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Re: when to shut off ABS??

In a message dated 96-12-09 12:41:47 EST, you write:
Bob writes>>>
ABS off on ice>>>
Then Eric writes:
<< For 99.9% of the general public this is a BAD call....  They just don't 
 have a brake foot that is sensitve enough to what's going on at the 
 wheels, and to top it off they have been taught that Gawd Awful "cadence" 
 Disengage the ABS on Wet snow or gravel only.
ProRally and Steamboat patches on:
Hmmmm... Don't totally agree with this in audi-lund...  ABS, esp the audi
ABS, Just plain won't work on ice, btdt...  Exponentially audiosing the
problem is that most quattros have a single rear circuit that operates on the
lowest cf rear wheel, that can spin you faster than not using abs at all,
lock is easy to control comparatively speaking..  The pedal goes to the floor
when no cf of friction, and now you have hydraulics at a point where any
traction coming up will throw the car waaaay out of whack.  This is becuz the
solenoids regain pulsing actuation quicker than the driver realizes he's back
to higer cf and yet his foot is on the floor...  I agree that cadence braking
(and Blizzack school TEACHES this) is just plain wrong....  Skid control on
ice is lockem up until the back wants to swap with the front, then release
then back on....   Cadence braking tends to send cars around, cuz most
hydraulic systems need some time to unlock, older brakes longer than newer
brakes, fronts faster than rears, discs faster than shoes,  fluid massively
affects this too....  Me, I put the car wherever there is something other
than ice, 1/2 in the ditch beats slide into neighbor...

Maximum traction on ice is locked tire in a straight line...  That has the
potential of spinning a car, so the trick is to lock as long as you can, then
unlock to gain the control then lock again....  Sound like cadence braking?
 I assure you, it ain't even close...  The theory behind cadence is that the
front stays compressed while braking....  On ice, that's about the biggest
oxymoron idea I heard in a long while...  You don't have enough cf to put the
front end at anything close to full compression, so why bother....  My
thoughts on ice is cheat, that's how I had some of the fastest lap times at
steamboat ice school, first time at the track (without the touted blizzacks
either).  On ice you have nothing to loose, and everything to gain
elsewhere...  I ate those snowbanks with PDQSHIP, on exit and braking...  The
idea is wherever maximum g's are that's where your tires should be....  In a
pinch guardrails slow cars down in a big way too.......  

Sand, gravel, ice and snow = ABS off....   Otherwise abs on....  The longer
you spend learning how to drive correctly, the more you activate that abs-off