SCCA
Sports Car Club Of America, a sanctioning body.

SECOND REACTION
The rebound of the chassis toward the inside springs after a slide stops. Must be countered by the Recovery phase of CPR to prevent a hook-slide.

SEGMENT TIME
The time it takes to drive from point to point on a section of racetrack.

SEQUENTIAL TRANSMISSION
A fast shifting, constant-mesh, motorcycle-type gearbox that shifts directly to each gear without going through neutral.

SHAVED TIRES
Street tires can be shaved so that their tread depth is greatly reduced to make them race-ready. This prevents the tire from overheating and provides more traction.

SIGHT PICTURE
A visual template that drivers use to locate themselves precisely on the racetrack. After using The Procedure to Find the Line, a driver takes a visual snapshot of each turn. He/she now will know where to be in every turn and be able to catch mistakes early.

SLIP ANGLE
While cornering, there is a difference between the direction that the centerline of the wheel is pointing and the direction that the tire is traveling. This difference is measured in degrees and referred to as slip angle. Tires have a range of slip angles where they deliver their maximum level of cornering traction.

SLIPSTREAM
The area of clean air behind a moving car. Also defined as following closely in the draft behind other cars.

SLOW HANDS
The opposite of “fast hands.”

STACK-UP
At the start of the race, the tendency for all the cars to arrive in the first turn at the same time.

STEERING LOCK
The maximum degree of steering input available on a car.

STRAIGHT (“straight-away”)
Self-explanatory, except that if the portion of the circuit can be driven as fast as the car can go, the road doesn`t necessarily have to be perfectly straight to be considered part of the straight-away.

SWAYBAR/ANTI-ROLL BAR
An adjustable suspension device at one or both ends of a car that limits weight transfer. Some are cockpit actuated. Sway-bars control the rate of chassis roll relative to the suspension.

SWEEPER
A fast, “sweeping” corner.