Know Your Flags

What do each of the flags and their colors mean?
Green: Start
Yellow: Caution; slow, hold position
Black: Pull into the pit for consult
Black/white stripe:
not being scored for laps completed, failing to obey a black flag
Red: Stop
Blue/yellow-orange
stripe: Move to another lane/Slower traffic move over
Yellow/red stripes: Oil on track
White: Entering last lap
Black/white checkered:
The race is finished
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And More
about
FLAGS
and what do they exactly mean
Green -
The starting flag, and the signal to start the race, or if it was interrupted,
the signal to resume the race.
Yellow -
Caution, be careful; something is wrong on the track. This could be an accident,
wreckage, oil on the track, a stalled car, weather, or any other unsafe
condition.
Black -
Pull into the pits, your car is not safe, you are not getting up to a fast
enough speed, or you have broken a racing rule and you are being penalized.
Black-&-White Crossed -
You are no longer being scored, because you are not obeying the black flag,
essentially, you are out of the race.
Red -
Every driver must stop his car. The race has been halted, often because of
weather conditions, or a bad accident. Under red flag conditions, teams are
usually not allowed to pit and work on the race cars.
Blue with Yellow Line -
You need to move over and let the faster cars pass you, you are apparently going
to slow and holding up the field.
Yellow with Red Line -
The track has oil or some kind of fluid on the track and slow down.
White -
When the white flag is shown, there is only one lap left to race.
Checkered -
The end of the race, this is the flag the drivers have been racing for, usually
for several laps or hours... A welcome sight to the leader.
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Nextel Cup racing, as does any other professional sport,
has a language all its own. The meaning and usage of the terms specific to the
sport pop up through any explanation of its racing action. The following is a
short list of basic terms you might hear around a Nextel Cup garage in 2004:
AERO PUSH
When following another vehicle closely, the airflow off the lead vehicle does
not travel across the following one(s) in a normal manner. Therefore, downforce
on the front of the trailing vehicle(s) is decreased and it does not turn in the
corners as well, resulting in an "aero push." This condition is more apparent on
the exit of the turns.
AERODYNAMIC DRAG
A number that is a coefficient of several factors that indicates how well a race
vehicle will travel through the air and how much resistance it offers. Crewmen
work to get the best "drag horsepower" rating they can, determining how much
horsepower it will take to move a vehicle through the air at a certain
mile-per-hour rate. At faster speedways teams strive to get the lowest drag
number possible for higher straightaway speeds.
AIR DAM
A strip that hangs under the front grill, very close to the ground. It helps
provide downforce at the front of the car.
AIR PRESSURE
With the advent of radial tires with stiffer sidewalls, changing air pressure in
the tires is used as another setup tool that is akin to adjusting spring rates
in the vehicle's suspension. An increase in air pressure raises the "spring
rate" in the tire itself and changes the vehicle's handling characteristics. If
his race vehicle was "tight" coming off a corner, a driver might request a
slight air pressure increase in the right rear tire to "loosen it up."
BACK MARKER
A car running off the pace near the rear of the field.
BALANCE
When a car doesn't tend to oversteer or understeer, but goes around the
racetrack as if its on rails, it's said to be in balance.
BANKING
The sloping of a racetrack, particularly at a curve or a corner, from the apron
to the outside wall. Degree of banking refers to the height of a racetrack's
slope at the outside edge.
CAMBER
Camber addresses the angle at which a tire makes contact with the track surface.
"Positive camber" indicates the angle of the tire is tilted away from the
vehicle's centerline while "negative camber" indicates the tire is tilted toward
the centerline. A typical oval track setup would have positive camber in the
left front and negative camber in the right front to help the vehicle make
left-hand turns.
CAMSHAFT
A rotating shaft within the engine that opens and closes the intake and exhaust
valves in the engine.
CHASSIS
The combination of a car's floorboard, interior and roll cage.
CHASSIS ROLL
The up-and-down movement caused when a car travels around corners at high
speeds. The side of the car facing the turn becomes lighter while the extra
weight goes toward the outside of the turn.
CONTACT PATCH
The part of the tire that's actually touching the road.
DIRTY AIR
The air used and discarded by the lead car.
DOWNFORCE
The air pressure traveling over the surfaces of a race vehicle creates "downforce"
or weight on that area. In order to increase corner speeds teams strive to
create downforce that increases tire grip. The tradeoff for increased corner
speeds derived from greater downforce is increased drag that slows straightaway
speeds.
