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Re: Dave, you're still confused

In a message dated 98-04-22 19:17:20 EDT, you write:

> err, no...in the low cf situation, the locker hunts from 100-0 and 0-100. 
> thats a greater tshift than the torsen.  orin made this point (which i
 >appreciated), that, (eg. front axle on ice) due to the 0 torque *reaction*
> low cf in these conditions, the locker *can't* send torque to that axle
> (because of the 0% torque reaction from the wheels on ice).  the result is
> torque to the axle, 100% (effectively) to the other.  spider bite.  although
> this makes sense to me, i'm still not clear on this though.  is the panel
 >paying attention?
NO, this is not correct.  Orin made the point that this can occur when the
wheels are on different cf's.  For KISS, and where the bite occurs, is when
the wheels are on the same cf.  You don't want to go here dave.  Let's put all
four wheels on ice or snow, or gravel.  That is the real world of a turn.
Torsen or locker, in a turn, if you have anything else, NEITHER device will
give you much advantage in chassis control if cf varies wheel to wheel.  You
don't understand 4 wheels on the same cf yet, please don't jump ahead to the
next set of variables, the supercray is already overloaded.
 >either way, the locker either has a tshift max of 50% of torque, or 100% of
> torque in low cf conditions.  thats a spider bite by your definition.  the
> torsen is either better or worse, depending upon the paragraph above.
> way, not a hill of beans.
NO Dave.  Get the 4 wheels on the same cf.  You HAVE to use this scenario.
You don't understand your own argument.  I don't want to address it, because
you don't grasp the same cf yet.  Once you do, we can take a look at the
varying cf scenarios.  
> in high cf conditions?  now thats a different story...
No again, dave.  High cf conditions?  That makes me think that now you are
assuming 4 wheels with the same cf.  CF is a constant to the 4 wheels.  You
are making this too complicated for your own argument.
> central to this is that a locker is not a torque distribution device, it is
> [driveshaft] rotation *equalising* device.  it will ensure that both shafts
> rotate *at the same speed*.  if one shaft [wants to] speed up (no grip), the
> other will [effectively] brake it, but the vast majority of the *torque*
> go to the axle with grip.  so torque will swing front to rear and back
> while the dirveshafts are spinning *at the same speed*.  this is my
> understanding of the physics of the locker.  panel?
DAVE, SAME CF, THIS IS NOT CORRECT.  Think of this.  If you are driving in a
straight line, rears on pavement, fronts on ice.  Torque at the rear.  For
what lenth of time?  Exactly 99inches for your Urq.  Then the cf is constant.
You don't want this argument sir.
> nit 2:
 >when i said 70% torque, i was assuming there was 0% torque reaction from the
> other axle.  net is 70%.
NO.  You said Tshift Max is 70%.  That is incorrect.  Tshift is 56%.  You
can't assume 0% torque reaction from the other axle with a 3:1 BR can you?
You confuse the panel with this "net" stuff.  We are talking about what
potentially bites, or upsets the chassis dynamics in a turn.  That is Tshift.
NOT net shift, or net torque to any axle.  It's the amount that transfers
between them that causes the bite.  A major nit.
> nit 3:
> by the same definition, the locker also hunts (loses traction on one axle,
> torque reaction, regains traction and 50% torque reaction.  to use your own
> words:
> "A [locker] that "hunts" in a straight line will also hunt in a turn.
> the difference, the dumb switch is only more confused about the 'traction'
> inputs in a turn, cuz there's more of em."
No Dave.  An open diff will hunt, a locker will resist spin up of either axle
(again you need to constant cf here).  Why?  Because they are absolutely
locked together, and no TRANSFER of torque is taking place.  An open diff will
transfer 0-100-100-0, a torsen 22-78-78-22, a locker 0.  .  A locker doesn't
hunt in a straight line in constant cf.  Sorry, but you have this wrong too
sir.  Dave, you are trying to explain things to a panel, that you don't
understand yourself.  Rather confusing actually.

Scott Justusson