty torsen
behavior can bite you right in the wallet.  Why?  Cuz, when a torsen steps out
in low cf (or high cf for that matter), the predictibility of that set of
spider gears is out the window.  You can't predict a dumb device that can be
fooled by slip and relative slip in a turn, especially when low cf raises
significance of the variables.  Still, all these compromises add up to a
quattro, that has a high level of traction and security under the right
parameters.

What several have discovered, is a wee bit of the dark side of a fooled "dumb
gear-jamming frictional device".  A major revelation?  Naw, it's been there
all the time, Chocholek just confirmed the dumbness of the device.  It's NOT
smart, it's NOT always predictable, and it's NOT anything but an absolute
traction device, and it CAN affect chassis dynamics in a turn.  So stated in
the paper on Jeff's page, rehashed by Jeff and I infinitely, and confirmed by
Chocholek.  So what?

Hey, a choice by audi to "improve" the absolute traction equation, at the
expense of a few compromises in turning.  Customers are happy they have awd,
the abs works all the time, and they don't have to lock and unlock dem
switches.  Any different a decision than the self defeating rear locker.
Prolly not.  Active awd and no ABS takes thinking by the one behind the wheel,
a torsen doesn't.  Those compromises seem small to Audi AG and most owners.

What seems somewhat puzzling to me, is the fanatical commitment to Torsen,
given it's limited racing use, and a simpler dumber device evolving to bear
solid fruit, the VC, with all it's inherent chassis characters.  A torsen in a
straight line can win an absolute traction comparo.  But not so in a turn.  Is
absolute traction THE answer?  Ignoring chassis dynamics in a turn, you could
argue yes.  Seems Audi took this line, all alone in the industry, still is,
and this chassis dynamics while turning, by Chocholek's own B-L account, as
well as audis own racing efforts, shows this to be a known entity with plenty
of compromises.  Many inside and outside audi consider unacceptable.

Defend it?  Why?  It is dumb, it needs no defense, it's just a switch.
Defending the choice by audi to use it?  Why?  It is what it is, no more, a
dumb device can't be smart.  The center locker was used extensively in audi
racing (documented everywhere), not so the center torsen (we can barely point
to where it was used in racing, it's that obscure, and even audi claims
Torsens amongst many in race spec sheets).  So audi chose to make the
compromises for absolute traction.  A decision that many (this is the qlist)
want to defend.  And a few of us challenge, cuz we've seen the dark side, many
a time.  And one racers don't choose, only agree to use on occasion (which
occasion was that?).

Now that the horse says that a torsen can be fooled, where do we go from here?
That means, by definition, there is a set of variables in every audi chassis
that can elicit bite phenomenon (U-O-U) in a turn.  Jeff is committed to the
fix.  I'm not that optimistic.  I find the simpler answer to be stick with the
lockers for real quattro fun.  Happy to go spider hunting with anyone that
claims the fix.  That's a lot of variables...

Ah, yes, well, enough already.  Plenty of heat still in the butane:).  And
here I thought that when Stan spoke, I'd just get a gold star, and rest my
keyboard....  Yea, right, hey pal, this IS the quattro list.

:)

Scott Justusson