Let's talk about quattro driving in the snow

[Brett Dikeman]

Scott, let me know if I say anything really stupid here :-)

Disclaimer- I'm not an expert(I'm not an instructor, either), you're
responsible for your own driving, blah blah blah yadda yadda.

At 5:08 PM -0800 12/3/02, Sean Ford wrote:
>This is my first winter with quattro. Just this morning, with fresh
>snow on the ground, the front
>slid straight and the car continued to move in a straight line.
>Obviously, this isn't the best
>situation when one is expecting to successfully complete a corner!

Actually, it's a lot better than the alternative(oversteer.)
Understeer is what happens under power, and it's usually easier to
correct in a FWD or quattro, because in both cases, your instinctive
reaction(get off the gas to 'slow down') is a good thing.


>I've driven both fwd and rwd cars in the snow. FWD will lose the
>front, but a quick pull on the
>emergency brake will swing the rear around.

Pull the handbrake, and now you've lost all FOUR wheels :-)


>Once I lose the front with quattro, what is the best way to rotate the car?

You shouldn't be thinking of 'rotating' the car(angle doesn't get you
around corners, GRIP does), you should be thinking about regaining
control(ie, get the car pointed the way it's travelling) and stopping
if necessary.

Two reasons:

a)if you DO hit something, you're hitting it in the worst possible
way, with the side of the car or at some angle other than head on.
Cars and restraint devices are designed for head-on collisions.  This
applies even if you're going to go into traffic; if you've got
understeer and you're heading into the oncoming lane for example, and
you decide to rotate the car by inducting oversteer, that places
about 4-5" of car between you and a car coming at you with a
differential of at least 40-50 mph...versus several feet of metal,
crumple zones, airbag, seatbelt, etc.

b)if you get the wheels gripping, you've at least got a prayer of
slowing the car, and every bit of speed you can bleed off is speed
your body, your car, and the other object don't have to deal with
later.  Sideways?  You're a passenger on a slip'n'slide.

   When Chris Miller crashed at Watkins Glen, he did the right thing-
he got the car going straight, and just whaled on the brakes, because
he knew he wouldn't make it.  The result was that right until he hit
the foam wall, his nice big porsche calipers were slowing the car and
his nice sticky tires were working 100%.  Between that and the foam,
he walked away without a scratch and the engine was fine save torn
mounts and cracked tbelt cover(body was a complete loss from the
mirrors forward, pretty much.)


>  I recall some advice warning against lifting off the throttle
>because the engine braking on the rear wheels could cause
>an unwanted spin.

The warning is for lifting mid-turn, near the limit of traction or if
you're in a slide. It causes a weight shift to the front of the car
OFF the back wheels, which will cause oversteer.


>  Though, if I don't lift off the throttle, the front will simply continue to
>push.

The correct behavior, for when you've got understeer, is your natural
reaction- to let off the gas pedal.  It transfers weight forward and
gives you more grip up front.

>Interesting from a dynamic, after-the-event, point of view. Frightening from a
>happening-right-friggin'-now point of view.

Come to a NEQ winter driver school.  Bring the missus, too.  You'll
learn a lot, and have a blast.  Heck, look what I learned just
picking cones :-)

Brett
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