Traction Control & Racing

[Frederic Breitwieser]

> feedback driven.  Are these even possibilities, or have I been wasting
> so many free brainwaves on this?

Hey Scott!

I read your post several times, and I didn't quite see what your
traction control idea was... but maybe I need new glasses.  I saw a lot
about "ideal street car" and some bits about NO2, but that's okay, we
can discuss this anyway, but I warn you (and others), I'm highly
opinionated in this particular subject, and more so now that I've had
some experience with it.  Anyhoo -

Traction control by the OEMs (Caddy, Lexus, BMW, Nissan) etc are all
designed to resolve two issues - bad drivers screwing up, and good
drivers screwing up :)  And the common factor is... yes, you got it! 
"Screwing up".  This "safety device" gets the OEM's kudo's, marketing
"brag rights", and more profit.  And, it makes the government happy, and
lowers our car insurance 12 bucks a month, so its a win, win, win
situation, right?  :)

What traction control is all about is reducing the power to the wheels,
or specific wheel, when the tire's adhesion ability is exceeded.  There
is a lot of potential ways to achieve this, the most common by the OEMs
is to chop ignition to one or more cylinders in a logical fashion,
reducing flywheel power.  This is good because while hard on the engine,
it won't destroy it the same way as cutting fuel to an injector, and
leaning the hell out of the engine.  BOOM!  There are some who believe
applying brakes is a good form of traction control - bad - because it
would be very difficult for a vehicle to determine if its sliding
forward or sideways, and much to complex to make reliable and cheap,
which is the OEM goal.  Therefore, applying brakes automatically by an
ECM could result in a slight slide (driver fuckup) turning into a slide
off the road over a cliff, into the ocean (worse case).

The best form of traction control, is driver experience.  Personally I
think parallel parking should be removed from drivers ed courses, and
all potential drivers should be forced to slalom a camaro through cones
sitting in 3" deep of water for 20 laps.  Nothing ever beats
experience.  This is why Andrette wins more often than other guys.  THis
is why John Force has a collossal career in the NHRA, as do other guys
in different types of racing leagues.  Practice, practice, practice.

The problem with racing vehicles, like any car for that matter, its a
massive set of compromises.  If you want to drag race, the vehicle would
be totally different than a 200 MPH slolam racer.  Drag cars need the
front/rear weight balance different than a midengine rally car, and the
tires are of course different.  Its very difficult to achieve both. 
I've seen a few radical street machines over the years that did
accelerate extremely well, and cornered extremely well, but still, its a
compromise.

The most common form of traction enhancement in racing is two things -
more tire - and more downforce.  The problem for a street car, is the
DOT limits the tires we can use from optimum, roads are not flat, and
under 100 MPH, there is not enough downforce to make a 1800lb 600HP race
car make 315/35R17's stick to the road effectively, experienced driver
or not.

Anyway, instead of ranting on and on, I think my thoughts are clear -
driver experience is the best traction control there is.  Join the SCCA
and do weekend slolams every saturday for a year, and take the same car
to a 1/4 mile on Sunday, and practice, practice, practice.  The better
you know your car and its limitations as its configured, the better off
you will be, every time.


-- 

Frederic Breitwieser
Xephic Technology
769 Sylvan Ave #9
Bridgeport CT 06606

Tele: (203) 372-2707
 Fax: (603) 372-1147
Web: http://xephic.dynip.com/