by Ross Bentley
CORNER-ENTRY OVERSTEER
Oversteer is often a result of too much weight on the front tires and not enough on the rears. If that is the case during the entry phase of a corner, that probably means you are braking too hard into the corner; you are trail braking too much.
The cure then is pretty simple. Just begin braking slightly earlier, and trail off the brakes a little sooner as you enter the corner. Perhaps, especially if it is a corner that requires little to no braking, it is a matter of beginning to accelerate sooner (but very gently), transferring more weight onto the rear tires.
ILLUSTRATION 34-3 Corner-entry oversteer.
Again, when you are chasing another competitor, it is easy to fall prey to the “brake late and I catch him” impression. Always keep in mind that you will gain more, both on your competitors and in reducing your lap times, by early acceleration than you will by late braking.
One other thing that may help reduce corner-entry oversteer is to turn the steering wheel less abruptly. Ask the car to change directions, from straight forward to a curved path, a little more progressively.
MIDCORNER UNDERSTEER
Usually the best way to handle midcorner understeer is simply by smoothly modulating the throttle to change the weight balance of the car. In other words, just breathe. Gently lift off the throttle to cause some forward weight transfer, giving the front tires more grip.
Often the understeer is not related to the car’s setup, but you have gotten back on the throttle to begin accelerating just a little too abruptly or early. Again, just breathe the throttle to transfer some weight forward.
ILLUSTRATION 34-4 Midcorner understeer.
Also, just like with the entry understeer, be aware of the amount of steering input you have dialed in. Perhaps the cure to your car’s midcorner understeer problem is just unwinding the steering a little bit to allow the front tires to get some grip.
MIDCORNER OVERSTEER
Dealing with a midcorner oversteer is almost always done by changing the car’s weight balance. In this case, that means squeezing more throttle on. However, one of the reasons the car has begun to oversteer is that the speed you are carrying is slightly more than the rear tires can handle. So the last thing in the world you need right then is a bunch more speed. That is why it is critical to squeeze on just a little more throttle.
The midcorner oversteer could also be caused by wheelspin (in a rear-wheel-drive car, of course), which should be dealt with by being a little easier on the throttle.
ILLUSTRATION 34-5 Midcorner oversteer.
If your car’s setup is the cause of the wheelspin, about all you can do is be as gentle as possible with the acceleration and possibly alter your line slightly. If possible, try driving the car a little deeper into the corner before turning in, make the initial turn radius a bit sharper, aim for a later apex, and then let the steering unwind as early as possible. This makes for a straighter acceleration line, meaning that there will be less cornering force to combine with the acceleration force that you are asking from the rear tires.
EXIT UNDERSTEER
If your car has an exit understeer problem, the best thing you can do without reducing your acceleration is to alter your line. Your prime objective is to lessen the amount of time you are turning the car while accelerating. So if you turn in a little later and sharper (even if this means slowing the car down a little), and aim for a later apex, it will allow you to unwind the steering a bit earlier. That means you will be accelerating in a straighter line, reducing the harmful effects of the understeer.
And one more thing: The more gentle you are with the acceleration, the less understeer you will have. If you jump on the throttle, the understeer is going to be exaggerated. So squeeze the throttle.
ILLUSTRATION 34-6 Exit understeer.
EXIT OVERSTEER
Exit oversteer can be related to one of two things: Either it is power-oversteer, caused more by the car’s inability to put its acceleration traction to the ground; or it is due to the weight balance.
Usually, the way to deal with either type of exit oversteer is much the same as with exit understeer. The goal is to open up the exit of the corner, increasing the radius of the corner as soon as possible, by using a later turn-in and exit.
ILLUSTRATION 34-7 Exit oversteer.
One of the other things you have to keep in mind with exit oversteer is to be gentle with the throttle under acceleration. If you stand on the throttle, even if you have altered your line, you are going put a big load on the rear tires. In time, this will overheat them, making the oversteer problem worse, even causing it to oversteer in other parts of the corner.
There is one other approach to dealing with a car that oversteers at the exit of a corner, especially one that has an extreme oversteer problem, and that is to almost give up, or sacrifice that part of the corner. Instead of slowing the car down and using a later turn-in and apex, you pretty much do the opposite. As you approach the corner, you brake later and carry much more speed into the corner, taking an earlier apex, and then get the car straightened out and pointed down the straight well after the apex. The idea here is that since the car will not accelerate out of the corner very well, you might as well try to take advantage of where the car is working—the corner entry.
Before using this technique, I would make sure that every other technique didn’t work, as you will not be setting any track records using this approach. It is a bit extreme! Once in a race, however, it may help you hold off a competitor behind you, at least for a few laps. Perhaps the biggest challenge in using this technique is that it is unlikely you have a mental program for it. Therefore, you may just want to try it on a test day or during a practice session sometime so that you are prepared for it.
