WHAT IS A NAS"CAR"
What it take to make a car a "nascar"
Right now in Nascar there are three manufacturers
involved in the sport Ford, Chevy, and Dodge. but
what does it take to make the mom and dad mobile into a
racing demon. We will break down the car with a
graphic to allow youto know what is being talked about
ie restrictor
plates..etc. This graphic will give you the tools
needed to be knowledgeable of a Nas"car"
The original races were run on dirt
tracks that got rutted and bumpy. The unmodified
cars were not tough enough for this type of abuse, so
NASCAR began allowing modifications to the stock cars to
increase their durability. Over the years, more
and more modifications were made, sometimes to increase
safety and sometimes to improve competition. NASCAR
strictly controls all of these modifications. Cars
are checked for compliance with these rules at every
race. Why Your Taurus, Monte Carlo, And Grand Prix
Will Never Race In A Winston Cup Race by David Miller;
Circle Track; June 1999
There was a day when a racer could literally go to a
dealership and buy a race-ready car. That was a
time when stock-car racing was much closer to stock than
it is today. As race cars have evolved, they have, by
necessity, become less of a stock car and more of an
aerodynamic safety cage (just ask Richard Petty).
Many features in today's racing platforms have been
designed specifically for high-speed safety, and they
would be hard to incorporate in a street car. Roof flaps
are one such example. Roof flaps are
designed to keep a car from flying, and it would be
unlikely that this high-speed feature would have
any function on a passenger vehicle. Another example is
the rollcage. The 'cage does its job in a race car, but
it would be a gross overkill in a consumer model--think
of the loss of passenger space.
Today, NASCAR race cars have very little in common with
street cars. Almost every detail of a NASCAR car is
handmade. The bodies are built from flat sheet
metal, the engines are assembled from a bare block and
the frame is constructedfrom steel tubing.
The point is that we all look to racing for good
competition and brand-name supremacy. However, to
believe that what we see on the track bears much
resemblance to what we drive to the grocery store would
be wrong. Today's race cars have brand names on the
front bumper and authentic looking headlight decals on
the nose piece that tend to make the race cars resemble
a specific production car. They also have a
hood-to-rear-deck profile that resembles a car you may
own.
Yet, the comparisons between the two pretty much end
there.
So here we are with today's high-tech race car that has
proven to be worthy in both speed and safety, but it's
still called a stock car. The truth is that a Winston
Cup car only has a few things in common with a consumer
version of the same name. With that thought in mind,
Circle Track looked at a Winston Cup stock car to see
what is actually stock about it.
Engine
By NASCAR rules, the block and cylinder heads are
required to be of original equipment manufacture.
So both the block and heads come from Dodge, Ford or GM.
Rearend
The rearends used in the cars are still stock-production
type. For those who are unaware, Chevrolet, Pontiac, and
Ford all run a 9-inch Ford setup. Ratios of the gears,
of course, vary as needed at a given track.
Car Type
To run a car in Winston Cup competition, the car is
required to be available to the public as a consumer
production model. Both the Pontiac Grand Prix and
Chevrolet Monte Carlo have counterparts available to the
public. The Ford Taurus is also available to the
public but in a four-door model only.
The fact that the Taurus comes as a four-door is an
important point to note because of the other requirement
of a car type. The general profile of a production model
is theoretically intended to be maintained in a race-car
profile. The specific guideline is that the hood, roof,
and rear-deck surfaces should resemble the consumer
unit.
In the case of the GM passenger car, the profile is
roughly equivalent to the race car, but because the
street Taurus comes only as a four-door, some allowances
were necessary to make a race version of it. This
happened when the Thunderbird was phased out, and the
Taurus became the car Ford put forward. The big
difference is that the production four-door has a roof
that is taller than the race version.
