Audi in London

[Dave]

you can't take the technology is isolation from the chassis.  for example,
my allroad is stunning on a gravel road (caveat: esp off) - the krauts don't
have gravel roads, don't understand gravel roads, and don't engineer for
gravel roads) - much better than the rs6.  complete reverse over a nice
sealed road.  same transmission technology, different chassis tech.

also the torsen operates like a limited slip diff.  like an lsd it can only
take the traction available from the low traction side, and multiply that to
the higher traction side (e.g. 0 x 2.5 = bugger all).  hence the focus on
edl to force torque back into the system by braking a recalcitrant wheel.  a
locking diff doesn't know and doesn't care - and so is better (on it's own)
in low-traction conditions.

the later, recent t-3 models operate on a different principle in that they
incorporate a planetary gear set to ensure a constant asymmetric torque
distribution during normal conditions, until traction conditions force the
split to vary.  whereas the t-2 torsen has a normal operating torque split
that effectively mirrors the weight distribution of the vehicle, (60:40 f:r
usually), the t-3 forces a 40:60 f:r.  this can be made to make quite a
difference to how the car can be made to handle - hence the rs4...

$0.02

dave
'03 rs6
'04 allroad tdi


On 4/02/09 8:48 AM, "quattro-request at audifans.com"
<quattro-request at audifans.com> wrote:

> Date: Tue, 3 Feb 2009 14:06:21 -0500
> From: "Bares, Vittorio" <Vittorio.Bares at nuance.com>
> Subject: RE: Audi in London

> Torsen and locking diffs are both compromises and have their place given
> different circumstances.
> 
>  
> 
> Locking diffs absolutely rock in straight-line braking and acceleration.
> Torsen kicks locking diff butt, in the actual corner where power can be
> better distributed while actually allowing differential wheel speed on
> the inside and the outside wheels.
> 
>  
> 
> Personally, I consider both configurations 'real' quattro - Haldex
> however is like using alcohol to prevent infection before a lethal
> injection to a condemned man .
> 
>  
> 
> Vittorio -