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Astraist
Master Driver



Joined: Mar 27, 2010
Posts: 209

PostPosted: Thu May 12, 2011 4:22 pm Reply with quote Back to top

I bring this thread in response to the very nice technical discussion I had with our (new?) friend GerardWon. Other readers, if they do track driving (and I highly recommend it) are for sure welcome to be interested. This track driving guide is for you (even though I'm sure Gerard can benefit from reading it, too).

Moreover, most of the discussion will be relevant in some way or another to normal road driving. If you didn't drive a racetrack before, I suggest doing it soon. It can sharpen important driving skills, especially with a good instructor!

About Motorsport, track driving and road driving
Motorsport describes all disciplines of competitive driving in cars, bikes, boats and planes. It is also a physical sport due to the great loads working on the bodies of most race drivers, but it's mainly a competitive sport. Like most sports, olympic swimming being perhaps the most staggering example, racing is technique-dependent. Simply trying to go fast won't do it. You need a good trainer and you need to work on doing things in the proper technique. Only than can speed emerge, as a by-product of proper driving.

The basics of proper racing technique are shared to ALL fields of motorsport and even for road driving. Good race drivers are usually good road drivers, and countries with a flourishing motorsport usually have a good driving culture and less collisions. Everything I've talked about earlier in this board has it's origins in racing.

This is the time to discuss the differences between two "disciplines" in driving race cars: Rallying and Track driving. Rallying is performed on closed public roads, either gravel roads or tarmac roads. I'm secluding rally-raid leagues, that focus on driving through challenging terrain while navigating towards a remote destination (Like rally Paris-Dakar). Track driving is performed on a closed track.

The difference is that the track offers a more "sterile" and anticipated environment. The driver goes around the track dozens of times and professional racers go hundreds of times (in one day!). The result is that they know, within a range of one-two meters, where they brake, where they steer and where they accelerate. The focus is on taking the known and predetermined technique and tactic into perfection.

Rally driving offers a greater potential for surprises, problems and a lesser margin of error. This allows for less accurate a driving style, and for a lesser ability to drive the car to it's fully performance envelope. The driving style is often a bit more "sharp" and the car is sliding a tad more than a race car. In gravel rallying, the drivers often have no choice but to slide the car altogether into a corner, even though the highest speed is always received when the car is not sliding. Rally cars are driven more with the feet and the pedals, than with the steering (70-40 precent)

The Cars
I begin with analyzing the basics of the cars' calibrations. Race cars are quite different from road cars. The open road, unlike the track, offers less consistent grip levels, and a greater chance of cracks, bumps, slopes and what not. As a result, the cars are equipped with treaded tires and with soft suspensions.

Race cars can be first distinguished by their use of fat, low-cut tires that, in professional track cars, are perfectly slick (no tread) for more rubber to-road contact. With the track surface being so smooth and the tires being so grippy, the suspension can be greatly stiffened through use of shorter and stiffer springs, dampers, anti-roll bars and chassis. A stiffer car reacts more sharply and, given the conditions I stated above (smooth surface and grippy tires) will have more grip.

The downside is that such cars have to be driven with accuracy and smoothness. Being sharp, aggressive and insensitive to the car's limits, will make the car break away more sharply than any road car ever will. In fact, in full racing pace, occasional slides are virtually irrecoverable. The stiffness, light weight and low center of gravity are devised to create a car that doesn't like weight transfers. It's driving is about 55% with the feet (gas/brakes) and 45% hands (steering).

Rally cars, however they are also light, powerful and stiff, have a calibration that is more close to that of a road car. They react quickly to weight transfers and pedal inputs, and they can be driven with sharper inputs (but nevertheless smooth!) and with greater weight transfers and an overall larger "slip angle". All cars, on all surfaces, will be slower sliding sideways than they will be in "clean" driving. However, when you drive a car and exploit every bit of grip, you find that the car is in fact sliding very slightly. Rally cars simply reach their limit at a greater slip angle.

