Re: Torsen post for Gary

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

> Stan's paper is for rwd and fwd applications arguing traction, 

That's not my impression at all. I don't think Stan's paper 
concentrates on _any_ implementation F, C, or R, until you get 
to section 5 and 6. It's mostly just describing the operation 
and internals of the device, and that's where my questions are 
coming from. I don't care about where the inputs are coming from 
or where the outputs are going. I'm just trying to understand 
the device.

> Look at it this way Eric, Stan says that differentiation means 
> torque split is maximum  BR in a single axle.  What this means 
> is that indeed torsen slip is figured into the turning radius 
> of the car (your point).  

Was that my point? I'm glad you told me, because I thought it 
was something completely different!  :^)  Actually, I don't 
really have a point, just questions.

> Now, Relative slip should be figured ... so that each audi 
> torsen car can turn without changing torque allocation.  
> That's just not the case, 885140, or just turn your wheel to 
> full lock and accelerate.  

What I'm saying is that according to Stan you simply _can't_ 
"turn without changing torque allocation." I don't know if this 
supports or contradicts your theory, and frankly, I don't care.
I'm searching for truth, not victory.

> It should be noted that even if you can show an rwd or fwd 
> axle that does allocate torque based on slip angle 
> differences in a single axle (BR max by turning radius), you 
> need to go to the "next" step, what is the resultant chassis 
> behavior.  

No, I won't take any "next" step until I'm confident that I 
understand the device. I think I'm close, but I'm stumped by 
apparently conflicting information. I haven't yet seen 
anything that resolves the discrepancy.

> The difference between a locker and a torsen, is that a 
> torsen can allocate torque output to the rear, the locker 
> can't.  

Really? Tell that to Zain Horning who's broken front 
driveshaft/CV causes his 4KQ not to move unless the center is 
locked...
I believe that there are two main differences between the Torsen 
and the locker (locked diff):
1. The Tosen allows differentiation
2. The Torsen can only distribute torque up to the BR, the 
   locker can go 100:0 or 0:100

> Eric, all this information is available in 885140.  

OK, you've now got hard copy, right? I'll make the same request 
of you that you made of Dave... post it, please. The worst that 
could happen is that the SAE would demand that you take it down.

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