Stock Cars
For the most part, examples cited here are the main
features that are still regarded as stock in a Winston
Cup car. It's important to note that for a race car, not
being stock is a good thing. Stock cars are not and
never will be vehicles that were meant to be in
circle-track competition. It's safe to say that this is
an axiom that applies to any racing done on any circle
track. The bottom line is that you can go out and pull
for your favorite brand name, but when you look at
a race car up close, don't expect it to be much of a
stock stock car.
Stock Cars?
Inside Anatomy of a NEXTEL Cup Car
1. If you peeled back the skin of a race car, you'd find
a metal cage the roll cage that is basically the
same shape as the car. This is the cocoon that protects
the driver in a violent accident, when the sheet metal
may be stripped away. This rollcage is for the safety of
racers who operate this baby in a 200-mph-plus
environment. Not even in your dreams will you attain
that kind of speed in your factory model. The cage
is fashioned out of hollow metal tubes that outline the
car's perimeter, roof line, doors and windows.
2. Rollbar padding is standard in race cars to keep
drivers from seeing stars if their helmets come in
contact with the rollbars. The closest thing you have in
your racy street car is a plush headliner.
3. The Unmarked White Lever: is the master on-off
ignition switch that turns all the power off to the
motor and the whole car. Some people call it the kill
switch. Hopefully, the only time it's used is when the
car cover is put on at night. But if in an
accident, the rescue people can get to that, and if the
car is smoldering or on fire, they can turn it off. This
is just a mega version of your ignition switch.
4. The outside air source for racers is via an opening
like this, called a NACA duct. It allows the air to be
directed at the driver. No, it's not like your air
conditioner. These fire-breathing chariots don't have
such things. The temperature of the air that comes
into the car is whatever Mother Nature is providing at
the time.
5. Drivers' helmets are, of course, a required part of
the racers' garb. They are high-tech, high impact,
absorbing units that can take a lot. Considering the way
most people drive, maybe every driver on the road should
have one.
6. The average street driver can't fathom the complexity
of driver seats in race cars, which are typically
custom-fit for a given racer. That's right, the racer is
measured, so the seat Literally fits like a glove. The
idea is to make the driver a part of the seat and the
seat a part of the car to make the driver more secure.
Doesn't look like the kind of thing that would be fun in
a street car-it would probably be a little uncomfortable
for the wife and kids, wouldn't you say? They're made of
aluminum and custom-fitted for each driver. They're more
of a bucket than a seat, wrapping around the driver's
thighs, rib cage and, in some cases, shoulders as well.
The idea is to support the driver through a four-hour,
jarring ride and hold him in place during a crash.
7. Race-car safety belts are much different from those
found in a factory car. Instead of this, drivers are
strapped in with a five-point harness, similar to those
worn by fighter pilots. These super-tough nylon belts
are a five-point latch-and-link harness system. They
have two connections at the shoulder, two at the lap,
and one at the crotch (ouch).
8. Don't look for your comfy digital-readout
color-coordinated gauges in this car. Race-car driver
gauges provide data such as engine rpm, water
temperature and fuel pressure. And believe it or not,
there is no speedometer. Some dashboard gauges are
installed at an angle, so when the engine is running
properly, the needles on all the gauges will point
straight up. Because drivers have only a split second to
glance at the dash during a race, tilting the gauges
helps them spot a problem quickly.
The switches are basic toggle units that control items
such as pumps, fans, and ignition systems (race cars
have two ignition systems). No, they're not as glamorous
as the ones in a factory model, but they don't have to
control electric seats, windows, or CD players.
A. Ignition Switch:
Start Switch and Second Ignition Switch. The flip of a
switch starts the ignition. If the first ignition switch
fails, there's a backup.
* Start - it doesn't take a key to start the car. Just
flip up the toggle switch that's on the far left.
That turns the engine over.
It doesn't make the sound of the engine starting yet.
All you hear is the click of the starter hitting the
flywheel.
* Ignition (1) - turns on the ignition box and cranks
the motor. The engine rumbles as it's given juice andthe
electricity sparks.
* Ignition (2) - is a backup in case the first one
fails.
