Successful drivers need to...
Successful drivers need to understand the keys they get from dataacquisition. Driver David Reutimann looks over the computer screen inhis pit cart during a practice session in 2005.
As racers, we tend to be tweakers with lots of focus placed on the racecar (modifying, adjusting, and so on). However, racing is a sport, andit's a sport because it is a contest of one person's skill againstanother's. Many people think it is the skill of building a better racecar, which does play a part, but ultimately it is a test of the driver'sracing skills.
Many racers fail to understand these specific skills or have an egoproblem that interferes with believing they can improve. Drivers whoadamantly say, "If I just had more money or a better setup, I could win"and fail to look at other possibilities typify this situation. The truthis, most wins are distributed among a few drivers at each track, andonly on rare occasions will someone else win. Why? Simply better driverskills!
Once you embrace the importance of driver skill and improving it, youtypically find bigger gains in speed than anything you can legally bolton the race car. So get comfortable, open your mind, and read on to seehow new concepts, technology, and developing specific skills can make ahuge difference in your racing results.
300 Percent Concept
Graph 1 - This is a throttle...
Graph 1 - This is a throttle graph. The scale on the left side represents thepercentage of throttle from 0 to 100 percent. The bottom scale is theelapsed time from the start/finish line as the race car completes a lap.The blue line shows how the driver controlled the throttle getting in,through the corners, and back to wide open on the straights.
An idea gaining popularity in professional racing is the "300 Percent"concept. This is actually three 100 percent pieces that work togetherand create the final performance results.
The first part of this concept is the race car's capability. Say you useregular gas, and your car is 500 pounds over minimum weight. If you raceagainst someone who is burning alcohol, has 100 more cubic inches, andis at the minimum weight, then obviously there is a big disparitybetween the cars. In this case, your car may only be 65 or 75 percent ofthe other car when it comes to performance capability. However,division/class rules tend to bring the cars closer together.
Most of the cars in a division are usually within 10 to 15 percent ofeach other (including the minor cheaters), and they get closer togetherthe farther you move up the ranks. For example, if you were to test allthe Nextel Cup cars at a place such as Martinsville, you may find theyare all within 2 or 3 percent of each other.
Another part of this concept is the driver's skill. However, unlike therace cars, drivers vary widely in skill levels. It is common at thelocal level to see a driver with an 85 or 90 percent skill levelcompeting against a 50 percent skill-level driver. In such a case, evenif the lower skilled driver had the better race car, the higher-skilleddriver would place higher on a consistent basis.
The last piece is the driver's performance on any given day. Everybodyhas good days and bad days. A death in the family, divorce, or even theflu can throw you off your game. So, on a great day, you could performat 100 percent of your skill level and on a bad day you perform at alower percentage of your given skill.
Technology to the Rescue A very basic fundamental that all engineers andscientists live by is, "You can't have improvement without measurement."This is where technology fills the bill. Race car data acquisition isnothing more than an electronic measuring system, which often isassociated with the first 100 percent of the 300 Percent concept. Thesecrets you will learn in a few moments will show how data acquisitionis crucial for improving the other 200 percent.
It is important to measure and record what the driver is doing becausewhat may feel fast in the seat isn't always fast on the stopwatch.Often, the exact opposite is true. This may sound odd, but it has beenproven hundreds of times with data acquisition. Simply evaluating whatwas measured and making conscious changes on the driver's part willresult in improvements that are nearly impossible to achieve via theseat-of-the-pants method.
Fortunately, it doesn't take an elaborate or expensive data system fordriver development. The system will, however, need a throttle sensor, asteering sensor, g-force, and vehicle speed sensors. Budget and basicdata acquisition systems typically have these sensors, but if you pickup a used system or homemade system (which are starting to flourish),make sure these sensors are included.
How to Improve Throttle Control
Graph 2 - Sometimes it is...
