RE: Torsen + EDL

[David Eaton <david.eaton@computerland.co.nz>]

yes eric, this is a major source of confusion...

scott continues to insist that he would see t-shift(max)
[=t(max)-t(min)] while the torsen is conrnering which beggers belief.
only in radical cornering - where traction is lost to one [virtual] axle
will we see this.  The case scott mentions occurs with the car spinning
through a corner with the rear axle not moving the car forward (!!), and
the fronts pointing through the turn, which is pretty extreme; i mean
you'd better practice this manouever at your local track...

part part and parcel of scotts arguments is that *rotational*
differences are what the torsen senses.  the gleason paper is not clear
on this.  heck the sucker is called torsen=torque sensing differential.
the paper implies that the invex gears are useful in allowing
differentialional between the driveshafts to be controlled *before* slip
occurs.  this can only happen is it is using torque reaction to control
differentiation, rather than simply rotational speed (like a normal
diff).

as they say, just the physics folks...

i agree with you about edl.  scott misunderstands how this works.  it is
quite clear from the description of it that it works *across* the open
diffs front and rear, and not between the drievshafts.  it will be a
significant advantage when one wheel starts to spin up.  but it is
simply the usual "traction control": technology used to make rwd cars
handle the slippry stuff adequately. scott also said that it disables at
40mph.  it disables at 80km/hr or 50mph...

dave
'95 rs2
'90 ur-q


>-----Original Message-----
>
>Date: Wed, 04 Mar 1998 10:46:18 -0500
>From: "Eric Renneisen" <renneie@hlthsrc.com>
>
>>By the same definition of a torsen center, as soon asyou turn, slip 
>>angle to the torsen becomes a variable.  INTERPRETED as a 
>>traction.  That's the problem.  4 Wheel EDL doesn't change that.  
>
>Maybe not, but 2 wheel EDL will affect which wheel on the front 
>gets the torque and which one on the back gets torque. By effectively 
>locking the front and/or rear diffs when spin-up occurs, EDL 
>definitely changes how the TORSEN reacts in your "bite" scenario. I 
>realize you wanted to hold off on the EDL discussion until the gen II 
>was sorted out, so we don't have to go any further into this. I'd still 
>like to know what Boris does when the rear diff is locked on the 
>gen II, though.
>
>BTW, as for the TORSEN extrapolating traction from driveshaft 
>speed, I'm not convinced. The Gleason tech paper seems to imply 
>that it's reacting to frictional resistance rather than speed 
>differences. I could be wrong, though. Maybe one of our MEs 
>should have a chat with them?
>
>Eric Renneisen
>'90 CQ 20V  -  my 'racing-iron'  ;^)
>Chattanooga, TN
>