Really Give Me Brakes?
We love our cars, and we love to take them to the track.
The Quattro Club has been especially good at sanctioning driving school events
at race venues across the country. We sometimes hear afterwards of horror
stories about brakes being destroyed during these events, tales of near-death
(at least to those that had them) experiences. Further, the earlier Audi
performance models such as the S4 and S6 had what many owners considered to be
inadequate brakes, even for the street. In response to this there’s a
significant cottage industry catering to Audi owners for brake upgrades. In
fact, one of the more common subjects for articles in the Quattro Quarterly has
been on that subject.
As technical director of BIRA (Brake Improvement Research
Association – see Quattro Quarterly Fall 2000), I am consistently asked if BIRA
(or other aftermarket) brakes are "adequate for track use". The concern seems to
be that tracking a street car would kill the brakes, that it's a safety issue
that any owner should consider before taking their car on the track. I'm going
to toss a completely different spin on this and no doubt start some serious
debate on the subject, but in my opinion any brakes that work properly
are adequate for track use. Yes, even the stock brakes.
Keep in mind that these track events are not competitions,
they're learning events. They are for us to go out and drive our street cars,
vehicles TOTALLY inappropriate for track use, around a local race track and go
fast(er). No one is going to notice if your car is a second per lap faster than
it was last time, or if it's a second a lap faster than your buddy's car. Even
if someone did notice, it's irrelevant. If going fast is really a need (or a
strong desire) for you, get into organized racing because these Q-club driving
events are not for you. Try SCCA (http://www.scca.org)
or NASA (http://www.nasaproracing.com).
Check your attitude at the Q-Club events door, please.
Since we’re not concerned about the fact that we're driving
faster than before, we need to take care of our equipment to be able to enjoy
the event. After all, isn't the whole point of these things to have fun? You've
heard the old racing saw, "In order to finish first, you must first be Finnish"
(oh, wait, that was Mikka). Actually, it’s "In order to finish first, you must
first finish." To do this, you must take care of your car and drive within its
limits, and that includes brakes. Taking care of the brakes may include slowing
down (horror!) in order to make your brakes stay within their temperature limits
and last the event's duration. Tell me, who's the guy out there having more fun:
the one that drives like a bat outta hell, destroys his brakes in two sessions,
and sits out the second day, or the guy that takes care of his car, goes a
second a lap slower (not that any will even notice) and makes it the full two
days?
I am significantly more impressed by a driver that
understands his/her own personal limitations, is in sync (Zen?) with what the
car is telling them, and drives appropriately, one that can make a car last for
the duration, not have to work on it every session, and stays off the walls. A
really good driver can take a totally stock car and go against any of us in the
most modded-out Stage 27x car. Count the number of laps they drive over the two
or three hours of track time out there, and you'll be surprised that this Good
Driver will put in more laps, go farther, have more track time, and thus
probably have more fun. Why? Because they are taking care of the equipment.
As I tell my students, "You can't win these events, but you
can certainly lose them." The 'lose' part is totally controlled by one major
piece of equipment, the MOST IMPORTANT piece of equipment in the car: the nut
behind the wheel. That nut has total control over the car's operating
parameters, including the brakes. Fancy brake setups, expensive brake fluid,
stainless steel lines, big tires, big wheels, air dams and splitters are all
meaningless fluff. Since the whole point is track TIME, doing it faster gives us
nothing, wins us nothing except maybe a mention on Internet Forums, which will
scroll off within a week to be forever ignored in the archives. How much money
is that worth to you?
To summarize (and not get off too far on a rant) all this
additive equipment is nothing when you consider we're in a non-competitive
environment. We get nothing by going faster, and we are all capable of showing
the discipline of driving within the car's limits. There's no trophy queen
waiting for us on the podium, and there's no Speedvision announcer waiting to
interview us. Besides, it's a heck of a lot more fun to make a slow car
go fast than to try and make a fast car go fast. Go slow in a stock car and no
one notices, it's expected. Go fast in a highly modified car raises no eyebrows,
as it's expected. Go slow in a highly modified car and you look like an idiot.
Go fast in a stock car and folks are impressed.
OK, so now that we've gotten beyond this we’ve decided to
mod the car anyway, let's say for cosmetic purposes (personal tastes.) What has
this gotten us for the track? If we still maintain our discipline and drive
within the limits of the car, all we've done is increase those limits to a
higher plane.