Graph 2 - Sometimes it is easier to interpret racing graphs when displayed in feetfrom the start/finish line rather than time. To read this graph, startat the left side, which represents the beginning of the lap. Moving tothe right at roughly 250 feet past the start/finish line, the driverlifts for the corner. At roughly 600 feet, the driver gets back on thethrottle. Following the blue line in this fashion, you know exactly whatthe driver was doing with the throttle and where he was on theracetrack.
As a driver, you may think you are in total control of your body, butmany times this is not the case. In testing, it has been found that adriver will say, "I never lifted that lap," but when you check the data,this is not the case. Sometimes there seems to be a brain-to-footdisconnect, as if the foot has a mind of its own. This is why manycrewchiefs laughingly call data systems "The Lie Detector."
To illustrate this concept, try this experiment with a chair, a piece ofpaper, and a pen. Do it as you read these instructions: Sitting in achair, straighten your right knee slightly so your foot is a few inchesoff the floor. Now, rotate your foot in a circle such that your toes arerotating in clockwise pattern.
Keep your foot rotating, write the number 6 on the paper, then quicklylook at your foot. Which direction is it rotating? Were you aware of anychange? Now, are you sure you know exactly what your foot is doing onthe throttle in the race car? Another popular phrase with crewchiefs is,"What did the data show?"
Using data acquisition, graphs can be constructed to display throttleposition all the way around the track. Watch for specific patterns whenreading (interpreting) data graphs for throttle skills. Often, thepatterns will get nicknames such as "cliffs versus roller coasters" and"pancakes versus high valleys."
Graph 3 - Specific numbers...
Graph 3 - Specific numbers for any point along a throttle graph can be displayedon your computer. Clicking anywhere along the graph, a marker line(green in this example) will appear. This software then displays thethrottle position near the top right of the screen (21.0 percent) andthe distance to the far right of the lower scale (323 feet).
An example of throttle cliffs can be seen in Graph 1. This graph showsthat the driver completely dropped the throttle in roughly 1 second whenentering Turn 1. Likewise, in Turn 3, the driver dropped the throttle inroughly 0.7 second. Especially on pavement, this tends to be less thandesirable throttle control.
Another example of undesirable throttle control is the pancake followingthe cliff. Graph 2 shows the same data but displays distance rather thantime on the bottom scale. This data shows the driver is completely offthe throttle for roughly 250 feet in each corner. Oftentimes, thepancake is a result of the throttle cliff. Suddenly dropping thethrottle upsets the car's balance, and the driver must wait longer toget back on the throttle.
Graph 3 represents a different driver with good throttle habits. You cansee the throttle pattern looks much more like a roller coaster than thecliffs in the previous two graphs. Also, notice the driver manages tokeep the throttle open between 20 and 25 percent in the middle of thecorners. These high valleys will result in more mid-turn speed than thepancakes in the previous graphs. For you sharp-eyed graph readers, youwill also notice the driver is lifting well before the start/finishline.
Graph 4 - A helpful feature...
Graph 4 - A helpful feature in data acquisition software displays information fromseveral laps at once. This graph shows the throttle control for threelaps. Each color represents a different lap.
Data acquisition helps the driver develop consistency. Graph 4 shows athrottle pattern for several laps. Sometimes, when using less throttleat the slowest point of a corner, the driver will feel the need to startapplying more throttle while exiting the turn.
However, this can end up with a wheelspin or a handling conditionrequiring the driver to modulate the pedal. As a result, the lap timessuffer (see blue line). This illustrates why it is important for thedriver to be a robot and do exactly the same thing lap after lap.
Finally, a concept popular with professional drivers is what they call"sweet spots." These are specific spots (or reference points) around theracetrack for specific throttle control (lift points, hold points, andso on). The objective is to find what points yield the best lap times.
Because the data system is measuring the distance around the racetrack,it is easy to locate different points the driver can visually identify(sign, light pole, and so on) and see what lap times or segment timesare associated with different points.
There are many other aspects of throttle control that can be improvedwith data acquisition, too. Remember, however, what feels fast in theseat is not always fast on the stopwatch.