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# Re: Understanding

```In a message dated 98-04-08 17:19:47 EDT, you write:

YES eric you are correct, my interpretation of awd system was wrong.  IT is
side to side only.  However, processing those signals front to rear is not a
rocket science exercise.  Nor one with a hardware change.
<< As I've said before, if your going to go that far, why not ditch the
> torsen all together?
GREAT IDEA.  You finally got my point.

>So you never want the rears going faster than the fronts, huh? Well,
>before EDL can react, the rears must at least begin to spin a _little_
>faster than the fronts. At that point, Tshift to the front has already
>happened. EDL applies the rear brakes, thereby grabbing some of
>that power to generate heat. No torque transfer, you say? In fact, I
>can see torque oscillations as EDL slows, then releases (then slows
>again, etc.) the rears through the turn.
Remember with slip angle, the rear tires CAN spin faster than the fronts, in
fact you can have them spinning and smoking, without the DRIVESHAFT spinning
faster than the front.  For that EDL could work.  I don't think you grasp the
slip angle issue.  This can work even as a release system.
>It seems that you are trying to take the scientific high road with
>your "physics" argument. Well, let's follow it through using the
>scientific method. You have documented an event, and come up
>with an hypothesis. In order for it to graduate to a theory, you
>have to come up with a repeatable experiment so that the rest of
>us can verify your results. How about a step-by-step recipe for
>spider stew?
Ah, the model.  Too many variables to predict it.  Please do help.  The
factors are cf, slip angle fronts, BR, slip angle rears, relative slip angle,
wheelbase, tires, suspension, Trg, throttle position.  I freely admit to not
being able to PREDICT it.  I can use physics to show what CAN happen.  WHEN?
Sure wish I could.  Can I make it happen in YOUR car.  Yup.  Do I know EXACTLY
how and when?  Nope, it's fine line between the torsen as your friend and your
'widow'.  Sorry.  Does that deny Tshift, nope.  Is that an event, yes.
Repeatable?  Sure.  Predictable.  NO.

> Others have tried to recreate the "bite" without success. You
>shrug it off as a "non event." Not a very scientific response. I
>have already suggested hooking up a laptop to the ABS sensors
>to see what each wheel was actually doing during the "bite." Not
>much interest in that one, I guess. It seems that you have lost a
>bit of objectivity in response to the (frequently unjustified)
>attacks of your findings. You ask people to argue the physics
>with you. I argue that you have some homework left to do before
>we can accept your hypothesis.
Tshift happens, and it CAN affect chassis dynamics.  Does it?  I argue yes,
you and/or others argues no.  I only need to present that it can.  And it
explains the chassis dynamics of WHAT HAPPENED in my event.  So there is
correlation.  A non event has no correlation to the physics, only to the
matrix of the yet to be determined model of non-events.

>The simple formulae do indeed show that Tshift happens. No
>argument there. Plugging in numbers to come up with values
> for the shift is monkey-work. It demonstrates nothing more than
>whether or not you have one of the flawed Pentiums. Proving
>that Tshift is the source of your "bite" is the real issue here.
Well it explains my event, in terms of chassis dynamics and actual experience.
Exactly what I'd expect actually based on the physics and the numbers.
Noneventers cant' explain my event at all.  I can explain nonevents easily.

Scott

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