TECH TUESDAY - THE WHEELS
Tyres are such an integral part of a car that it is easy to forget just how important their settings actually are in terms of influencing driving behaviour. In the following article, you will learn more about the different adjustments and their effects.
Of course, our racing simulators do not have physical tyres that can be modified, adjustments can however be made in the game. These changes can have a big impact on driving behaviour. In this article we will have look at them in a little more detail.
Racing Tyre vs. Road Tyre
The racing tyre significantly differs from the normal road tyre. Even just the tyre profile alone shows striking differences. While the road tyre can be used in all weather conditions, the racing tyre has been specifically optimised for one purpose – to reach the highest possible speeds without losing grip. This requires different tyres for different weather conditions. The tyre for dry conditions, also known as the «slick tyre», has no tread pattern. Its advantage is that the contact area between the tyre and the track is utilized to the maximum. When the rubber on the tyre is heated, it begins to stick. This results in more grip in curves than would be possible with a road tyre.
However, more than just the right tyre pattern is required in order to extract the best performance possible out of the tyres. Several other components are just as crucial, e.g. the tyre pressure and wheel settings.
The pressure of a racing tyre is usually set lower than in road tyres. As higher temperatures are achieved on the track than on the road, the tyre pressure therefore increases more quickly. Also, less air pressure generates more contact between tyre and track. The difference in tyre pressure before and after a race can be up to 1 bar.
But what happens if the tyre pressure is set too low or too high?
Generally, tyres with less air pressure have a larger surface area subject to stress and offer the driver more grip in turns. At the same time, however, the vehicle also becomes sluggish under high loads, as is for example exerted on the brakes. Higher air pressure in the tyres, on the other hand, leads to higher speeds on straights and increases stability when braking or accelerating. Therefore, the consequence of tyre pressure that is either to high or to low is the same: the braking distance is increased. Too little air pressure will also wear out the tyre more quickly, while too much air pressure will reduce cornering stability.
But it is not only the tyre itself that is crucial, but also its position on the car. This is regulated by the toe and camber.
The camber determines the degree of inclination of the tyre towards the vehicle. A negative value indicates that the upper part of the tyre is inclined towards the vehicle, while a positive value indicates inclination away from the vehicle. In Formula 1, cars are driven with a negative tyre camber. That means that the inside of the tyre heats up more on straights, but the car has more contact surface in corners due to strong weight distribution, thus providing more grip. The disadvantage is that the car is more unstable under braking. The more the wheels tilt away from the car (i.e. the greater the camber value), the greater the reversing effect. However, both extremes lead to high tyre wear.
The track determines the position of the front edge of the tyre in relation to the vehicle. When the tyre is turned towards the vehicle, this is called toe-in. When turned away, it is called toe-out. Formula 1 cars are adjusted with toe-in on the front axle and toe-out on the rear axle. More toe-in has the advantage that it is easier to turn in. However, it also leads the vehicle to become more unstable in handling. More toe-out makes the vehicle more stable but at the same time less sensitive.
An Interplay of Components
As you can see, all these components put together have an influence on how the tyre wears out. It is important to bring the tyre into an optimum temperature range of 80 – 100° C. Temperatures below or above will lead to a loss of grip in the corners of the circuit.