quattro: The Next Generation

["Lawson, Dave" <dlawson@ball.com>]

After seeing the new TT coupe zipping around Boulder, Colorado, I will say 
that Audi is finally building a car which I would be interested in buying
new.
They look better in real life than the photos and they are slick looking. I
finally
got to spend a bit of time looking over the silver one which Frank A. saw a 
few weeks back. It looks great, the lines are good, big 17 in wheels, just a
nice all round car, which to me, is as striking as the first time I saw an
ur-quattro in real life. My wife likes the looks and even likes the pictures
of the spyder version better.

To learn more I started reading up on the car and particularly the "new"
quattro system. Dave E. sent a post on Sep 9 or so detailing the Haldex
LSC (limited slip coupling) which is used as a center diff. I dug up some
info on the new golf 4motion system, since this is basically the same
system. And then yesterday the new issue of Racecar Engineering (V8N8)
shows up in the mailbox with an article about the Haldex LSC being used as 
the center diff of choice in the euro rallycross series.

These sources talk about how the torque split can vary from 95/5% to 
5/95% or thereabouts, but I can't quite figure out how this device is 
capable of it. For the TT/S3/4motion system, there appears to be 1 
input and 1 output shaft, with the LSC based center diff mounted to 
the rear differential. In this configuration with the clutch pack fully 
locked, the center driveshaft is locked to rotate with the rear axle. What 
appears to be missing, is the documentation/discussion about the 
transmission and front differential and how they transmit torque to 
the center driveshaft in this "new" quattro system. Particularly how you 
would transmit all (or 95%) of the engine torque to the center diff LSC 
mounted at the rear diff. Has anyone got any information about the front 
gearbox/differential? All the cutaway drawings I have seen don't show 
the engine/tranny configuration.

This "new" quattro system sounds interesting, since it is partially computer

controlled and is a device on the CAN bus. The rallycross teams change 
torque split/chassis behavior programs by downloading from a laptop. I
have already got those nasty ideas in my head, like what kind of car do
I want my TT to drive like today...
-
Dave Lawson