COT brings return of driving after years of just steering

The COT has brought a refocused reliance on suspension versus aerodynamics and drivers are still adjusting. Bill Borden explains the nuances of tight, loose, balanced and neutral.

Updated: March 27, 2008, 2:04 PM ET
By Bill Borden | Special to ESPN.com

Since the start of this season, we have been hearing the drivers complaining that their cars are not handling the way they want them to during a race. Since the Car of Tomorrow became "the" race car for NASCAR's Sprint Cup series, the drivers are having to learn how to drive a race car like their predecessors did -- by the feel in their hands and seat.

[+] EnlargeJamie McMurray and Paul Menard
John Harrelson/Getty Images for NASCARJamie McMurray, top left, experiences a "pucker moment" at Bristol.
Today's drivers had gotten used to steering (versus driving) what had become the equivalent of a large and brightly decorated "vacuum cleaner" because the old car sucked down to the track with the aerodynamic packages the engineers had developed. The drivers had become just another mechanical part of the engineers' equation when setting up the car. Wind him up, tell him what to do or not to do and send him out to play. The drivers accepted this concept because it meant the cars practically drove themselves and the drivers did not have to think or over-extend themselves to collect their multimillion-dollar paychecks. Sure they were just as talented and just as brave as their predecessors but, just like their predecessors, most of them can be a tad lazy.

However, NASCAR put the "driver" back in the driver's seat with the COT. That is why you are hearing more complaints about ill-handling race cars this year over last year. There is a refocused reliance on suspension versus aerodynamics plus much stiffer rules restrictions so the period of adjustment is not going as well for some teams as it is for others. If you would have bet me that it would be five races into this season before a Chevrolet won and that Rick Hendrick's four teams would be "O-fer" with just one of them in the top 10 in points then you would have made a tidy little sum off me.

Hendrick was strongly opposed to the introduction of the COT last year, which made no sense at the time because his teams dominated the COT races last year by winning more than half of them. But this year they can't seem to find their way to Victory Lane in a points race, which might indicate he knew what he was complaining about.

My personal theory is that the reasons for Hendrick's lack of success so far this year are twofold. One is that he focused or diverted too many of his resources to the 88 team trying to make Dale Earnhardt Jr. successful early on and the other is that Hendrick's competitors have erased the advantage that his teams had gained through early research and testing with the COT last year. You could also add in the old "luck" factor for a third reason.

I like the fact NASCAR has reduced the number of math and physics equations that the engineers can apply to a car by tightening the rules more, which has increased the number of times the driver has to correct the steering wheel during a lap. He now has to drive the car and react to its nuances quickly and accurately to be successful just like David, Richard, Cale, Bobby and their contemporaries had to do. (If you don't know who David, Richard, Cale and Bobby are then you need to read some of the NASCAR record books.)

I recall a young driver asking Richard Petty how to tell just how fast he should drive into a corner. Petty's terse reply was "cheeks will tell you." After making a couple of laps where he half scared himself to death, the young driver figured out which set of cheeks Petty was referencing. Petty's punch line was "How much of that seat can you grab with 'em?" That was Petty's interpretation of the "pucker factor."

The team now has to concentrate more on suspensions and getting the car more balanced or neutral to be more competitive. So just what does "balanced" or "neutral" mean in a race car? In a street car it means the weight is distributed equally to its four wheels but "balanced" in a race car factors in all the dynamic variables that the car will experience as it moves through the turns and straights while braking and accelerating.

Race cars are driven as close to the edge of maximum performance as possible where, by contrast, we seldom exceed 50 percent of a street car's capacity. Therein lies the difference. A "balanced" race car may look like it has the left front wheel sitting in a hole versus sitting flat and level like your street car. The reason for that is found in the laws of physics and has to do with inertial forces, centrifugal forces, centripetal forces, roll centers, centers of gravity and dynamic load transfers, etc. along with a variety of other physics terms, definitions and laws.

For the purposes of discussion here, This article relates to cars being driven on an oval track where they are constantly turning left.

First let's define "loose" or "oversteer." What you call it depends upon whether you drink beer or wine and where your tattoo is located. For us beer drinkers loose means that the front tires are achieving more grip or adhesion to the track than the rear tires which makes the rear end of the car want to slide out when entering or exiting a turn. For you wine drinkers -- you know, the ones who hold their little pinkie out when they drink tea -- it means the same thing but you call it oversteer.

So what does "push," "tight" and "understeer" mean? Again, for us beer drinkers; push and tight means that the rear tires are achieving more grip or adhesion to the track than the front tires so the car does not want to turn when steering is applied. "Understeer" means the same thing for you winos.

The late Neil Bonnett's succinct explanation of loose and push was that if you are loose your rear end will hit the wall first, if you are pushing then the nose will hit the wall first.