The driver
Race drivers need to be very fit for Stamina and Aerobic stress on the shoulders, forearms, crura and neck. They usually drive cars with special racing seats, for better body support and safety in high G-force crashes (when applied with a roll-cage). They also use racing harness with five to seven points (unlike your average three-point belt). They also use helmets and neck protection fireproof clothing and special, thin-soled racing boots.

The driving position is crucial for the racing driver. He/she usually spend full sessions on adjusting the driving position just about right. A renowned local trainer where I live, one Re'm Samuel, would spend half a day's worth of practice sessions on getting the driving position right. It begins with measuring the driver's height and the length of his arms, legs and neck. This is especially crucial if you can have someone build a custom-made racing seat for you.

The next stage is the adjustments. They are made separately for the seat's placement, the steering placement, and the pedal placement. You first make a basic adjustment of all of these, go out for a ride, check how it feels, and than make little pedantic corrections with the seat. You than go again and make little tweaks to the steering, and than for the pedals. Here are a few guidelines:

1. "Don't sit on the seat, sit IN it." You need to push your buttocks into the seat's base and reach full contact with your back. If you go for a custom racing seat, or if your own seat has the adjustments allowing this, you should make sure the back, shoulders and thighs are fully supported by the seat when you press the pedals or turn the wheel.

2. Make quick adjustments of height, distance and angle of the base of the seat for comfort.

3. Now, adjust the seat forward so you can press all pedals fully, especially the clutch, dead pedal or the brakes, while still maintaining a decent bend in your knees. For racing purpose, the knees should be bent at about 120 degrees. Any less makes you lose the leverage on the pedals because your thighs cannot generate torque around the knee joint. Likewise, a bolt-straight knee will result in severe orthopedic injuries in a collision (the force be absorbed in and projected through the bones, not the muscles). The check should be done after starting the engine and pressing the brakes a few times. Open-wheel cars should allow for a more shallow angle at the knee (about 140 degrees).

4. Adjust the backrest to as parallel to the steering as possible. Simply erect it to a relatively upright position (About 100 degrees) without having it standing fully erected in 90 degrees.

5. Now, adjust the steering so that it is close to you, and as parallel to the angle of the back-rake as possible. Of course the steering needs to be high enough so that you can see the instrument cluster and hold/operate it easily. You should be able to stretch your arm forward so the wrist can rest flat over the wheel without fully outstretching the hand forward and without leaning the back forward. Note, the wrist should be able to rest flat over the top of the wheel. If you can only touch the face of the wheel with your wrist you are too far from the wheel/in an angle relative to it. Your arms, gripping the wheel, should be bent at about 90-100 degrees. In open-wheel cars, you should be further to the back, but you should be able to grip the wheel at the top with the elbow bent and the back in the backrest.

6. Use the seat height for clear sight of the road and instrument cluster. You should have a clearance of a hand-width (five fingers) between your head/helmet and the ceiling. Your palms gripping the wheel should be just lower than the shoulders.

7. Adjust the angle of the base of the seat so that it supports your thigh fully when you press hard on the pedals, but so that it does not interfere with pressing any of the pedals. The seat's cushion should be in contact down to your knees, but without applying pressure behind the knee. Make sure that under strong braking or when pressing the clutch, you can squeeze your fingers below the thigh, to ensure you press on the pedals, not the seat.

8. Place hands on the wheel at 9 and 3. The palms should cup the outside diameter of the wheel. The thumbs should be lightly hooked over the crossbrace of the wheel (on tarmac roads/tracks). Your right heel should be rested facing the brake pedal, with the ability to pivot right to press the gas. You should depress the pedals with the balls of the feet, and the throttle pedal should be operated from it's lower portion, for sensitivity. The left foot, whenever not clutching, should be placed on the left footrest. You can press against it to brace yourself in corners and while braking, so you don't have to hang over the wheel/pedals.

