ExclusiveTech Articles

Universal Tech – You Have the Right to Ask Questions

First, we need to define Critical Thinking from a higher altitude. We need a working definition that will help crystalize just what Critical Thinking is and how we should apply this process to racing. It is simply the process of actively applying information as a guide to action. Using and analyzing data to assist in making decisions. In our case, its using empirical data to make decisions or guide adjustments and actions on the tuning of a racecar. As opposed to relying solely on memory or guess work.
We need to understand that the process of Critical Thinking is a key component of the tuning process. We should avoid making “kitchen sink” decisions as it applies to our race car. Making changes haphazardly is not tuning, it is guessing. Yes, there may be times when this “may” be acceptable, but it is not, nor should it be the norm. Guess work leads to variation and more often than not, poor results and unrepeatable, unreliable setups. Throwing everything at the car makes for good TV but, in the real world, it is just not a good thing.
The process of Critical Thinking has some steps we can define that will help you or guide you to making Critical Thinking a seamless process. Let’s work through a real problem one that I was involved in several years ago. The problem was that a racer was having a very difficult time with rolling starts and restarts during the race.

Identification of a problem or a condition that is causing performance issues
The problem was identified as poor restarts. At this point we are not looking for solutions, we need to define the problem. In this case we were getting poor restarts. The team had lot of potential solutions but no data to support the problem. Identification of the problem is the first step.

Brain storm potential causes of the problem is the next step. Capture a variety of potential causes of the problem. Everybody on the team had a solution to what they thought was the problem but no actionable plan for solution. Here is a list of potential causes:
Excessive wheel spin on restarts was resulting in the poor restarts.
The issue is being caused by an overzealous driver. While this is or was a possibility, I have always been cautious to just blame the person in a process for the problem. It may in fact be the source of a problem, but we need to work to from a solution(s). Always pointing to the driver always being the source of the problem is probably the least clever method to fix a problem.
Tires are worn to the point where they are not providing sufficient grip. Our observation did note that the driver had less issues with starting the race than subsequent restarts during the race.
The engine has too much power and is upsetting the chassis.
The suspension is not able to handle the torque generated at the point of the restart.
There is an issue or issues with the car, mechanical reasons that are causing this problem.
The restarts are too slow and the sudden application of power is upsetting the chassis and the car is not transferring sufficient load to the rear of the car.
The gear ratio in the transmission is too low for the restarts.
The track does not have enough grip for the car to hook up to the track.
Restarts take place at a point on the track where the car is still turning slightly.
After we have developed a series of potential causes we need to review and analyze the potential causes of our poor restarts. Some questions need to be asked and answered at this point. Do we have any data? At this point very little.

Gather Data
Do we have any data that supports our restart history? Again, we need to define data. Data come in two basic types – Qualitative or Quantitative. Qualitive is data that is non-numerical. From a racing perspective, it may be a tire is as out of round or a spring that is bent. Quantitative data is expressed as a number, weight, force or lap time, are all expressed as a number. Both of this type of data should be in your notebook. You do you have a notebook, right? Even if you do not have a notebook, you have some data. Observation is still data; the problem is that many times observation is not always something that has 100% accurate or accurately recallable. Difficulty with recalling data really is the issue.
It is at this point I re-tell a comment that a lawyer friend of mine once told me. “He loves eye witnesses, as they are the most unreliable witnesses”. They often have a hard time recalling events that happened right in front of them. Often, they are not able to recall events at the scene and more often than not the more time that passed the details become more and more unclear. So, relying on memory is sometimes less than accurate. That is why we keep written records. (I have covered the importance of keeping written records many times in the past, we don’t need a rehash at this time.)
It is becoming more and more and common that many teams have data recorders on the car that will help us to see what is going on while the car is on the track. Some of the more advanced data recorders keep track of wheel speed and MPH, which is not always the same. Many times, data for speed in MPH is recorded of the right front wheel and not the rear wheels as tire spin can cause errors in the data set. It is entirely possible that the rear tires are traveling at a greater rate of speed than the car is traveling. Slip is entirely possible, if the rear tires are spinning the actual MPH will be slower than that of the rear tires. In fact, depending on the stagger, you may have in the car both of the rear tires will be traveling at a different speed. This can cause a loose condition due to one tire being dragged due to excessive stagger. If you have a throttle position sensor you can monitor when and how far, the driver is moving the throttle at any given time. I have been in many test sessions where the driver was telling us he was going into the corners without lifting but the throttle position sensor was telling a different story. Not that the driver was consciously lying, but he was lifting and did not even realize it was happening. Again, eye witnesses can be less that accurate.

