Glossary
Racing setup terms, explained with numbers
Every term includes a definition, typical values by discipline, how to measure or adjust it and the questions racers actually ask. Written for club racers, engineers and sim racers alike.
Ackermann steering
Ackermann geometry makes the inside front wheel steer more than the outside. Learn what 100%, parallel and anti-Ackermann mean and how race cars use them.
Aero balance
Aero balance is the share of total downforce on the front axle. Learn how wing angle, rake and ride height move it and what percentage race cars target.
Anti-roll bar
An anti-roll bar links left and right wheels to resist body roll. Learn how bar stiffness shifts understeer/oversteer balance and how to adjust blade and arm settings.
Brake bias
Brake bias is the share of braking force on the front axle. Learn why it must exceed the weight distribution, typical percentages and how to tune it by lock-up behaviour.
Bump steer
Bump steer is unwanted toe change as the suspension moves. Learn how to measure it with a bump steer gauge and how to correct it with tie rod height shims.
Camber
Camber is the tilt of the wheel from vertical, measured in degrees. Learn typical race settings, how to read it from tyre temperatures and how to adjust it.
Caster
Caster is the forward or rearward tilt of the steering axis. More positive caster adds camber gain in corners and steering feel. Typical race settings inside.
Centre of gravity height
CG height drives total lateral load transfer. Learn the formula, typical values for race cars and how to measure it by raising one end of the car on scales.
Corner weights
Corner weighting balances the load on each tyre. Learn how to calculate cross weight (wedge), typical targets for circuit and oval cars and how to adjust it.
Damper (shock absorber) settings
Dampers control how fast the suspension moves, not how far. Learn what bump and rebound do, the low-speed vs high-speed split and how to tune them.
Differential setup
A limited-slip differential controls how much the driven wheels can rotate at different speeds. Learn what preload, ramp angles and locking percentages do to handling.
Dual spring rate
Two springs in series produce a combined rate lower than either spring. Formula: 1/k = 1/k1 + 1/k2. Learn how tender and helper springs change the curve.
Gear ratio and final drive
Learn how gearbox ratios and the final drive combine into an overall ratio, how to calculate speed per gear from RPM and tyre diameter, and how to pick ratios for a track.
Motion ratio
Motion ratio is spring or damper travel divided by wheel travel. Learn how to measure it and how it converts spring rate to wheel rate.
Oversteer
Oversteer is when the rear tyres lose grip before the fronts and the car rotates more than intended. Learn to separate entry, mid-corner and power oversteer and how setup cures each.
Rake
Rake is the difference between front and rear ride height. Learn how rake shifts aero balance and mechanical balance, and typical values by car type.
Ride frequency
Ride frequency is the natural bounce frequency of the sprung mass on its springs, in Hz. Learn the formula, typical targets and how it guides spring choice.
Ride height
Ride height is the gap between the ground and a reference point on the chassis. Learn how to measure it consistently and how it affects aero, roll centres and grip.
Roll centre
The roll centre is the point the sprung mass rolls about at each axle. Learn how its height relative to the centre of gravity sets roll moment and jacking forces.
Scrub radius
Scrub radius is the distance between the steering axis and the tyre centreline at the ground. Learn how wheel offset changes it and what it does to steering feel and stability.
Shock velocity histogram
A shock velocity histogram shows how much time each damper spends at each shaft speed. Learn what a good shape looks like and how to use it for damper tuning.
Spring rate
Spring rate is the force needed to compress a spring by one unit of length. Learn lb/in to N/mm conversion, how it sets natural frequency, and typical race values.
Stagger
Stagger is the circumference difference between right and left tyres on the same axle. Learn how it turns an oval car, typical values and how to adjust it with pressure.
Toe
Toe is the angle of the wheels when viewed from above. Toe-out sharpens turn-in, toe-in adds stability. Typical race settings and how to measure them.
Tyre pressure
Tyre pressure sets contact patch shape, temperature build-up and sidewall stiffness. Learn hot target pressures, cold-to-hot gain and how to adjust per corner.
Tyre temperature spread
Tyre temperature spread across inner, middle and outer tread tells you whether camber and pressure are right. Learn the targets and what each pattern means.
Understeer
Understeer is when the front tyres lose grip before the rears and the car runs wide. Learn how to diagnose entry, mid-corner and exit understeer and which setup changes cure each.
Weight transfer
Load transfer moves weight between tyres under braking, cornering and acceleration. Learn the formula, what setup can and cannot change, and how it drives balance.
Wheel rate
Wheel rate is the effective spring stiffness at the tyre contact patch. Formula: spring rate × motion ratio squared. Worked example and why it matters.