9. For other adjustments, talk to me. Wink

The basics of steering
On the track, most steering inputs are done with fixed grip. I.e. You just grip the wheel at 9 and 3, and use both hands symmetrically to turn the wheel as much as necessary. In open-wheel cars, the seating position and steering mechanisms are different, and we use fixed-input steering all of the times, including very sharp corners, where sometimes you can see drivers cross their forearms.

In tight corners of the track, or when driving on the road, or in a rally stage, you will need a more elaborate steering style and I suggest adopting the steering style I teach. I posted it in a very detailed manner in this thread.

The basics of Grip
In order to drive on the edge of the car's grip, you need to understand how it grips the road. You have four tires that give you four contact patches. Each of these contact patches gives you 100% of grip. You can use it for either braking, accelerating and/or cornering. If you use 50% for one input, you only have 50% left for other uses. If you use 100% for braking, you have zero left for steering.

However, when you brake, steer or accelerate, you move the car's center of gravity. When you brake, weight transfers forward to increase the grip of the front wheels (by pressing them harder against the road). Yes, some of the grip of those wheels is "used" for braking but, if you get it just right, you can increase the grip of the front wheels so they can help you turn into the corner faster. In the corner, after you turned in, you need to keep the car steady on "Balanced Throttle" -- just enough gas to keep the car at a constant speed, not slowing down or accelerating. Coming out of the corner, you accelerate.

Reading the road surface

* Dry tarmac/concrete -- 0.9-0.6; 2.2 on professional race-cars with heated tires, more on drag racing cars

* Wet tarmac -- 0.6-0.4; Depends on the pavement, the water depth, tire tread depth and presence of slippery agents on the pavement.

* Grass, earth, tight gravel -- 0.5

* Loose gravel, mould, rocks, clay, frost -- 0.4

* "First Rain" -- 0.3; Relevant to wet surfaces in significant presence of acrylics, oils and sand or dust. Can be found on the "racing line" when the track is wet, and near the edges of the track. On the road it's typical after a dry week, and especially around intersections and bus stops. Similar grip levels in hail.

* Mud, Slush, oil, Snow -- 0.2.

* Ice, deep water puddles, heavy-duty transmission oil, wet epoxy -- 0.1


The basics of handling
When a car exceeds it's limits of grip, it will slide. To put it more precisely, when the car's tires exceed their limits, they (i.e. the tires) would slide. This is why we have different slides (or different handling), it all depends on which wheels are sliding. If the front wheels are sliding, the car is said to understeer. If the rear is sliding, it is said to oversteer. If all four are sliding, it is said to behave neutrally.

The front wheels are the wheels that we turn when we use the steering wheel. Hence, if they slide, they will not manage to turn the car, and the vehicle would slide FORWARD and out of the corner. This is less dramatic and more easy to recover from than from when the back is sliding (fishtailing) and it is the nature of all cars, due to the laws of physics.

Understeer is not a result of the driver understeering, it is a slide of the front wheels. It's not that you didn't turn the wheel, it's that the front wheels are sliding. So turning the wheel tighter into the corner is not going to be a very effective solution (even though it might work). The solution is to use weight transfers or, to put it in other words, use your feet. You need to ease the gas pressure until the car grips again. It might be necessary to ease off of the gas completely, or even to brake with feel. It's important to be smooth and gentle. Too much braking can make the understeer worst (because you will use grip for braking instead of turning) or turn into oversteer.

The way to ensure a proper correction is to FEEL the slide. The understeer slide occurs at the wheels connected directly to the steering wheel through the steering linkage mechanism, so you can feel it as the steering becomes "numb." At that point, before the car actually breaks away, you need to apply the correction. This will allow you to correct the slide very early, so you don't need to turn the wheel more, and you can actually wind the steering a tiny bit back to straight.

By winding off a bit of steering, you allow the car to react to the correction more quickly and smoothly. Say the car has developed a slip angle of 10 degrees, between where you point the front wheels and where the car is sliding towards. If you reduce the steering input by one degree, you reduce the slip angle to 9 degrees. Now you only have to compensate for 9 degrees.

