Getting the best set-up for a racing car unlocks a huge amount of performance, particularly in a single-spec series where everybody has the same basic kit.
Different circuits require different set-ups, and ensuring your car is tuned to the demands of the track's characteristics can yield big rewards.
Think of it like playing a guitar; some songs might require a different tuning to another, and so the strings must be tightened and loosened to play the right notes.
Whether you're a racing veteran or an Esports rookie delving into the options menu for the first time, there is a multitude of different parameters you can change. With the help of former McLaren and Jordan F1 engineer Tim Wright, we explore some of those different settings and explain their effects.
How do you adjust downforce?
Adjusting the downforce levels of a car is usually a simple operation; for a single-spec car, for example, a wing may come with set levels at which the wing can be adjusted to. These generally adjust the wing angle of attack.
If we think of a neutral angle of attack as a horizontal line, steading increasing that angle of attack means that you begin to increase the overall downforce.
Adding downforce ensures that the car can navigate corners at much higher speeds, as the tyres are loaded more and generate more grip.
However, as you do so, the wing also begins to produce more drag as it displaces a greater amount of air, reducing the top speed in a straight line.
When to adjust downforce: For a circuit with long straights and high-speed corners, such as Monza, a low angle of attack is recommended, meaning you can run a shallow wing and benefit from a greater straight-line speed.
For slower circuits like Monaco, you can run the maximum amount of wing available to you to improve your cornering speeds.
Other circuits are much more of a trade-off, and you may wish to experiment with different downforce settings.
What is toe angle?
Toe angle is the angle at which, when looking down on the car from a plan view, the wheels point relative to the centreline of the car. Neutral toe means that the wheels are completely parallel to the centreline, toe out means that the front of the wheel points away from the car, while toe in means that the wheel points inwards.
Generally speaking, a race car will run with toe out at the front and toe in at the rear. This means that the front wheels are splayed outwards, whereas the rear will be pointing inwards. Front toe out not only helps to put heat into the tyre as there is a slight scrubbing effect, but can help give more grip and stability when the wheels are turned.
This is dependent on whatever Ackermann (the difference between the turning rate of the front two wheels) is designed into the car, as true Ackermann will turn the inside wheel more than the outside. This is vice versa if the car has anti Ackermann.
At the rear, toe in is run mainly because under braking the wheels tend to try and straighten, depending on the suspension geometry, therefore making a larger footprint.
How do you adjust the toe angle?
Adjusting the toe is normally achieved by shortening or lengthening the track rod. At the front this is attached to the end of the steering rack and to the upright on the outer end.
There is a rose joint on each end and sometimes there will be a right-hand and left-hand thread so that the rod can just be rotated one way or the other. At the rear, there is a similar rod attached to the chassis on the inboard end.
The popular way to measure toe is to have a line (sometimes fishing line) on each side, supported on rods attached to the front and rear of the vehicle running parallel to the centre line of the car. A measurement can then be taken from this line to the front edge of the wheel rim and then to the rear edge, the difference giving you the toe in or out.
A general figure for toe in at the rear will be 2.5mm per wheel but at the front it can be as much as 5mm toe out per wheel.
A lot of this is also dependent on how much camber is being run on each wheel.
For true Ackermann, if the outboard steering arm joint is in front of the top wishbone joint, then if you draw a line through these two points on both sides, they should converge at the centre of the rear axle.
Depending on the architecture of the front upright, it may not be possible to achieve true Ackermann and so you may end up with the lines being parallel or if the steering arm joint is behind the top wishbone joint then you can have anti Ackermann.
When to change toe angle: If you are running on an oval circuit, or a circuit with multiple corners in the same direction, putting toe out on the inside wheel and toe in on the inside wheel will help to reduce the amount of steering needed.
On the rear tyres, adding toe in will assist with braking performance, while toe out may improve acceleration at the cost of overall straight-line speed.
In the case of Mercedes' DAS system in F1, the toe angle can be controlled from within the cockpit to allow the benefit of greater toe in the corners, but reduced toe on the straights.
What does changing the ride height do?
The ride height of a car is normally measured in the middle of the car on the centre line of front and rear axles. The idea is to get the front of the car as low as possible without it touching under braking or on bumps.
The height of the rear of the car will depend on how much downforce the car will develop in normal running. In the case of a Formula One car or an LMP1 sports car, they can produce huge amounts of downforce, therefore the rear ride height tends to be reasonably high.
The most popular solution to keep the ride heights of the car at a constant level in high downforce sections of the circuit is the use of a third damper, which is linked to the normal dampers and can be adjusted with a series of spacers.