DRAFT
The aerodynamic effect that allows two or more cars traveling nose-to-tail to
run faster than a single car. When one car follows closely, the one in front
cuts through the air, providing less resistance for the car in back.
DRAFTING
The practice of two or more cars, while racing, to run nose-to-tail, almost
touching. The lead car, by displacing the air in front of it, creates a vacuum
between its rear end and the nose of the following car, actually pulling the
second car along with it.
DRAG
The resistance a car experiences when passing through air at high speeds. A
resisting force exerted on a car parallel to its air stream and opposite in
direction to its motion.
ENGINE BLOCK
An iron casting from the manufacturer that envelopes the crankshaft, connecting
rods and pistons.
FABRICATOR
A person who specializes in creating the sheet metal body of a stock car. Most
teams employ two or more.
FIREWALL
A solid metal plate that separates the engine compartment from the driver's
compartment of a race car.
FRONT CLIP
The front-most part of the race car, starting with the firewall.
FUEL CELL
A holding tank for a race car's supply of gasoline. Consists of a metal box that
contains a flexible, tear-resistant bladder and foam baffling. A product of
aerospace technology, it's designed to eliminate or minimize fuel spillage.
GROOVE
Slang term for the best route around a racetrack; the most efficient or quickest
way around the track for a particular driver. The "high groove" takes a car
closer to the outside wall for most of a lap, while the "Low groove" takes a car
closer to the apron than the outside wall. Road racers use the term "line."
Drivers search for a fast groove, and that has been known to change depending on
track and weather conditions.
HAPPY HOUR
Slang term for the last official practice session held before an event. Usually
takes place the day before the race and after all qualifying and support races
have been staged.
HANDLING
Generally, a race car's performance while racing, qualifying or
practicing. How a car "Handles" is determined by its tires, suspension geometry,
aerodynamics and other factors.
INTERVAL
The time-distance between two cars. Referred to roughly in car lengths, or
precisely in seconds.
LAPPED TRAFFIC
Cars that have completed at least one full lap less than the race leader.
LOOSE
(Also referred to as "free" or "oversteer.") A condition created when the
back end of the vehicle wants to overtake the front end when it is either
entering or exiting a turn. In qualifying mode teams walk a fine line creating a
setup that "frees the vehicle up" as much as possible without causing the driver
to lose control.
MARBLES
(Also referred to as "loose stuff.") Bits of rubber that have been shaved
off tires and dirt and gravel blown to the outside of a corner by the wind
created by passing vehicles comprise the "marbles" that are often blamed by
drivers for causing them to lose control.
NEUTRAL
A term drivers use when referring to how their car is handling. When a car is
neither loose nor pushing (tight).
OVERSTEER
See Loose
PIT ROAD
The area where pit crews service the cars. Generally located along the front
straightaway, but because of space limitations, some racetracks sport pit roads
on the front and back straightaways.
PIT STALL
The area along pit road that is designated for a particular team's use during
pit stops. Each car stops in the team's stall before being serviced.
POLE POSITION
Slang term for the foremost position on the starting grid, awarded to the
fastest qualifier.
PUSH
(Also referred to as "tight" or "understeer.") "Push" is a condition that
occurs when the front tires of a vehicle will not turn crisply in a corner. When
this condition occurs, the driver must get out of the throttle until the front
tires grip the race track again.
QUARTER PANEL
The sheet metal on both sides of the car from the C-post to the rear bumper
below the deck lid and above the wheel well.
REAR CLIP
The section of a race car that begins at the base of the rear windshield and
extends to the rear bumper. Contains the car's fuel cell and rear suspension
components.
RESTRICTOR PLATE
An aluminum plate that is placed between the base of the carburetor and the
engine's intake manifold with four holes drilled in it. The plate is designed to
reduce the flow of air and fuel into the engine's combustion chamber, thereby
decreasing horsepower and speed.
ROOF FLAPS
These flaps are sections at the rear of a race vehicle's roof that are designed
to activate, or flip up, if the air pressure flowing across them decreases. In
the case of a vehicle turning backwards, the tendency for an uninterrupted flow
of air is to create lift. The roof flaps are designed to disrupt that airflow in
attempt to keep the vehicle on the ground.
ROUND
Slang term for a way of making chassis adjustments utilizing the race car's
springs. A wrench is inserted in a jack bolt attached to the springs, and is
used to tighten or loosen the amount of play in the spring. This in turn can
loosen or tighten the handling of a race car.
