Scott Hantz starts the practice session off a little on the tight side of handling balance
3. The car snaps loose just after the front wheels have been turned too much, indicating a tight/loose condition.
4. Mid-turn segment times are slow, indicating a handling problem (assuming that someone is timing segments).
5. The car is not entering the turns as deep as the competition, meaning entry handling might be suspect.
6. Other cars pull away down the straightaway, which tells us that the engine performance might be off (so we can look beyond the setup to find the three tenths we are slower).
The quicker we can identify potential problems, the sooner we can fix them and fine-tune the setup.
This spotter records lap and segment times of the team's car as well as the competition.
This type of information is shared with the driver. Together, they can sort out what the problems might be and come to an agreement as to a solution. Here is a list of potential problems.
BrakesThe bias might be off, causing a loose or tight condition on entry to the corner. Solve entry problems first. The determinant is the handling. Compare floating the car in using little braking to doing an entry using much more braking to see if there is a difference in handling. If there is no difference, then the problem is probably rear steer or shock related.
ShocksIncorrect shock rates can cause entry and exit problems. The use of shocks to tune the handling is of no use if the basic mid-turn handling has not been sorted out and refined. The driver must be aware of how the car is diving and rolling under normal conditions and then be able to report when this changes, due to a possible broken shock.
I have seen cases where a driver could not tell when a right front shock had locked up and would not move. That is the most basic form of feel and feedback that is required of a driver. If you don't know when a corner of the car has quit moving, it is time for sensitivity training.
Turn spotters can sometimes see handling problems better than a spotter up on the trailer.
SteeringThe driver has the steering wheel in hand for the entire practice session and should be memorizing what he has to do with that wheel throughout the lap. If, while running at speed, he needs to do something far different than when warming up the rearend grease at slow speed, that is a clue that something is wrong.
We can tell a lot about the setup just by looking at the driver's hand position related to how much he turns the wheel. A Sprint Car driver that had to turn the wheel right to go straight (when the car was going straight ahead) could tell they had an extremely bad roll steer problem.
PowerIf we are three tenths off in lap times but right with the fastest cars in turn segment times, then we need to look to the engine for the problem, not setup. The spotter can get segment times easily. Turn segments are easier.
You only need the turn times. Compare them with other fast cars to know whether you have a setup problem or a motor problem. I've been two tenths faster per turn but three tenths slow on total lap times. Our 9:1 engine was being starved for fuel. Once we fed it more fuel, it came alive. Without knowing where the problem lay, we would have probably chased the setup, ruining the good setup we already had.