quattro handling at the edge

[Matt Evans]

As Ti pointed out, this is situational and vehicle specific.

However, I have the following observations:
- don't buy any bridges from whomever told you to lift in an RWD car when
the rear starts to come around.  Guess what lifting does.  It unloads the
rear even more, reducing rear traction, meaning the rear is now sticking to
the road even less than it was when it was already sticking so poorly that
it could come around.  Congratulations, you've spun.  OTOH, LTO (lift
throttle oversteer) is fun if you are expecting it, or if the point is to
spin out :P

The safest advice I've got for you when the rear comes around in an RWD car
is to STEER through it and keep the throttle constant, or SLIGHTLY add
throttle to get some more weight on the rears.  The key here is STEERING
through the slide though.. As if the rear moves AT ALL your steering is not
pointed where it used to be.  Just associate the two naturally - "rear
moves, so does the steering wheel"

Disclaimer - my summer car is a RWD 1988 BMW M5 :)

- Now, onto quattro at the limit -
Honestly, this depends on a bunch of things, tires being the biggest part of
it, but also the weight distribution of your vehicle, your alignment, and
your bar settings (and lots of other stuff even).  Also, "at the limit" can
have a few different contexts.  There is such a thing as car that will
understeer on turn in and oversteer under power, or understeer at speed but
not at lower speeds.

In my 88 90Q, with blown rear shocks and bushings everywhere, I found the
handling to be very neutral if not surprisingly biased to oversteering.  In
the snow I've found that mid way through most turns I can get the rear to
come around without significant mucking around, so the car seems to be
moderately biased for oversteer.  Its very easy to get the rear loose and
keep it loose in this car; you can do some wonderful figure 8 drifts just by
squeezing on and off the gas pedal (with wheel input, naturally).  If you
want to turn 90 degrees INSTANTLY, left foot brake as you're starting your
directional transition.. Just a quick stab on the brakes.

This is also possible on pavement with low grip tires.. Even with the NG
motor.  People following me on the street tell me that I lift my inside rear
wheel on turns, so, assuming that's not just a function of blown shocks,
that's definitely a FWD characteristic.

The best advice I've seen is to go find a skid pad (snowy parking lot will
do) and just try different stuff.  You'll need to try a variety of speeds
and surfaces to really know, but ultimately its irrelevant - nearly any car
can be made to understeer or oversteer, so you need to anticipate and
correct for both :)

Matt
88 BMW M5 (tail wagger in the dry)
88 Audi 90Q (tail wagger in the snow)
00 Passat Wagon (no tail wagging due to "dynamic stability control module"
installed in passenger seat)




> Date: Mon, 26 Jul 2004 10:56:09 -0500 (CDT)
> From: lws at o-o.yi.org
> Subject: quattro handling dynamics at the edge
> To: quattro at audifans.com
> 
> Hi, I have a question about driving a Quattro when you start to lose
> traction.
> 
> The rule of thumb for RWD is to back off the throttle when 
> the rear comes
> around, and with FWD the rule is to hold steady as long as 
> you still can
> feel traction through the steering wheel.  What do you do 
> with quattro,
> when the balance keeps dynamically shifting back and forth?  
> Do you get
> any warning that you're about to totally lose traction before all hell
> breaks loose?
> Or does the car just handle fine, right up until the moment 
> it doesn't?