RE: open diffs at the limit.

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

no dave,  we've lost traction at [either] axle.  same scenario as scott
proposed with the torsen....

agree with your conclusions about the open centre diff, but you 'lose'
an axle with the centre diff locked and you might be sending 50% of
torque that way, but none is getting to the ground.  the torsen is
sending (wasting) 30% of it's torque, while the generation 1 setup is
wasting 50%.  win for the torsen.

btw, with regard to your point about no-one else using torsen, there are
only a few manufacturers doing awd cars.  what i've been told is that
the torsen is *significantly* more expensive than a vc, which makes the
vc (even with the abs compromises that involves) more attractive.  as
far as i understand it, the vc is also easier to engineer with a large
static torque split (i think that the volvo uses a 95:5 f:r ratio for
example).

dave
'95 rs2
'90 ur-q


>-----Original Message-----
>
>Date: Tue, 3 Mar 1998 14:53:40 -0700
>From: "Lawson, Dave" <dlawson@ball.com>
>Subject: RE: Dave, Phil et. al. - some thoughts
>
>>
>"Trg = 300lb/ft car 75/25/25/75.  KISS, look at what that means in
>Tshift.
>
>T1 = 225lb/ft
>T2 = 75 lb/ft
>OR, anywhere in between.
>T1 = 75 lb/ft
>
>T2 = 225 lb/ft
>Tshift MAX = 150lb/ft"
>
>ok, here we go locked centre generation 1 quattro in the same scenario:-
>
>t1=0
>t2=150lb/ft
>tshift max = 150lb/ft
>
>or,
>t1=150lb/ft
>t2=0lb/ft
>tshift max = 150lb/ft
>>
>
>Dave, for the locked center, the split is 50/50, so given the 300 input,
>the numbers would be 
>
>t1=150lb/ft
>t2=150lb/ft
>tshift max = 0lb/ft
>
>or,
>t1=150lb/ft
>t2=150lb/ft
>tshift max = 0lb/ft
>
>
>