If you can't remember how the car handled at specific points of the track, you won't be able to improve its performance.
If your car has adjustable shocks, antiroll bars, springs, aerodynamics or other chassis components, then just as with tire data, the settings used and their impact on the car's handling is critical information. Record the settings of each of these components at the beginning of every session.
When you come in from the session, immediately (second only to taking tire data) write down the handling characteristics of the car. Was it understeering in turns 3 & 7, was it oversteering exiting turn 6? A little or a lot? During the first half of the turn, or the second half? Additional items you should note include corner entry or exit lines you believe you're not doing well or consistently, and any other information about either the car's or your performance that may help you do better the next time.
As you can tell from even the professional ranks of racing, there is no sure formula to tell you how to adjust the car to have it handling perfectly in every corner. If the car tends to oversteer through several turns, the cause of this could be several things. Getting rid of it might require adjustments to the rear suspension, or maybe even the front suspension. The more detailed the information you can remember and write down, the greater chance you have for determining the best adjustment path. Often it is a trial and error process where you try several solutions and see which one was best.
The articles in the Handling section covers in detail the purpose of all suspension major components, their impact on handling, and a guide for how to go about making adjustments.
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