B. Brake Fan Switch:
Cool Rear - turns on the fan for the rear end to keep
the back end of the car cool.
* Accessory - any electric accessory the driver wants.
On some cars it's the radiator fan,
so when the car slows down and there's not enough air
coming in to cool the motor, the fan helps keep the
motor cool.
C. Oil Pressure:
System runs ideally at 70-80 PSI. If the engine's oil
pressure falls below 20 pounds, a red light will come
on, to catch the driver's eye without looking at the
gauge. A better look at the gauge is needed if something
smells. If the light comes on, it's usually
too late to do anything about it. It's a problem that's
internal to the engine and it's usually
catastrophic failure.
D. Oil Temperature:
Acceptable temperature is 250-270 degrees F. No more
than 300 degrees.
E. Water Temperature:
Needs to be about 190 to 210 degrees. When it starts to
creep up over 220 is when there's a problem with it
getting too hot. If it's really cold outside, tape is
put over the nose of the car (which cuts off air) to get
the optimum temperature. The car runs best keeping the
same temperature range all the time.
F. Fuel:
Ideal range is 7-8 lbs. This tells what the fuel
pressure is, not how much fuel is left. With too much
fuel pressure, it has to be regulated down. It's a
diagnostic-type thing. Basically, it kind of tells any
kind of problem with the fuel. If it's low, it may be a
problem with the fuel line. Or out of fuel. You see guys
trying to run races and get two more laps out of a fuel
stop. Sometimes if it drops, there might be enough left
to get back around the track. It might run three
more laps. Or sometimes it'll glitch, and it's over.
G. Driver Fan Switch:
A flip recycles air and blows cool air into the driver's
helmet.
 |
Kill Switch: On steering wheel.
Added in 2000 after several stuck-throttle-related
accidents, it kills the engine. Tachometer:
There's a certain speed limit on pit road, and without a
speedometer the tachometer [which measures rpm
(crankshaft revolutions per minute)] is used to
determine the pre-set speed. During a pace lap; with the
car in a certain gear the rpm reading is determined that
should hit that speed. A driver's butt tells him if he's
running the right rpms or not. It's by feel, and his but
tells you when it's time to change gears. Volts: Tells
how many amps the battery is putting out. With a 12-volt
battery and pulling 10 volts, it's not charging good
enough and the car needs a better alternator. If it's
overcharging, it's liable to burn something up.
|
9. There is no window glass on the driver's side. At
high speeds that helps keep the car from flipping if it
spins at a certain angle. Because there are no doors on
the cars, drivers climb in through the window. Window
nets are put in race cars for two basic reasons: to
contain the driver and prevent debris from entering the
car. They're great safety devices but aren't much good
for keeping out rain. Oh yeah, these guys only drive in
good weather.
10. Steering wheels in a race car are not equipped with
convenient switches for cruise control or the radio.
Heck, they don't even have an air bag in them, only a
center of high-impact foam, and the wheel itself is
foam-covered.
11. Here's something your car actually has in it: an
energy-absorbing steering column. The design is a bit
different, but the principle is the same: it's meant to
be functional in an accident. Built for
speed
Accessories:
Race cars are Spartan inside, without creature comforts
such as upholstery, glove compartments or cup holders.
Like Dick Trickle, three-time Winston Cup champion David
Pearson (1966, 68-69) had a cigarette lighter on the
dash of his car. Pearson liked to smoke during caution
flags.
Doors:
Up until the late 1970s, race cars had real doors that
were welded shut. That changed after cars were downsized
in the early 1980s. Today, the body shape may look like
there's a door there, but it's a complete, seamless
skin.
Engine:
The stock car's V8 engine is nearly unchanged since the
days of the Model A, with no electronics allowed.
The passenger car has a 3800 V6 supercharged engine with
fuel injection. Race car engines are normally aspirated.