SETUP
Slang term for the tuning and adjustments made to a race car's suspension before
and during a race.
SHORT TRACK
Racetracks that are less than one mile in length.
SILLY SEASON
Slang for the period that begins during the latter part of the current season,
wherein some teams announce driver, crew and/or sponsor changes.
SPOILER
(Also referred to as a "blade.") The spoiler is a strip of aluminum that
stretches across the width of a race vehicle's rear decklid. It is designed to
create downforce on the rear of the vehicle, thereby increasing traction.
However, the tradeoff, again, is that more downforce equals more aerodynamic
drag, so teams attempt, particularly on qualifying runs, to lay the spoiler at
as low an angle as possible to "free up" their vehicles for more straightaway
speed.
STAGGER
Stagger is a concept that has largely been eliminated with the use of radial
tires. It refers to the difference in tire circumference between the left- and
right-side tires on the vehicle. Typically, the left-side tires would be a
smaller circumference than the right-side tires to "help" the vehicle make
left-hand turns.
STICK
Slang term used for tire traction.
STICKERS
Slang term for new tires. The name is derived from the manufacturer's
stickers that are affixed to each new tire's contact surface.
STOP 'N' GO (BLACK FLAGGED)
A penalty, usually assessed for speeding on pit road at the appropriate speed
and stopped for one full second in the team's pit stall before returning to the
track.
SUPERSPEEDWAY
A racetrack of one mile or more in distance. Road courses are included.
Racers refer to three types of oval tracks. Short tracks are under one mile,
intermediate tracks are at least a mile but under two miles and superspeedways
are two miles and longer.
SWAY BAR
Sometimes called an "antiroll bar." Bar used to resist or counteract the rolling
force of the car body through the turns.
TEMPLATE
A device used to check the body shape and size to ensure compliance with the
rules. The template closely resembles the shape of the factory version of the
car.
TIGHT
Also known as "understeer." A car is said to be tight if the front wheels lose
traction before the rear wheels do. A tight race car doesn't seem able to steer
sharply enough through the turns. Instead, the front end continues through the
wall.
TOE
Looking at the car from the front, the amount the tires are turned in or out. If
you imagine your feet to be the two front tires of a race car, standing with
your toes together would represent toe-in. Standing with your heels together
would represent toe-out.
TRACK BAR
(Also referred to as a "Panhard bar.") This bar locates the vehicle's rear end
housing from left-to-right under it. In calibrating the vehicle's "suspension
geometry," raising or lowering the track bar changes the rear roll center and
determines how well it will travel through the corners. During races, this
adjustment is done through the rear window using an extended ratchet. Typically,
lowering the track bar will "tighten" the vehicle and raising the track bar will
"loosen" it.
TRAILING ARM
A rear suspension piece holding the rear axle firmly fore and aft yet allowing
it to travel up and down.
TRI-OVAL
A racetrack that has a "hump" or "fifth turn" in addition to the standard four
corners. Not to be confused with a triangle-shaped speedway, which only has
three distinct corners.
TURBULANCE
Air that trails behind a race car and disrupts the flow of air to the
cars behind it.
UNDERSTEER
See Tight
VALANCE
(Also referred to as "front air dam.") This is the panel that extends below the
vehicle's front bumper. The relation of the bottom of the valance, or its ground
clearance, affects the amount of front downforce the vehicle creates. Lowering
the valance creates more front downforce.
VICTORY LANE
Sometimes called the "winner's circle." The spot on each racetrack's infield
where the race winner parks for the celebration.
WEDGE
Refers to the relationship from corner-to-corner of the weight of the
race vehicle. Increasing the weight on any corner of the vehicle affects the
weight of the other three corners in direct proportion. Weight adjustments are
made by turning "weight jacking screws" mounted on each corner with a ratchet. A
typical adjustment for a "loose" car would be to increase the weight of the left
rear corner of the vehicle, which decreases the weight of the left front and
right rear corners and increases the weight of the right front. A typical
adjustment for a "tight" vehicle would be to increase the weight of the right
rear corner, which decreases the weight of the right front and left rear and
increases the weight of the left front.
WEIGHT JACKING
The practice of shifting a car's weight to favor certain wheels.
WIND TUNNEL
A structure used by race teams to determine the aerodynamic efficiency of their
vehicles, consisting of a platform on which the vehicle is fixed and a giant fan
to create wind currents. Telemetry devices determine the airflow over the
vehicle and its coefficient of drag and downforce.
Credit to NASCAR.com for glossary
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