I know many race fans listen to their favorite driver(s) via scanner. By listening, you feel as though you are actually a part of the team. Your listening to a crew chief discuss possible adjustments with the driver in order to make the car better. That’s when a pit stop happens. Pit stops play are a very important part in the strategy in order to win a race.
Pit stops happen during a caution (yellow flag) or under green flag conditions – while the race is still running under normal speed. If you’ve ever wondered why teams don’t work on their cars, even if they’re on pit road, during a red flag (where the race has been stopped) – it’s because they are NOT allowed.
Once qualifying is complete, each teams gets to choose which pit stall they prefer in the order in which they qualified. Strategy also plays a huge part in this. The very first pit stall usually gets picked by the driver on Pole. It’s the most wanted pit stall. Depending on where the timing lines (scoring loops) are, openings to the pit wall, (which allows more space and less chance of running into another race car when pitting), actually a lot goes into consideration as to which pit stall a driver prefers.
Normally, teams are allowed six crew members over the pit wall to work on the car during a pit stop. Sometimes, NASCAR will allow a seventh crew member to go over to clean the windshield, if required. The normal six crew members allowed over the wall include: Two tire changers (front & rear), two tire carriers (front & rear) gas man, and the jack man. Not to mention, each pit stall has two NASCAR Officials assigned to watch for any pit violations – one for the rear, one for the front. An average, efficient pit stop calling for four tires and fuel only, can take anywhere between 13-15 seconds. If any type of adjustments are required (depending on the type of adjustment) it could prolong the pit stop, hence losing valuable time and a good spot on the track. Some drivers and crew chiefs will discuss that they will give up track position in order to fix an ill-handling race car.
If there is a pit violation, the driver will have to complete a “drive through” penalty, which means the driver will bring the car down pit road, at pit road speed, drive through without stopping, and go back out on the track, usually going a lap (or so) down. Another penalty could be, that the car could be held on pit road for a certain amount of time or laps by the NASCAR Official. The driver must always be consistent to stop inside the box of his pit stall. If either part of the car is over the lines, he is outside his pit box and is in violation. The timing of the crew must be right on, because once the jack man lets the jack down, that signals the driver to “GO!”
Pit road also has what is called timing lines, or scoring loops. This prevents drivers from speeding on pit road. Each track is different, depending on the size of pit road. Scoring loops embedded in the pit road concrete send an electrical signal when the transponder in the car passes via a process called electromagnetic induction. It’s the same process used to keep track of where the cars are during the race. The transponders are mounted inside the car. All teams have access to maps, at each track, showing all the timing lines and are allowed 5 mph over the “official” pit road speed.
As many of you are aware, there are some terms that may be confusing for what you are hearing over the scanner. Wouldn’t it be nice to actually know what the team is talking about? You may get mixed up thinking that “oh, I thought it was called this _____.” Hey, it happens!
Well, to help with the confusion some may experience, I thought I’d just throw out there some of the terms that is used quite a bit, or even barely, or even not at all – between the team on how they diagnose what type of adjustments are needed by the way the car is handling.
Track Bar - A track bar is a hollow steel tube approximately one and three-eighths of an inch in diameter. The length is adjustable and this moves the rear end housing from left to right. During pit stops the height of the bar’s mounting location on the chassis is what the crew works on.
Track Bar Adjustments – When a driver or crew chief calls for raising of the track bar, the car is tight and he is attempting to loosen the driver’s feel. By lowering the track bar, the feel will tighten up. This is used under loose conditions.
Round – Slang term for a way of making chassis adjustments utilizing the race car’s springs.
Oversteering (AKA as Loose) – Consider what happens when a race car enters a left turn at a high speed with decreased wedge — where the left-front and right-rear have more weight than the other two. The left turn evens out the difference in the weight on the two front wheels but intensifies the disparity in weight on the rear wheels. The rear wheels then don’t grip as well as the front wheels, which can cause the rear to swing out.
Understeering (AKA Tight or Push) - Rear end is “fishtailing”
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.
Aero Drag – 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.
Cross-Weight - The diagonally related weight between the left-rear and right-front wheels.
Wedge Adjustment – refers to adjusting the amount of force that bears down on a tire’s spring. Crews access the small holes in its rear window to tubes that go directly to springs in the suspension system.
Dirty Air – The air used and discarded by the lead car.
Clean Air – Up front leading. No “dirty air.” Nothing is blocking the air flow, undisturbed air allowing full range of “clean air” – helps cools engine, water temps.
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.
Chassis – The combination of a car’s floorboard, interior and roll cage.
Air Pressure – 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.”
Sway Bar – Sometimes called an “antiroll bar.” Bar used to resist or counteract the rolling force of the car body through the turns.
Trailing Arm – A rear suspension piece holding the rear axle firmly fore and aft yet allowing it to travel up and down.
Subtract Wedge (AKA to take wedge out) – reduce the tension on the left-rear wheel’s spring.
Adding Wedge (AKA to add more wedge) – Compressing the spring of a left-rear wheel puts more of the car’s weight on that corner.
Camber (AKA Toe) – refers to the vertical tilt of a wheel if you’re looking at it from the front or rear of the car. A wheel has zero or neutral camber if it’s perfectly perpendicular with the level ground.
Negative Camber (AKA Toe-Out)- top of the wheel is tilted toward the vehicle and the bottom slopes outward.
Positive Camber (AKA Toe-In) – top of a wheel is tilted outward from the vehicle and the bottom slopes in.
Hope this helps. Enjoy the race!
SOURCES: NASCAR Media, NASCAR.com, Google