They're also rebuilt after running just a few hundred
miles. The engine parts are specialized made to
withstand high rpms (7,800) and lots of horsepower
(750). A racing engine costs $35,000 to $40,000, and
almost every team builds its own.
 |
A Dodge NASCAR engine during assembly in the engine
shop. Dodge provides the engine block and cylinder head
for the engines. They are based on a 340-cubic-inch
(5.57-liter) V-8 engine design that was produced in the
1960s. The engine in the NASCAR race car is
probably the most crucial component. It has to make huge
amounts of power for hours on end, without any failures.
You might think these engines have nothing in common
with the engine in your car.
These engines actually share many features with
street-car engines.
The actual engine blocks and heads are not made from the
original tooling. They are custom-made race-engine
blocks, but they do have some things in common with the
original engines. They have the same cylinder bore
centerlines, the same number of cylinders and they start
out at the same size (they get a little bigger during
the building process). Like the original
engines, the valves are driven by pushrods. |
The engines in today's NASCAR race cars produce upward
of 750 horsepower, and they do it without turbochargers,
superchargers or particularly exotic components. How do
they make all that power?
Here are some of the factors:
1. The engine is large 358 cubic inches (5.87 L). Not
many street-cars have engines this big, and the ones
that do usually generate well over 300 hp.
2. NASCAR engines have extremely radical cam profiles that open the intake
valves much earlier and keep them open longer than
in streetcar engines. This allows more air to be packed
into the cylinders, especially at high speeds.
3. The intake and exhaust are tuned and tested to
provide a boost at certain engine speeds. They are also
designed to have very
low restriction that is, to provide little resistance
to the gases flowing down the pipe. There are no
mufflers or catalytic
converters to slow the exhaust down, either.
4. They have carburetors that can let in huge volumes of
air and fuel there are no fuel injectors on these
engines.
5. They have high-intensity, programmable ignition
systems that allow the spark timing to be customized to
provide
the most possible power.
6. All of the subsystems, like coolant pumps, oil pumps,
steering pumps and alternators, are designed to run at
sustained high speeds and temperatures.
When these engines are machined and assembled, very
tight tolerances are used (parts are made more
accurately) so that everything fits perfectly. When an
engine (or any part, for that matter) is designed, the
intended dimensions of the part are given along with the
allowable error in those dimensions. Making the
allowable error small tightening the tolerances
helps the engine achieve its maximum potential power and
also helps reduce wear. If parts are too big or too
small, power can be lost due to extra friction or to
pressure leakage through bigger than necessary gaps.
Several tests and inspections are run on the engine
after it is assembled:
1. It is run on the dynamometer (which measures engine
power output) for 30 minutes to break it in.
The engine is then inspected. The filters are checked
for excess metal shavings to make sure no abnormal wear
has taken place.
2. If it passes that test, it goes back on the
dynamometer for another two hours. During this test, the
ignition timing is dialed in to maximize power, and the
engine is cycled through various speed and power ranges.
3. After this test, the engine is inspected thoroughly.
The valve train is pulled and the camshaft and valve
lifters are inspected. The insides of the cylinders are
examined for abnormal wear. The cylinders are
pressurized and the rate of leakdown is measured to see
how well the pistons and seals hold the pressure. All of
the lines and hoses are checked.
Only after all of these tests and inspections are
finished is the engine ready to go to the races.
Insuring the reliability of the engine is critical
almost any engine failure during a race eliminates the
chance of winning.
Fire Extinguisher:
It's required inside the driver's compartment, within
easy reach of the driver.
Fuel Overflow Tube:
Passenger cars have these, too, but they're under the
car. Race cars don't have fuel gauges, so when the gas
tank is full, the excess spills out. A crew member
catches the overflow in a can, then measures that amount
so the crew knows exactly how much is in the car and can
precisely calculate gas mileage. A race car's gas tank
holds 22 gallons. The gas comes from a central
tank to ensure teams don't add additives. The gas cans
used to refill cars hold 11 gallons each and weigh about
70 pounds when full. Racing gas is leaded, 104 octane.
Development of an unleaded racing fuel is a year or two
away.