On most saloon cars, ride heights are adjusted by compressing the spring to raise the car or reducing the preload if lowering the car. On cars where the springs and dampers are operated via a pushrod and rocker, then the adjustment is made to the length of the pushrod, either by a system of shims or screwing a rose joint in or out on its thread.
When to change ride height: Ride heights are usually kept low to maximise the performance of the floor, but creating an offset between ride height at the front and rear (rake) means the diffuser has more space to allow the airflow to expand.
On bumpier circuits, raising the ride height means that the car will be less susceptible to losing downforce on the bumps. Lowering the front end also dials out understeer, and the reverse applies to counteract oversteer.
What are the tyre pressures in racing?
Tyre manufacturers will always advise teams as to the optimum pressure that their tyres will run at when hot.
In F1 this is rigorously adhered to as it is written in the regulations, but in other formulas it is fairly common to experiment with the pressures, as this can have a huge effect when it comes to qualifying or a race.
Normally a new slick tyre, depending on the compound, side wall construction and circuit length, will heat up quickly and provide maximum grip within one or two laps.
Once a tyre has been run and has had a heat cycle, the surface will become harder, therefore it takes longer to get the optimum temperature again. For a race situation, the pressures will have to be adjusted up slightly from their qualifying setting even if the tyres have been pre-heated. D
Depending on the manufacturer, tyre pressures will either be measured in imperial (psi) or metric (bar). A typical running pressure would be 2 bar (29psi) for a road car.
In F1, tyre pressures can be around 1.5bar or lower, depending on the circuit. Pirelli, F1's tyre supplier, provides every team with the required range of pressures allowed, which must be adhered to by the teams.
When to change tyre pressures: Lower tyre pressures can improve the overall contact patch with the road, improving grip, but under-inflation will mean that the handling is less responsive as the tyre carcass drags along the road and produces unnecessarily high slip angles - and hence, greater wear.
Lowering the pressures at the front creates oversteer, and lowering those at the rear generates a greater level of understeer.
Higher pressures produce less grip overall and offer a stiffer setup, but won't generate as much wear.
What are dampers and how do they work?
Dampers, or shock absorbers, to give them their proper name, are complicated pieces of engineering and come in a multitude of forms.
The makeup of a damper is a cylinder with a certain amount of oil, and a piston that tries to compress the oil or allows it to bypass with a series of small holes and shims.
To maintain pressure inside the damper, many of the manufacturers use gas in a separate cylinder where the pressure can be adjusted to suit.
As the name implies, the idea is to allow the wheels to ride bumps and kerbs efficiently without upsetting the ride of the car. However, they can also be used to help generate tyre temperatures if set properly.
The more advanced dampers might have what is called four-way adjustments, so you have low speed and high-speed bump and low speed and high-speed rebound. This relates to the speed of the damper shaft and determines how it reacts to a series of bumps.
Some sophisticated dampers have a 'blow off valve' that allows the pressure to be dumped temporarily in the case of a heavy kerb strike. The adjustment of each feature is normally achieved by turning an internal shaft that is connected to the piston and basically opens or closes a series of ports.
The more closed the port becomes, the harder it will be for the oil to pass by the piston. This can also be achieved by using a stack of very thin shims that deflect under pressure.
In some racing categories like F1, cars use torsion bars (above) rather than shock-damper systems to control the ride. When the suspension assembly rises in response to a kerb or a bump, the pushrod or pullrod puts the torsion bar under a twisting motion.
Different sizes and arrangements of torsion bars provide different degrees of resistance.
When to change spring rates: Reducing spring stiffness at the front relative to the rear will reduce understeer, while the opposite applies to reduce oversteer.
Softening the springs at the rear also allows the car to put more power through the wheels, but doing so too much increases oversteer and makes the back of the car difficult to control.
Engineers take all of those factors, along with the demands of the circuit, into account to dial in the right handling characteristics.
What are camber angles?
Camber is the inclination of the wheel assembly when looking at it from the front or rear view.
Positive camber is when the top of the tyre is leaning out compared with the lower part and negative camber is obviously the opposite.
It was quite popular on latter day race cars that ran skinny tyres and large suspension movements to run with positive camber, especially on the rear, as when the car accelerated and the rear end sat down, the contact patch would be flatter.
Modern day race cars only run with negative camber, as seen above, as tyres are much fatter and have stiff side walls that can control the tread. Again, the tyre manufacturers will always advise the maximum amount of camber their tyres will withstand from a loading point of view.
Running negative camber means that, when a car rolls in response to a corner, the outside wheel has a greater contact patch to ensure the car remains stable.
However, camber can bring stability to a setup and in conjunction with toe settings can have a big influence on grip.
