Advanced Driving Guide

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This section gathers as much info as we can find on advanced driving. You'll notice very few articles are by me, I'm not an expert but we do know some :) This guide will attempt to break out the key principles you will want to work on to make yourself faster each and every track day.

Contents

Smoothness vs. Decisiveness

Performance driving is about being two things, which are opposite -- smooth and decisive. The smoother you go -- the faster you go. And yet, many advanced driving instructors lecture too much about smoothness, forgetting that the driver also has to be decisive and quick, if he wants the car's reaction to be the same.

The car has limited and generally small amount of traction to work with. This traction is divided between front and rear (longitudal) and side to-side (lateral), according to applications it receives: steering (lateral), braking and accelerating (longitudal). Being smooth, without jerking the car, will enable to make the most out of the existing amount of traction. In motoring, you will find yourself at 90% of your traction. Meaning that, should something (and even a very little thing) happen, the chances of recovery will be close to zero, no matter how much experience you have. That's because, regardless of whatever techniques you are using (even with great skill), you just don't have any more traction left to work with. That's why you should be smooth, and keep the car under control, not skidding all over.

However, as you progress, you don't want to sacrifice speed for smoothness. With experience and skill, you need to find a balance between being smooth, but still being quick, and in times, almost aggressive.


Driver Preparation

Mental Imagery

Spend some time the days before heading to the track (especially if it is a new one to you) visualizing the track layout and how you would drive it in your head. If there are videos of the track or guides browse them over and while everything might not apply directly to your driving style or vehicle visualize what you would be doing on the track at those spots.

Many professional drivers place stop watches in their hands sitting in a chair and visualize a complete lap around a course they are familiar with. They work on hitting the correct braking zones, turn in points, track outs, and shift points. Do this for 20-30 minutes each day leading up to the event and you should start to see your lap times on the stop watch very closely mirror your best real life lap times. This is a great way to re-familiarize yourself with a circuit and work on getting the right line correct in your head.

Foot Work

Good foot work is a staple of being able to be quick behind the wheel. These techniques have been proven to improve lap times.

Left-foot braking

This is a technique where the left foot is used not only to manage the clutch, but also to use the brakes. This enables the driver to move from acceleration to braking without any coasting, enabling a much more accurate weight shift when approaching or turning into corners. It might take a bit of adjustment to get used to, since the left foot, having to engage the clutch, will not have the sensitivity of operating the brakes.

Heel and Toe

Left foot braking is reconmended, but Heel & Toe is a technique crucial to master. It involves simultanously braking (before a corner), and revving up the engine. To do this, the driver must use his right foot to operate both throttle and brakes, by placing the foot vertically, using the ball (on the brakes) and the heel (on the accelerator). The car is than put under braking, slowing it down before entering a corner. The left foot than de-clutches, as the most appropriate gear is selected and the heel is used to rev the engine with the clutch engaged. Than, release the clutch and turn into the corner.

Hand work

Steering techniques vary and have multiple approaches to them. However, some techniques are better than others and will improve lap times and reduce fatigue. Steering in racing must be smooth and progressive, in order to avoid needlessly shaking the car. However, it is a common mistake, to steer "too smoothly" across the tighter or more slippery corners. In sharp corners, the steering input must be made quite quickly, almost sharply, but without turning the wheel excessively and without jerking the car. Such an input will generate a response from the entire suspension and chassis, leaning the car into the corner, to allow it to be taken more easily. Additionally, friction created between the front tires as they rapidly change direction, will slow them down, thus shifting weight over them to increase the available grip. In wet or sllipery conditions, the car might respond to such an input with a slight "delay", but if you do not turn the wheel even more to "force" it into the corner, it will turn-in in an ideal manner.

Steer through the flat curves and bends with the hands located at 9:15. Steer around the sharper corners by relocating the hand and the direction of the corner and pulling the wheel from under the opposite hand, which stays stationary. To bring it back straight, relocate the opposite hand and pull back.

On Track Work Items

Anyway, I'd like to share two concepts that he shared with us:

Cornering

In track racing, and in any sort of motorsport, cornering is 90% of the race. The car is riding on four tires, each of these tires gripping the ground with a contact patch no bigger than a shoe. This traction is limited, and is divided between the different applications: steering (lateral forces), braking and accelerating (longitudal forces). It is no problem, therefore, to utilize all of the traction to a single application when you are traveling straight on. When you turn, you need to balance out the different factors involved, or you will be wiped out or -- alternatively -- simply be slow.