Data Reduction, Sorting, Analysis, Review and Comparison
The act of reviewing the data and putting it into a form that you can easily review at a later date is key to the Critical Thinking process. Just having random columns of numbers without some form of rigor to help you use the data is just as useful as no notes at all. Unless, you are good at gleaning information from a column of numbers. Data arranged in charts and graphs or simple text form in a logical presentation so you can glean the message is always more helpful. The point is that the data needs to be in a form that it is understandable and recallable. Remember if the data is in a form that does not make sense the data will not be helping you and the team.
You should be able to define the car and how it is adjusted, what was on the car from an equipment perspective, this includes the engine for example, how many laps are on it, general condition, engine setup. This is all useful data. Tires are another thing that you should be able to define numerically, from how old they are the date of manufacture, date of purchase and number of laps on each tire. Your data should be this exacting. If you are using new tires each race this should be an easy data point to collect. If you run multiple races on your tires; it will require a better more exacting set of records. No matter what your tire options you should be measuring tire condition (s) continuously.

Develop Some Options for Potential Fixes to the Problem
You have data, you have reviewed the data now it is time to start developing some solutions based on the gathered data. You may have determined based on your data, that excessive wheel spin is a significant contributor to your poor restart performance. So how did we come to this realization. First it may have been just observing the car and watching your car as judged by other cars on the track. You have through a process of elimination and subsequent testing, found that the tires were in good condition and were capable of getting good traction and the condition of the track is or was not a contributing factor as your restarts were poor on both dry and tacky conditions, based on our data. The data is pointing towards a reduction in wheel spin would improve your restarts. Again, what can we do to minimize wheel spin? We could coach the driver to be less aggressive on the starts and make every effort to gently apply the throttle. We could vary our air pressures to possibly develop more grip but that may impact the cars performance over the longer term.
We could do some engine adjustments to kill some low-end power but this may also have some impact on the overall power of the engine and we are not willing to take power away. We could look at suspension and chassis weights and tire pressures to optimize these factors.

Which Solutions Worked and Which Did Not
The engine having to much power was ruled out as was the tires losing grip. Track surface played a bit into the data as the track changed through-out the race. Tire pressures were spot on and after many debriefs with our driver post heats, mains and review of the nights racing immeately yielded a good nugget of information. Our driver was telling us that the throttle pedal was difficult to move through the full range of travel. And, that the total amount of travel of the gas pedal was very short. From his perspective the throttle was more of a on and off switch than a smooth acting pedal. This caused the engine to spool up quickly and consequently upset the chassis and the result was wheel spin. The pedal travel coupled with the mental pressure of the nights racing and subsequent level of concentration made the car more difficult to drive. The input from the driver, the data we received from the driver, helped in making the next decision. We needed to adjust the pedal to have a greater amount of travel and remove any potential mechanical (binding) issues with the pedal. Subsequent inspection revealed that the throw on the gas pedal did more closely resembled a switch, while there were no mechanical binds the amount of force required to move the pedal through its full range of travel was very low. All of our other data did not really point to why we were getting excessive wheel spin, they were potential causes, but the data we had gathered, although good information, was not really characterizing the cars problem.

Improve the Solution(s)
The next steps were to improve the pedal feel for the driver. We changed the linkage to yield a greater amount of pedal travel than the car previously had and we changed the throttle return spring to a stronger spring, these changes gave the driver a greater level of feel and subsequently a greater level of control. The engine was not going from pace lap speeds to full throttle in an instant. These changes gave the driver a greater range of motion to help him control the amount of throttle the car was given based on the current needs. This single change made a huge difference in restarts and the driver had an easier time controlling the car into and out of the corners. While this seems like a very simple change the impact to the car’s performance was significant. During our use of Critical Thinking the team started to ask more and better questions. They learned that asking the right questions in a learning process and developing better processes really could help them make the car as fast as possible.
Critical Thinking is not magic, it is not going to solve all of your problems. But it will help you to drive down to solutions to your problems in a more expedient way. The gathering and use of data is critical to making your racecar as competitive as possible. It really is that simple.