The following synoptic scheme is taken from the ACC Setups – SIMPLIFIED – For Beginners – Assetto Corsa Competizione video guide published on youtube by Nils Naujoks. Click on the image to enlarge.
Looking at the previous image, it is immediately evident that there are many possible interventions for the resolution/mitigation of oversteer or understeer problems; nevertheless they are not interchangeable with each other as each of them has repercussions on other areas of car tuning. For example, stabilizing the car by adjusting the suspension and anti-roll bars not only affects the level of mechanical grip but also greatly affects the aerodynamic balance. In the search for the ideal setup it is therefore necessary to compromise, depending on the result you want to obtain and what you are willing to sacrifice in relation to the layout of the circuit and the conditions in which you are racing. Furthermore, in order to effectively intervene on oversteer and understeer, it is necessary to identify exactly where and when the problem occurs (entry, mid or exit of corners). Therefore, use this schematic representation for a quick analysis while, for a targeted and more accurate modification of the car configuration, investigate the problem through more complete tools.
Please note:
- The negative toe angle on the rear wheels in reality makes the car unstable and is generally not contemplated under any circumstances; in simulators, on the other hand, it can result in a simple increase in oversteer.
- Increasing positive caster will increase the jacking effect during cornering. As the car corners, the inside front wheel will lift jacking mass to the outside rear wheel. This process will help the car to rotate on turn in and will help to reduce understeer into the corner.
- The variation in the amount of fuel affects the weight distribution between the front and rear. In your car, in fact, the increase in weight behind the center of gravity (due to the addition of fuel in cars with a tank at the rear) will increase oversteer due to an increase in centrifugal forces; vice versa, the reduction in weight behind the center of gravity (for example due to fuel consumption) will increase oversteer. The Porsche behaves exactly the opposite of all the other GT3s (that is to say as described above) as it has the tank positioned in front of the cockpit (see images below) and therefore in an advanced position with respect to its center of gravity (CG). Take into account the fact that the variation in the amount of fuel during the race also affects the ride height but to a small extent compared to the effects due to centrifugal forces.
- The effects of the change to the differential setting on the behavior of the car have not been described since, with the same preload value, the car can have both understeer and oversteer behavior, depending on the gear ratios inserted, low (first and second gear) or high and by the type of action on the accelerator pedal (press or coast). To see the effects of the differential preload setting on the car’s behavior, click here.
Trinacria Simracing 
