A similar situation occurs as we over-inflate the tire. The outer edges of the tire lose p
The size and cross sectional loading of the contact patch helps determine how much traction we will have for a particular tire. An added effect related to the contact patch and traction involves grooving and siping with dirt tires and will be discussed later on.
Reducing the air pressure will usually increase the size of the tire contract patch which would seem to enhance traction, but excessively low or high pressures may reduce the loading on portions of the tire so that the total loading of the tire is reduced and we end up with less available traction for that tire. There is an optimum operating air pressure for each tire that will offer maximum contact patch area and equal loading across the width of the patch.
Camber also affects the size and cross sectional loading of the contact patch. The correct camber angle compensates for the deflection of the tire sidewalls as the lateral force is applied when we turn the car. More or less camber than what would be ideal means that one side of the tire will support more load than the other and this also reduces traction.
The chemical makeup of the compound of the rubber helps to determine how much traction is available from a tire. A softer tire will provide more traction, but the maximum amount of traction that can be utilized over a long period of time concerns how the tire holds up to heat and wear.
If we could look down on the tire contact patch during cornering, we would want to see an
A tire that is a little harder may sometimes hold up better and be faster toward the end of the race when the tires have built up a lot of heat and are well worn after a number of laps. The way a softer tire grips better is in the way it conforms to the track surface irregularities. A harder tire will ride over the small dips and depressions in the asphalt or dirt while a more compliant tire will fill those areas to create more surface contact area that is riding on the track.
There is a fine line between being soft enough to fill the gaps and being too soft and causing the rubber to peel off and cause excessive wear. Racing tire companies are constantly experimenting with compounds to make the tire stick better while still maintaining a decent life span.
Angle of Attack
The amount of traction available from a tire can actually be enhanced simply by increasing its angle of attack relative to the direction of the car, but only up to a point. From straight ahead, we can turn the wheel and with each degree of angle of deviation from the direction of travel, the traction in the tire increases.
There is a point we reach where the gain is reduced and we approach the limit of attack angle that the tire can handle. Once that point is reached, going beyond causes a sudden loss of grip and traction falls off drastically. The tire will then slide across the track surface. This principle is true of all four of our tires whether they are the front or rear tires. We will provide more on this subject later.
We have talked a lot about trying to achieve a balance in your setup, but what does that mean exactly? Balance in the dynamic sense is when you have both ends of the car working together and trying to do the same thing. In a cornering situation, doing the same thing all comes down to wanting to roll to the same angle. All of what a suspension system is influenced by comes down to a simple, but comprehensive final result, a roll angle that the system is trying to end up at.
It is the matching of the desires of the front and rear suspensions that causes the correct transfer of loads during cornering. What we get out of that matching of roll angles is the best loading of all of the tires in combination that will yield the most traction, period. Here's why.