Now we come to "balanced" or "neutral". You would think that the simplistic definition would be that the car has an even or equal weight distribution. But, of course, you would be wrong. Remember, we are dealing with static and dynamic weights here. The "static" weight of the car will be very different from the dynamic weight of the car as it transitions through the corner and experiences braking, turning and acceleration. For example, as the driver enters onto a turn he will lift off the accelerator, apply braking and begin turning the wheel. Each of those actions impacts the dynamic weight of the car -- and thus the load transfer -- in a different manner and changes the balance of the car.

Applying the brake shifts weight from the back of the car to the front in a direct line and lowers the front end, which creates "dip" (for you winos) or "dive" (for you beer lovers). Turning the wheel while entering the corner creates side load (centripetal, centrifugal, inertial and lateral forces) which alters the balance as well. All of these actions want to lift the rear of the car and unload the rear tires and suspension, thus creating a rear loose imbalance just when the balance of the car is most critical to achieve optimum handling. This is also known as the "pucker moment" or "pucker factor" for the driver.

As a former spotter, I can tell you that it is not a good time to be keying the radio and trying to talk to the driver. They tend to get a bit testy when their concentration is interrupted during that "moment." Kyle Petty once questioned my parentage and sexual preferences when I did that to him at Michigan years ago.

[+] EnlargeKyle Busch
Todd Warshaw/Getty Images for NASCARKyle Busch, front, seems to have gotten a better grasp of driving the COT so far this season.
So balancing the car is a very delicate endeavor. The track changes during the race, the tires wear, the fuel load burns off and you cannot always run your preferred line. It is therefore nearly impossible to achieve a perfectly balanced race car which is why the teams pursued creating more aerodynamic downforce over working more on the suspension setups in the old car. They had just about maxed out all of the tricks they could come up with when it came to suspensions so they turned to aerodynamics to make the cars stick more in the corners and therefore achieve balance more easily.

The aerodynamic manipulation is one reason the old cars looked like they were being reflected (from a head-on view) in one of those distorting mirrors at the old Circus Fun House you frequented as a kid. Body panels were warped and manipulated to gain added downforce while the suspensions were designed to lock down (coil binding) once the car was up to speed. This blocked the air flow from going under the car and redirected it to flow up and over the roof and back to the rear spoiler, which helped to force the rear end down more and achieve a better balance.

NASCAR didn't like that concept. After all, they come from a long line of beer drinkers. Aerodynamic downforce manipulation is more in tune with the wine and cheese crowd.

Which raises the question, do you think Earnhardt Jr. is a beer drinker? How about Kasey Kahne? Tony Stewart? Dario Franchitti? How about Aric Almirola? His name even sounds like an exotic drink! That might be a good guessing game while sitting around a campfire in the infield at the next Talladega race. Anyway, back to balance.

When setting up a race car for an oval track you have to factor in a great number of variances and work to reach a compromise that will balance the car. Hopefully you have it adjusted to where you can make minor "tweaks" to it during the race to chase the track and the changing conditions of the race. Minor tweaks would be: air pressure adjustments, adding spring rubbers or adding or taking out rounds on the track bar, etc. If you have to get any more radical than that then you've missed the setup.

Chad Knaus, crew chief with the No. 48 team, has become a master at that technique. But you have to be in the ballpark to start with or you will not be able to make minor changes and stay competitive. Setting up a race car is one of those deals where "The more you know, the more you know you don't know." Even the most veteran crew chief learns something new each week. Meticulous record keeping is an absolute must for the modern crew chief. There is no way he could operate without good test, practice and race notes.

You can drive yourself nuts chasing all of the variables in an effort to get your driver comfortable in the car only to have something that was out of your control happen and ruin your day. Maybe a shock starts to fail or a steering rod gets bent and the whole equation changes in an instant. Even a moderate change in horsepower can throw the setup off because everything -- engine, transmission and rear end gearing, front end geometry and suspension -- is tuned to work in concert to optimize performance.

Plus what you can do to a car during the setup phase is limited by NASCAR's well-defined rule book. You have to maintain minimum ride heights and weight percentages, etc. And, NASCAR dictates detailed specifications for individual pieces and parts so you have a limited playground in which to operate. NASCAR will often dictate what rear gears and/or shocks that a team must run at a specific track. That would require that the crew chief work backwards to match the rest of the car to the mandated parts.

That is why you are hearing so much grumbling about the COT at this point in its development. Too many unknowns are driving the crews and drivers nuts while they are trying to figure them out. Not to mention Goodyear and some of the suppliers who have gotten caught behind the curve a couple of times this year. The stakes are high so the more uncertainty the teams feel about their race cars the more anxiety they will feel as well.

From what I've seen to date, the guys who prefer driving a loose race car versus a tight race car have the advantage at this point of the COT's development. A loose race car is a fast race car if you can hang on to it and keep it off the wall. Kyle Busch seems to be the best at that right now. In fact, I'm betting that Kyle is really enjoying seeing those Hendrick cars in his rear view mirror right now.

Bill Borden is a former championship winning crew chief who operated David Pearson's Racing School for many years.