BRAKE FADE
Brake fade is one of the scariest things a race driver ever experiences, but unless you want to just give up and pull into the pits every time it happens, you are going to have to live with it at some point in your career.
Typically, there are two reasons for the brakes to fade, both having to do with overheating. The first and most common is when the brakes get so hot from the repeated use that the brake fluid in the system begins to boil. As it boils, air bubbles are created. Unfortunately, air is much easier to compress than brake fluid, so that your brake pedal becomes soft and spongy, sometimes to the point that the pedal travels all the way to the floor without applying much pressure to the brake pads.
The second reason for brake fade has to do with the overheating of the pads themselves. In this case, the temperature of the pads has risen to a point beyond their designed operating range. When that happens, a gas is actually boiled out of the pad material, but it doesn’t just float away. It forms a layer between the pad and the brake rotor surface, acting almost like a lubricant. With this situation, the brake pedal stays nice and firm no matter how hard you push on it, but the car just doesn’t slow down very well.
In either case, the problem you have to deal with is the overheating of the brake system. The only thing you can do is allow the brakes to cool down, which is not an easy thing to do when trying to drive at the limit. In reality, there is no way you can drive at the limit, at maximum speed, while cooling the brake system. There are, however, some ways that you can allow the brakes to cool somewhat without it affecting your speed too much.
As I’ve talked about previously, braking later for corners does not gain you much. There is more to be gained when accelerating than there is when braking. Therefore, braking a little bit earlier will not hurt your lap times that much, as long as you brake lightly so that your corner-entry speed is just as high as it was before. Braking lightly means less heat going into the brake system.
The overall goal, actually, is to put as little heat into the system, while letting it cool as much as possible by allowing air to flow through them.
If there are any places on the racetrack where you now come off the throttle and brake for a short period of time, this is an opportunity
to help the brakes cool. Instead of touching the brakes, just come off the throttle a little more, or longer. Even if you had been using the brakes for a fraction of a second, by not using them here you are allowing the air to cool them without adding any more heat to them.
AILING GEARBOX
The first thing to consider is why the gearbox is beginning to fail. Is it because you are not blipping the throttle enough on your downshifts (probably beating up on the dog rings)? Are you lifting on your upshifts? Have you missed one shift, damaging the dog ring, and now it pops out of that gear?
If you are driving a car with a sequential shift, there is not much you can do about how you place the gearbox in gear. It is just a matter of pulling backward or pushing forward all the way, being firm and positive with it. But you can control the use of the throttle. On upshifts, make sure that you exaggerate the throttle lift, which takes the load off the dog rings prior to moving to the next gear. And on downshifts, make sure you are blipping the throttle enough.
If you do not have a sequential shift gearbox, there are a couple of other things you can do besides what I just mentioned about the use of the throttle (which apply here as well). The first, and most obvious, is to make sure you do not miss any gear changes, even if that means shifting slower and more deliberately. But just as I said with a sequential shifter, be firm and positive with your shifts. Just as many gearbox failures have occurred by “babying it” too much, as from being too rough.
With a troublesome nonsequential gearbox, you can work at “placing” it in gear a little more. Be precise, but firm and positive. If it begins to pop out of gear, that means the gearbox dog rings have worn. About all you can do is make sure you do not miss any more shifts and try holding it in the gear that is having the problem.
Whether you use the clutch or not to shift is an important factor. If you do not use the clutch, and the gearbox begins to get difficult to shift, won’t go into a gear, or pops out of gear, you may want to try using it. If you have been left-foot braking and now need to change to right-foot braking to allow your left foot to work the clutch, that will be quite the change. If you do not have the mental program to drive that way, it may be a bit too much of a change to make in the middle of a race. It may be something you want to try in a practice or test session someday.
If you are driving a car with a synchromesh transmission, like a production-based car, you may want to try double-clutching if it begins to get difficult to get it into gear.
DIFFERENT CARS
Some would say that driving a production-based car, such as a front-wheel-drive sedan, is all about adapting, and that “real race cars”—purpose-built open-wheel cars—don’t require adapting. Their point is that the purpose-built race car should do what you want it to do, at least if you’ve done your job of setting it up correctly. While I would agree that production-based cars often require a little more adaptation, I disagree that a purpose-built car does not require you to adapt your style.
I can tell you from personal experience that production-based race cars can be some of the best all-round balanced and setup cars in the world, while some purpose-built formula cars are far from it. And yes, setting up the car perfectly is ultimately your responsibility. However, it’s rare that you will drive a car that is perfect. In fact, by definition you cannot have a perfect car in every corner. If you get a car, purpose-built or production-based, to work perfectly in one corner, it’s next to impossible to be perfect in every other corner. The laws of physics will back this up.
