Managing Vehicle Balance

By David Rossiter

Active management of your car’s balance is an essential element in high performance driving. Unfortunately, it is frequently overlooked, especially by intermediate-level drivers, whose attention is often focused on more immediate challenges, such as learning the best line through a turn, shifting gears at the right places, and trying to handle that extra bit of speed.

Here’s a common scenario in PCA Driver Education events: You’re trying to increase your speed through a right-hand turn at the end of a fast straightaway. You know where you want to apply the brakes, where you want to steer into the turn, where you want to clip the inside apex, and where you want to exit the turn. Everything goes as planned, except for one thing: Through the middle of the turn the car leans strongly to the outside of the turn and puts you hard against the driver’s door. Instead of pushing you back into your seat, your car acts like it wants to throw you out the window. You make it through the turn, but instead of feeling good, it feels uncomfortable and insecure.

That’s being out of balance.

We didn’t need to think about balance when we first learned to drive because at normal street speeds balance is not important. After all, a car has four wheels, so it’s not about to fall over. However, balance is critical for a riding a bicycle, so as little kids we had to learn to control bicycle balance. We learned this skill so well that – even without practice – most of us can have no trouble controlling the balance of a bicycle with little conscious thought.

If you want to improve your high performance driving skills, you need to be able to control your car’s balance just as skillfully and automatically as on a bike. The off-season is a good time to build this skill.

What’s needed here?

When we first learned to drive, most of us learned a simple, standard formula for executing a turn in a car: (1) apply the brakes to slow the car; (2) steer the car through the turn, and (3) apply power once the car is pointed the correct direction. This formula is perfectly adequate for a slowly moving car that generates little momentum, but it has no way to manage the centrifugal forces that are generated in high speed driving situations such as the example described above.

What’s lacking in the 1-2-3 formula is the use of power to stabilize the car through the turn. Forward acceleration, added early in the turn and gradually increased throughout the turn, serves to balance the centrifugal force that pushes the car to the outside of the turn. A physicist would describe this as a forward vector modifying an outward vector, resulting in a vector that propels the car through the turn. The driver feels this as being pushed back into the seat, rather than against the door or out the window.

The hardest part of this for beginning and intermediate students is bringing themselves to add power early enough in the turn. We have years of practice that reinforces the simple 1-2-3 turn formula, so it can feel strange and uncomfortable to put your foot on the gas when you have just begun to turn the car. Moreover, it can be hard to make yourself add power early in the turn if you’re already going slightly faster than feels comfortable – which is likely if you’re trying to improve your performance. But you gotta do it!

Adding power early in the turn does not mean abruptly mashing the gas pedal. Power must be applied gradually and smoothly so as not to upset the car. In the middle of a fast turn, we need all the stability we can get!

What can you learn in the off-season?

The off-season is a good time to build your sensitivity to vehicle balance. If you pay attention, you can sense your car’s balance as you drive on the street, just as you can on the track. You can feel forward acceleration when you press on the gas pedal, lateral acceleration when you turn the steering wheel, and rearward acceleration when you apply the brakes. You can feel a sequence of rearward, lateral and forward acceleration as you turn a corner and you can feel how a tiny bit of acceleration (it doesn’t take much at street speeds) in the middle of a corner alters the centrifugal force that you feel. You can also feel the difference between an abrupt transition and a smooth one.

Of course these forces are not nearly as strong as they are on the racetrack, but they are easy to sense if you simply pay attention to them. And you’ll discover that when you increase your awareness of your car’s balance, you find yourself automatically making fine steering and throttle adjustments to manage that balance. Soon you’ll notice that you are using the steering wheel and gas pedal together to regulate your car’s balance at the same time that you are observing the traffic, listening to the radio, or carrying on a conversation.

You can do this in any car or truck. Of course, your big, high Suburban responds much more slowly than your tight little Porsche, but the forces are precisely the same.

At first it may take some conscious effort to focus your attention on your car’s balance. However, the more you practice, the more it will become something you do without thinking about it – just like when you ride your bicycle. Then, the next time you take that right-hand turn at the end of the fast straightaway, you’ll find yourself using steering and throttle together to control your car’s balance through the turn.