In context, consider brakes. Before now, we drove within
the limits of the stock brakes, and that required that we lift off the gas
sooner (horrors!), brake sooner (horrors!), and make sure we cool the brake
parts sufficiently before the next time we need it (yeah!). We were paying
attention to the car, and noticed that the car didn't really stop well at that
last turn, and that it's worsening slightly each time. The Good Driver is saying
to himself, "OK, I'm overheating the brakes, and the worsening tells me I'm not
rejecting enough heat before the next turn. I need to slow down to save the
equipment." We finished the event and had a heck of a time doing it.
So what does adding the Stage 27x brakes buy us? More
speed, more kinetic energy, more chances for balling up our little cars into a
length of steel Armco. Does going faster make us a better driver? Not at all,
I've met a lot of rich race drivers that couldn't drive worth a squat. They sure
were fast, though, in those mega-millions cars (ever watch the Ferrari Challenge
races? Hah!) Does going faster make us learn more? Nope, it's still all the same
idea of driving the right way, at the right locations, all within the limits of
the car. Does the Stage 27x brakes eliminate the need for being precise? Not at
all; in fact, quite the contrary.
Does the Stage 27x brakes eliminate our concerns for brake
system longevity and safety? ABSOLUTELY NOT.
All Stage 27x brakes will do for us is raise the bar a few
notches more. You can still overheat the brakes, you can still fade the pads,
and you can still wear out the components. All you've done now is raise the
SPEEDS at which those failures happen, and increased the outflow from your
pocketbook. Remember, raising the bar increases the distance you have to fall
when you screw up.
OK, so let's talk about reality.
Our cars are luxury cars that can weigh almost two tons,
sometimes more. Since many of us have modified the power in the car in that
quixotic Mutually Assured Destruction quest for “enough power” (clue: you’ll
never get there), we are capable of some serious speeds on even the shortest
straights. Problem is, I don't know of any road course that does not have a turn
at the end of a straightaway. So, you’re gonna have to use the brakes.
Unfortunately, all of our cars are equipped with loose nuts
behind the wheel; the level of tightening varies. Even though I contend that any
disciplined driver can drive these track lapping events with stock brakes, I
concede that at the speeds we can drive the stock brakes, while "adequate" with
discipline, are not "good". Because the stock brakes are designed for day-to-day
driving and the occasional single hard stop from highway speeds, they are not up
to the task of repeated stopping from high speeds as is required at these road
courses.
So what do you do about it? First of all, you pay attention
to what the car is telling you. The first indication of problems is brake pad
fade. This is when you've over-heated the brake pads beyond their designed
temperature specification, and they start to melt at the surface. This melting
transfers the pad's surface to the rotors (and make it feels like they're
warped). A melting pad does not have the friction coefficient as good as a
non-melting pad; this is noticed as increased pedal pressure and if not kept in
check a continued worsening of brake performance. Plain and simple, you've
overheated your brakes and the only resolution is to SLOW DOWN and not use the
brakes so hard. Many nuts think that they've boiled the brake fluid; this is not
usually true. It is hard to boil brake fluid in a stock car with stock brakes.
The pads will always fade first and since a fading pad is not generating as much
power, it's not generating as much heat.
A loose nut will continue to drive hard, won't back up the
stopping point, and will eventually completely slag the pads to the backing
plates until Loud Noises begin to happen. Or, a loose nut will not compensate
for the increased braking distances that come with fading the pads. In either
case, if the nut doesn't do something quick (like, maybe go home) Mr. Armco
awaits.
So, because our brake pads are made for normal everyday
driving, I think it's a fine idea to have a set of pads purchased specifically
for driving your car around a race track. This will allow you to do spirited
driving consistently lap after lap, within limits. Anything over and above this,
including BIRA designs, is for speed, not for safety. And I think you got my
point on more speed at lapping events...
OK, so there we are. Greg thinks that all stock braking
systems, with aftermarket pads and a properly tightened loose nut, are
“adequate” for track use. If you want some bigger brakes over stock they are by
definition certainly adequate for the track and will make you go faster, if
that's important to you, subject to the laws of Physics and Thermodynamics.
However, it's even possible for a heads-down loose nut to over drive aftermarket
brakes to infamy, and I bet that even the “best” megabuck brake systems can be
burned to a crisp in short order. However, for those same megabucks I can throw
a pretty nice beer party after the first day's event. That will slow down my
"competitors" a whole bunch more than aftermarket brakes will speed me up, and
I’ll be more popular to boot!
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