Brake ENDING point.

On the track, we all understand the 'Brake starting point.' Often in the pits, and here on the Rennlist, we discuss where we brake, IE: the STARTING point of when me have our foot on that middle pedal. We equate our braking zone to the point at which our foot first hits the brakes. "I brake at marker 200" or "I start braking at the crack in the asphalt just before the notch on the wall"...etc. Unfortunately, many people tend to have a starting point too early, and some have their points too late. Some over-brake, others underbrake and hang on for dear life whilst whipping around the corner - entrying the corner too fast, only to compromise their exit speed. All in all, it seems that we are not too consistent in the braking zone. (At least that's my case in many corners)

However, Ross contends that there may be a way of becoming more consistent in the brake zone - instead of focusing on the starting point of the brake zone, Ross Bentley suggests that the driver look further down track and focus on the brake ending zone - or somewhere around the turn in point of the corner. By focusing on this, and programming your driving on the track to adjust your braking based on this reference point, Ross argues that the braking will become more consistent.

By the way - we do this all the time on the street - at every stoplight, every stopsign, everytime we need to stop we aren't using a 'brake starting point' reference, but we're using the 'brake ending point' to judge when we start to decelerate and apply the clampers. So we already know this technique! On the track, it's just a little different - we don't stop completely (though it may feel that some do!) and we don't wait for the light to turn green before turning the wheel.

A common mistake is to be "too smooth" with the initial braking application. A "Regressive" approach to threshold braking is better than a "Progressive" approach. I.E. It is better to start off relatively hard and release as nessecary, than to start off too weak and increase progressively. Applying the footbrake should not be by "stomping" on it at once, but you should not "squizze" it down either. You should quickly but smoothly press it. At normal racing speeds, the initial pressure should be very strong, because the car is going fast, and much affort has to be put in in order to slow it down. As the speed decreases, less effort is needed. The driver should quickly apply hard braking, and progressively release pressure throughout the whole braking zone before the corner ideally maintaining a perfect threshold braking through out the entire procedure. In reality, a beginner that follows this technique might find out that he has momentarily locked-up his front tires or activated the ABS at the begining of the application. Note that a car on locked wheel is still slowing down very quickly, so the "regressive" approach is still preferable.

Trail Braking

Yes, Ross brought this subject up in the Advanced Driver's Seminar. Too bad ColorChange isn't here on Rennlist anymore. Ross suggested that trail braking is a helpful technique that can be used to overlap the braking zone and the turning of the car. He also suggested that it is helpful to rotate the car.

HOWEVER: he did mention that trail braking isn't the best technique in all cases. In fast turns with a great radius, trail braking should not be used - it would slow the car down too much. In tighter, slower, hair-pin like turns, trailbraking can be an effective technique to get the car rotated through the turn, and to overlap the braking zone with the turning zone.

In terms of newbies learning to drive on the track - he felt that the 'braking in a straight line' technique that many instructors teach may not be the best - after all, you are essentially teaching a student how to do something incorrectly. However, he also warned that instructors shouldn't advocate trailbraking for a new student either - newbies have plenty of other things to worry about. That said, Ross stated that many drivers develop trail braking naturally - and that if that is the case with a student, an instructor shouldn't discourage the trail braking student, provided he's doing the technique properly and for the right corners.

With trail braking, the brake input can be put in later when approaching the corner, allowing to carry up speed to a greater distance. Additionaly, feathering the brakes into the corner will improve traction to the front tires, which are the ones guiding the car through the corner. Initally, start by braking as you approach the corner, easing off as you reach the corner (regressive braking). Than, as you are about to turn-in, release more pressure, to allow the shocks and springs to be free to stick the tires to the ground. However, as you turn into the corner, stay as lightly as possible on the brakes. Once the car has turned into the corner, you can release the footbrake and apply neutral throttle (Left foot braking will be helpfull here).

Contributors

John Hajny

Central NY Region PCA Chief Instructor - PCA National Instructor/Mentor

Excellent set of articles on driving

Ross Bentley

The is the author of the Speed Secrets series, has been racing for the past 29 years, and has been coaching on all levels for 22 years. The man knows a bit or two about performance driving.