A lot can be learned from inspecting a tyre once it has been run, as it is obvious where the tyre has spent most of its time in contact with the track.
Slick tyres have wear indentations in the surface which allow you to see how much the camber is wearing the tyre and you can adjust the camber to get more of a contact surface.
Also, there is an effect called 'graining' on the surface of a tyre that indicates that not enough heat is being generated and the surface of the tyre starts to be rolled or pushed towards the outside of the tyre. Camber and toe settings can be used to improve this.
When to change camber: Generally speaking, a racing car should only use negative camber - and the rear wheels use less camber than the fronts.
Using a camber setting that counteracts the roll of the car - so that the outside wheel has the largest contact patch possible - in corners is ideal, but too much camber means the inside of the tyre can wear faster than the outside.
The amount of negative camber can also be reduced if the car has too much oversteer.
What is bump and rebound?
The most basic racing dampers will have several adjustments for compression, called 'bump' and for extension, called 'rebound'.
Bump is when the piston travels down the cylinder and rebound is when it tries to return.
The softer you can run the compression side means that the car will be better on the bumps etc but may not control the roll of the car very well.
This is where a setup needs to take into consideration the relationship between using an anti-roll bar in conjunction with damping to achieve a good result.
When to change bump and rebound: Dampers are also used to control the attitude of the car, so that it doesn't pitch too much under braking.
To achieve this either a stiffer compression is used on the front, or a stiffer rebound at the rear will stop the rear of the car rising, but the down side is the effect this has on traction and causing understeer, so it becomes a delicate balancing act for the engineer to work out the best settings.
A stiffer compression setting at the front will also reduce understeer.
What is brake bias and how do you change it?
Brake bias is a simple device controlled by the driver. Running laterally through the brake pedal, just above the pivot point, is an adjustable bar, or balance bar to give it a proper name.
One side of the bar is attached to the front master cylinder, by a clevis, and the other side attached to the rear master cylinder. Normally there is a cable attached to the end of the balance bar and by turning the cable from inside the cockpit, the driver can move the bar left to right or right to left, depending on whether they want the bias to go to the front brakes or the rear brakes.
When the driver pushes the brake pedal the balance bar will pivot and put more pressure on one of the master cylinders.
On most modern racing cars, the bias is set around 58% to the front brakes and the driver can then adjust the balance depending on tyre wear or fuel load. With hybrid cars such as F1 this is slightly more complicated as the brake energy is part of the storage system.
When to change brake bias: Looking at a circuit holistically, shifting the brake bias to minimise the overall locking under braking is key, but some corners may provide different challenges to others.
Too much locking at the front requires a shift of brake bias rearwards, while the opposite applies in the event that the rear locks up too much.
What is an anti-roll bar?
Anti-roll bars (or anti-sway bars as the Americans call them) are designed to do exactly as it says: limit the amount of body roll in the car.
There are many different designs of mechanical ARBs, but usually they are a tube or solid bar mounted laterally across the car and attached to the front and rear suspension systems by an adjustable link.
The bars will have an arm on each end at 90 degrees to the bar, so that when the car rolls, the bar is twisted and resists the movement. The bar is therefore a highly stressed item. The arms may have a series of holes along their length so that they change the angular deflection of the bar.
Another way of changing the forces put into the bar is for the arms to be a blade that can be turned. With this system it is possible for the driver to adjust the blades by way of a cable inside the cockpit.
Anti-roll bars are also a device with which to balance the car.
When to change ARB settings: If the driver is complaining about understeer you can soften the effect of the front bar. If they are complaining of oversteer or bad traction, then you can soften the rear bar to let the car roll more into the corner.
Quite often when running in the wet, disconnecting the rear anti-roll bar altogether can help as this allows the suspension to move more freely and therefore there is greater tyre contact as the car rolls.
What is a caster angle?
The caster angle is the difference between the vertical axis of the suspension and the axis at which the steering pivots. It's perhaps easiest to visualise on a motorbike, where the front forks are often inclined at an angle compared to a vertical line drawn across the front wheel.
On a Formula 1 car, the steering pivot axis is the line joining the pivot points on the upper and lower wishbones.
Generally speaking, the upper wishbone's mounting point trails further back down the car compared to the lower wishbone, and this creates positive caster. This is commonly used as it provides the driver with clear feedback, and generates its own self-aligning torque due to the positioning of the trail behind the steering axis.
This also amplifies the effect of camber in the corners to boost the overall grip.
Negative caster is rarely used and, although it lends itself to more easy steering on a small scale, it has none of the bonuses experienced when setting up a car with positive caster.
Caster is usually built into the car's suspension system, but over recent seasons teams have experimented with the positions of mounting points to explore the effects of caster.