Glossary
Racing terms, explained.
62 words you’ll hear in the paddock, at the drivers’ meeting and in your data, from apex to slip angle.
62 of 62 terms
A
B
- Black flageventA black flag tells a driver to enter the pits; pointed at you it is personal, while shown to all cars it can stop the whole session.
- Brake beddingvehicleBrake bedding is a break-in routine that heats new pads and rotors to lay an even layer of pad material onto the rotor faces.
- Brake biasvehicleBrake bias is how the total braking force is split between the front and rear axles, usually expressed as a front percentage.
- Brake fadevehicleBrake fade is a loss of stopping power from overheated brakes, felt as a pedal that goes hard and ineffective or long and soft.
- Braking pointdrivingThe braking point is the spot where you first apply the brakes before a corner, usually tied to a fixed marker like a board or crack.
C
- CambervehicleCamber is the tilt of a wheel seen from the front; negative camber means the top of the tire leans in toward the car.
- CastervehicleCaster is the backward tilt of the steering axis seen from the side, which gives self-centering steering and adds camber as you turn.
- ChicanedrivingA chicane is a quick left-right or right-left sequence of corners, often added to slow cars before a fast section.
- ConsistencydataConsistency is how closely your lap times and inputs repeat from lap to lap, often measured as the spread between your laps.
- Cool-down lapsafetyA cool-down lap is a slower lap at the end of a session that lets brakes, tires, engine and driver come down from track temperatures.
- Corner weightsvehicleCorner weights are the loads on each of the four tires measured on scales, used to balance a car's chassis setup.
- Cross-weightvehicleCross-weight is the share of a car's weight on one diagonal pair of tires, with about 50 percent the usual target for road courses.
D
- Decreasing-radius cornerdrivingA decreasing-radius corner tightens as you go through it, so the exit is sharper than the entry and catches out drivers who enter too fast.
- Delta timedataDelta time is the live gap between your current lap and a reference lap, shown as plus (slower) or minus (faster) seconds.
- Double apexdrivingA double apex is a long corner taken with two separate clipping points, often with a slight drift out to the middle between them.
- Drivers' meetingeventThe drivers' meeting is the mandatory pre-event briefing covering flags, passing rules, schedule and track-specific safety procedures.
E
F
G
H
- HairpindrivingA hairpin is a very tight corner that turns the car through roughly 180 degrees, usually taken in a low gear after heavy braking.
- Heel-toe downshiftdrivingA heel-toe downshift uses one foot to brake and blip the throttle at once, matching engine speed to the lower gear for a smooth shift.
- Hot tire pressurevehicleHot tire pressure is the inflation pressure measured right after a session, when the tires are at working temperature.
- HPDEeventHPDE (high performance driver education) is a structured, non-competitive track event where drivers learn on track, often with an instructor.
I
L
- Lap timedataLap time is the time taken to complete one full circuit, measured from one crossing of the start/finish line to the next.
- Late apexdrivingA late apex clips the inside of a corner after its geometric middle, trading a little entry speed for an earlier, straighter exit.
- Lateral gdataLateral g is the sideways acceleration a car experiences while cornering, measured in multiples of gravity.
- Lift-off oversteervehicleLift-off oversteer is the rear stepping out when you suddenly lift off the throttle mid-corner, as weight shifts forward off the rear tires.
- Longitudinal gdataLongitudinal g is acceleration along the car's length: positive when speeding up and negative under braking, measured in multiples of gravity.
M
O
- Off-track recoverysafetyOff-track recovery is how you safely handle the car leaving the pavement: slow down in a straight line and rejoin only when it is safe.
- OversteervehicleOversteer is when the rear tires lose grip before the fronts, so the car turns more than you asked and the back swings outward.
P
- Pit laneeventThe pit lane is the area beside the track where cars enter and leave sessions, with strict speed limits and entry and exit rules.
- Point-byeventA point-by is a hand signal from the car in front telling a following driver it is safe to pass, and on which side.
- Polar moment of inertiavehiclePolar moment of inertia is a car's resistance to rotating about its vertical axis, set by how far its mass sits from the center.
R
- Racing flagseventRacing flags are signals shown by corner workers to warn drivers of hazards and control the session, from green to checkered.
- Racing linedrivingThe racing line is the path around a track that lets a car carry the most speed, typically outside-inside-outside through each corner.
- Reference pointsdrivingReference points are fixed landmarks like cones, curbs and boards that mark where to brake, turn in, apex and track out.
- Run groupeventA run group is a set of drivers of similar experience who share track sessions at an event, from novice to advanced.
S
- Sample ratedataSample rate is how many times per second a sensor records a reading, measured in hertz (Hz), and it sets how much detail data can show.
- SectordataA sector is one section of a lap between two timing lines, used to see exactly where on track time is gained or lost.
- Slip anglevehicleSlip angle is the difference between the direction a tire is pointed and the direction it is actually traveling while cornering.
- Slow in, fast outdrivingSlow in, fast out is the principle of entering a corner a little slower to set up an earlier, harder exit onto the next straight.
- Spin proceduresafetyThe spin procedure is what to do once a car is spinning: push both feet in, clutch and brake, so the car stops in a predictable path.
T
- Tech inspectioneventTech inspection is a pre-event safety check of your car and gear: brakes, fluids, tires, loose items, battery and helmet.
- TelemetrydataTelemetry is the recorded data from a car's sensors, such as speed, position, g-forces and engine signals, used to analyze driving.
- Threshold brakingdrivingThreshold braking is braking at the very edge of grip, just short of locking the wheels or triggering ABS, for the shortest stop.
- Throttle steeringdrivingThrottle steering is adjusting the car's cornering line with small throttle changes, which shift weight and tire load front to rear.
- Time attackeventTime attack is a timed competition where drivers set their fastest lap, usually with limited traffic, and classes are ranked by best time.
- Tire temperaturevehicleTire temperature is how hot a tire's tread runs, usually measured across inside, middle and outside to judge grip and setup.
- ToevehicleToe is the angle of the wheels seen from above: toe-in points their fronts together, toe-out points them apart.
- Track dayeventA track day is an event where drivers pay to drive their own cars on a race circuit, without racing, in organized sessions.
- Track-outdrivingTrack-out is the point on a corner's exit where the car reaches the outside edge of the track as you unwind the steering.
- Trail brakingdrivingTrail braking is easing off the brakes gradually as you turn into a corner, blending braking and cornering grip instead of releasing all at once.
- Turn-in pointdrivingThe turn-in point is where you begin steering into a corner, which largely decides where your apex and exit will be.