Taking and recording turn...
Taking and recording turn segment times will allow you to directly compare your performance in the turns to your competitors' times. Turn segment evaluation tells us when we are set up correctly better than lap times that include straightaway acceleration.
The First Set of Runs
The driver should initially make several slow five-lap circuits and then five faster circuits runs to "shake down" the car the first time out. This establishes that the brakes work as expected, the wheels are on tight, the air will stay in the tires, there are no water or oil leaks, and the transmission and rearend lubricants will be brought up to temperature. We should do two more five-lap runs following the initial outing before we'll be able to get meaningful tire temperatures.
After each of these runs, record the tire pressures and/or temperatures, tire sizes, engine water and oil temperatures, and number of laps run in each session. Make hard copy records of the data in addition to digital records (stored in the tire temperature/pressure box or a computer). It's fine to have digital records, but we all know how easy it is to loose digital information. Doing both is the best way.
Once the driver is confident that the car is sound, longer and faster runs can be done. As you make your next series of runs, try to have the driver stay out at least 10 laps so that the tire temperatures will be sufficient to show how they're working. Unless the car has a serious handling problem, this shouldn't be an issue. View the car from a high vantage point and note how the car looks and where the driver's hands are positioned and how far the wheels are turned while in the middle of the turns.
Testing also includes driver...
Testing also includes driver orientation to a new and different racetrack. In this aerial view of Concord, we see a strange configuration for a track that has a smaller radius in Turn 1, a reduction in banking going uphill toward Turn 2, then a dip and flatter kink going toward the backstretch. Then Turn 3 is tight with a widening radius off Turn 4. The various changes in banking cause loss in traction if not dealt with correctly with the shock settings.
Now is the time to evaluate the tire cambers, pressures, and overall handling balance. Make quick adjustments to the front tire cambers and all four tire pressures if the temperatures dictate. The handling can't be properly evaluated if these issues aren't corrected right away. Don't make chassis adjustments until the tire issues have been corrected.
Excess driver steering input at mid-turn, inability to keep the car low in the turns, and a car that snaps loose coming up off the turns are all indications of a tight setup. Have the driver run the turns at a speed lower than normal and note the position of his/her hands. Then, once the car is up to speed, the driver should again note where his hands are and if the steering is significantly different, the car is either tight or loose.
Record the driver comments as well as crew comments as to the handling and engine performance. If the car is not neutral, now is the time to make changes to improve the handling while working to maintain a balanced setup.
There's a difference between hand-ling balance and dynamic balance. The car is neutral when it's neither tight nor loose. We can easily adjust most cars so that they will be neutral. This may make the car faster, but it's not our primary goal. We need for the car to be both neutral in hand-ling and balanced in how the front suspension and rear suspension are working. When both ends of the car are working together, we'll truly have a balanced car that will be both fast and more importantly, consistent.
First We must always evaluate and correct the mid-turn performance first. To balance the car at this "steady state" point on the track will also help to balance it on entry and exit. Steady state is defined as a condition where the car is neither accelerating nor decelerating. So the dynamic effects of longitudinal weight transfer from braking or motoring off the corner aren't affecting our evaluation at this point in the test.
Before our test begins, we...
Before our test begins, we all need to meet and discuss how the test will proceed. If everyone is on the same page, the test runs smoothly and we're able to gather data that will lead to a better setup.
We can interpret the balance of the car by evaluating the tire temperatures. The easiest way to make a car handle neutral is to adjust the crossweight percent. Crossweight is the percent of the total weight of the car that is supported by the right-front and left-rear tires as read on the scales. Lowering the RF and LR corners and at the same time raising the LF and RR corners will reduce the crossweight percent and loosen the car. We always want to make changes to all four corners to effect a change in the crossweight.