Headlights:
Upon closer inspection, those headlights on stock cars
aren't headlights at all. They're decals. The decals,
added in recent years, are backed by the automakers
eager to accentuate the resemblance between race cars
and passenger cars. When NASCAR holds races at
night, drivers can see because the tracks are so well
lit.
Hole Near Back Windshield:
It's not an air vent; it's a spot to slip a tool in to
make adjustments that affect the way the car handles.
One hole is to make adjustments to the springs. A second
hole lets you slip a tool in to adjust the track bar.
The track bar affects the rear suspension.
Rear Spoiler:
Spoilers have been a feature on race cars for decades,
but the size, shape and angle have varied over time.
As speeds have grown, so has spoiler size. At all tracks
except Daytona and Talladega, they're used to create
downforce and improve traction. At those two giant
superspeedways, where carburetor restrictor plates are
required to slow the cars, traction isn't a
problem, so the spoilers are used to create drag and
further slow speeds. The size and shape vary
slightly by car make because they must conform to the
shape of the trunk.
Roof Flaps:
One of the most effective safety innovations of recent
years, the roof flaps basically serve as an air brake
similar to the flaps that pop up on the wings of an
airplane when it lands. The roof flaps deploy when the
car spins backward, and the force of the air pushes them
up. That creates downforce, which helps keep a car that
is spinning out of control at 180 or 200 mph from flying
up in the air like a kite.
 |
Most of the teams remove the air from the tires and
replace it with nitrogen. Compressed nitrogen contains
less moisture than compressed air. When the tire heats
up, moisture in the tire vaporizes and expands, causing
the pressure inside the tire to increase. Even small
changes in tire pressure can noticeably affect the
handling of the car. By using nitrogen instead of air,
the teams have more control over how much the pressure
will increase when the tires heat up.
Tires:
From an engineering standpoint, tires are the single
biggest difference between a passenger car and a race
car. Like the tires on your car, NASCAR tires are
radial tires, but that is about the only similarity.
The tires on a NASCAR race car have some very special
requirements. You notice the width first roughly a
foot, as opposed to five or six inches for a regular car
and the fact that they are treadless. Both the wider
footprint and lack of grooves help provide more traction
and grip. |
On a dry track, tires can generate more traction if more
of their sticky rubber is in contact with the ground.
Putting a tread pattern on the tire helps in wet
weather, but in dry weather it is better to have the
whole tire touching the ground. That's why NASCAR races
stop whenever the track is wet.
NASCAR's top series uses only Goodyear racing tires,
which cost about $350 apiece and are worn out after 75
to 100 miles, although track surface and driver skill
affect tire wear. They don't weigh as much as you'd
think because of their thin construction. Because
the car always turns left, the right-side tires bear
more strain and are softer.
Rubber match:
The Winston Cup tire setup comparison below is from
Michigan International Speedway. The passenger car tire
used is a 195/60R15 Goodyear Eagle GTII.
Nextel Cup Tire
Passenger Car Tire
Minimum race cold pressure
- Left side: 28 psi.
- 30 to 35 ps
- Right front: 46 psi. Right rear: 44 psi.
Tire life
-
50,000 miles
Competitive life
- Left side: 150 miles. Right side: 100 miles.
Tread width
Tread width
- All tires: 6.8 inches.
- Left side: 11.5 inches. Right side: 11 inches
Weight
Weight
All tires:26.2 pounds
- Left side: 24.0 pounds. Right side: 24.3 pounds.
Circumference
Circumference
- Left side: 87.3 inches. Right side: 88.6 inches.
All tires:77.2 inches
Price
- $386 each.
$65 to $100 each.
Windshield Glass:
It's not glass, but a type of plastic known as Lexan.
Similar to windows in an airplane, it's lighter and
tougher to break than glass. For added support, there is
a roll bar on each side of the windshield. An
extra bar of reinforcement has been mandated for the
center of the windshield in 1996 to keep large pieces of
debris from flying into the car.
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