RE: Torsen post for Gary

["Eric Renneisen" <renneie@hlthsrc.com>]

QSHIPQ writes:
> Eric, understand that the torsen should have axle slip built 
> into the design,  Stans point (or how could you take a turn 
> in a rear diff rwd car?)  

Yes, I understand that completely. What exactly in my post led 
you to believe that I _don't_ understand this?

> We could see that in a 80q the radius is "significant" to 
> torsen allocation and is measureable at 40m and 15m at a given 
> rate of accel and other given conditions

How was this measured? Were the front and rear driveshafts 
spinning at different rates? If so, according to Stan, you're 
at the BR, period. Hmmm... maybe you're saying that some of the 
torque is being used to compensate for the slip angle 
differences between front and rear, and the split measurements 
quoted in the SAE paper are what's left over? Or maybe Stan got 
it wrong and the torque distribution is directly related to how 
fast one driveshaft is spinning relative to the other?

> Again, you have traction and slip angle as torsen inputs.

Sure, but as you've stated countless times, it can't tell the 
difference between the two. Both are treated as simply increased 
or decreased resistance to rotation. From what I understand, in 
order for the Torsen to begin differentiation, the resistance to 
rotation of one driveshaft must be sufficiently greater than the 
other, then the Torsen is _forced_ to differentiate (it won't do 
it _until_ the bias ratio is reached, according to Stan), and 
the whole TORqueSENsing aspect of the device is found in its 
resistance to differentiation.

My understanding is that up until the point where the Torsen 
differentiates it is behaving _exactly_ like the locker. It has 
to. The driveshafts are spinning at the same speed, and the 
gears inside the Torsen are not spinning. Things don't get 
interesting until you force it to differentiate by turning.
(you'd say, "darn turns")

My question is very basic, really. Stan says that it 
differentiates at the BR, 885140 seems to say that the torque 
split is variable when differentiating. You say they're both 
right. How's that? I don't care about the inputs, the Torsen 
doesn't care or "know" where they came from (slip vs traction), 
I'm just concerned with the device's outputs.

Eric Renneisen
'90 CQ 20V  -  my 'racing-iron'  ;^)
Chattanooga, TN