So how do you adapt your driving to suit the car and track? Here’s a list of just some of the things you can do:
• Alter the timing of when you turn into a corner.
• Alter how quickly you turn the steering wheel into a corner.
• Alter how long you keep maximum steering input in the car through the midsection of the corner.
• Alter the timing and how quickly you unwind the steering out of a corner.
• Alter the timing of when you release the brakes when entering a corner.
• Alter the rate at which you release the brakes when entering a corner.
• Alter the time you spend between fully releasing the brakes and the initial application of the throttle.
• Alter the rate at which you apply the throttle exiting a corner.
• Alter how much and how abruptly you modulate the throttle.
Each one of these approaches can be altered in isolation, as well as in combination with any other(s). So, how well can you adapt and alter each one of these techniques? If there is even one of these that you are not adept at adapting to, you are not as complete a driver as you could be. Learn to alter each one and to combine them in the perfect way to make the best of every corner. Some drivers are great in certain types of corners and not in others. The reason is that they can adapt in some ways, but not in others. They are not adaptable drivers.
As a strategy, take parts of your test sessions and just practice these different approaches. Try turning in a little earlier and slower or later and crisper. Try gradually feeding in steering all the way to the apex and then unwinding it, as well as feeding in all the steering early in the corner, holding it there for most of the turn, and then unwinding it at the end of the corner. Try trailing off the brakes more slowly and then coming off them relatively abruptly. Try being patient from the time you come off the brakes and before you begin applying the throttle, and then making those two almost overlap. Try playing with the rate at which you feed in the throttle and modulate it. Make note of what all of these approaches do. If you know what one of these do, when you need the car to do something, you will automatically and naturally give the car what it needs.
SPEED SECRET
Give the car what it needs so it will give you what you need.
UNDERSTEER-OVERSTEER PROBLEM
How many times have you complained about the car understeering early in a corner and oversteering toward the exit? I don’t know of a driver who has not driven a race car at some point in his or her career who does not do this. If drivers haven’t yet, it is only a matter of time before they do.
Engineers hate this problem. After all, the cure for half of the problem often exaggerates the other half. The biggest problem, the real problem, is that the problem is not always the fault of the car. The problem often lies with the driver.
The solution? Ask yourself (or have someone else ask) some awareness-building questions. A common cause of this handling problem is that as you experience understeer early in the corner; you turn the steering wheel even more. Think about it. You’re entering a corner at 100 miles per hour, you turn the steering wheel, and the car pushes toward the outside edge of the track. What would you do? Probably the same as many drivers do: crank in more steering angle, trying to get it to turn. It is human instinct. It is survival instinct.
If you ask yourself exactly what you’re doing when the understeer occurs, you begin the awareness-building process. Ask, “What position do I have the steering wheel in when the understeer occurs?” Give yourself time to think about it. Close your eyes and visualize what was happening.
At first you may answer no. You know that is the “right” answer. But keeping thinking about it and ask yourself questions. Don’t be in a hurry for the answer. Think it through, preferably visualizing what you had been doing.
Often, you will become aware of the fact that you actually turn the steering wheel more when faced with the early-in-the-turn understeer. You will then realize that when you do that, it causes the oversteer later in the turn. What is happening, of course, is that as you turn the steering wheel more and more, the front tires begin to scrub off some speed, then suddenly regain traction, causing the car to snap to oversteer.
By simply becoming aware of what you’re doing, as a result of your questions, you have discovered the solution to the problem, not cranking in more steering input. Your next step is to develop your MI. You could ask yourself what you should do and how t
hat would look, sound, and feel. Describe in as much detail as possible. Close your eyes and imagine it in as much detail as possible, and do that over and over, daily, weekly, and monthly.
The key is defining the real cause of a problem. There are many times when the car is not the problem; it is you that is causing the problem. Far too many teams have been led down the wrong path by not digging to the core of the problem. They chase the effects of the problem. Before you tweak away on the car’s setup, raise your awareness to determine the real cause of a handling problem.
It used to be that a book like this only talked about driving road courses. But more and more forms of racing in North America are including oval track races. I’m not going to go into great detail about strategies and so on, but let’s take a look at some basic techniques and tips specific to driving on an oval.
SETUP
First, car setup. Generally, the car should be set up to understeer slightly, not oversteer. It’s next to impossible to control an oversteering (loose) car on an oval, due to the consistently high speeds. You may be able to control it for a couple of laps, but eventually it will catch up with you, sending you spinning into the wall. On an oval, you want to base your car’s setup around what the front end is doing, not the rear, as you would on a road course.