Oversteer is a different story. Most people think race-cars should oversteer everywhere for good turn-in, but they actually naturally understeer like all other cars, and they exhibit a greater understeer tendency than many sports cars. Oversteer cannot be so accurately predicted through steering feel, but it can only occur after you finished turning the wheel into the corner, which helps you anticipate when it might occur. Also, if you hold the car on balanced throttle like I said earlier, the car will not be able to exhibit oversteer, it will understeer.

Oversteer will be caused by:

(a) A forward weight transfer. We said that slowing down or braking make the car nosedive and weigh down more on it's front, giving it more grip. However, the same extra grip at the front end comes on the expense of the rear. On the limit, inside the corner (after you turned in), it might cause the back-end to virtually go airborne and swing aside.

(b) Excessive power. Accelerating moves the weight to the back and gives the back more grip, making it less likely to slide and making the front likely to understeer. However, very strong acceleration in a powerful rear-wheel drive car will make the car swing it's back, because all of the rear tires' grip is being used for acceleration and not for cornering. This kind of oversteer is impossible for front wheel drive cars.

The correction should be quick and depends vitally on the driving position. A good posture allows to receive the necessary feedback from the chassis and recover in time. The correction also depends on the drivetrain:

1. In a front wheel drive car, you need to accelerate forward. The acceleration will shift weight to the back of the car and get it to grip again. Simultaneously, you need to unwind to steering

2. In a rear/all-wheel drive car, you need to keep the car steady on balanced throttle and correct the slide by turning the wheel towards the direction in which you want the car to go. You will actually be turning the wheel into the direction in which the back is sliding, and than straighten it back when the car grips again.

Note: Many unskilled racers, and even some professional, competitive racers, go wrong here. They recover from oversteer simply by turning the wheel into the skid, without much care for what they do with the throttle. This is wrong! In a rear-wheel drive or all-wheel drive, it's crucial to keep the car steady on constant throttle.

In a front wheel drive car, you shouldn't even reach a situation where you need to turn the wheel into the slide. You need to apply the throttle early enough and strongly enough so that all you need is to straighten the wheel back to straight. In powerful cars, it's even possible to get the front wheels spinning so that they push the car back into line. If you must countersteer, you need to keep balanced throttle like in the other drivetrains. Another extremity is when driving on smooth ice or on an epoxy skidpad. These surfaces produce ridiculously low grip levels, so you just bang down on the clutch and correct the slide with the steering.

In some cars, the formation of the rear, semi-trailing arm suspension, creates a tendency of passive rear steering, which makes the outside rear wheel toe-out under load. The result is that, under hard cornering, the car will begin to develop understeer. Any attempt to push the car beyond this point would make the tail of the car "step out", which might feel like oversteer, but will "balance" itself out immediately unless you let go of the gas.

Neutral handling is created when you enter a corner at speed with the weight of the car on the front wheels (light braking). This is the proper way to enter a corner in a racing pace. The neutral handling will turn into oversteer if you don't get on the gas, and turn into slight understeer when you do.

The basics of braking
In order to ensure full grip and full speed in corners, you need to take the appropriate line through the corners. The line begins in the straight where, on the track, you would be on full throttle for speed. However, on all but the fast sweepers, you will need to brake before the corners. So, you need to brake as hard as possible. By braking hard you can brake more in a smaller space, so you can stay on full throttle up to the very last possible second. On fast corners, if you don't need to downshift, you can even learn to do this braking with the left foot, to shave off those precious tenths of a second when you move from pedal to pedal.

Remember the budget? Each wheel only gives 100% of grip. The brakes of a car are so strong that they can place such demands on the tires, that the tires be well beyond their ability to perform. By slamming the brakes all the way you are asking each of the four tires to do 400% of braking instead of the full 100% they are capable of. So, you need to brake with feel for the right point where the braking force is maximum. Below this point you are not braking to the full potential. Beyond it you are sliding and against not braking as effectively.

The problem here is not so much lack of smoothness but rather lack of decisiveness. You obviously reach the braking point at speed. This intimidates drivers as they now have to brake very hard and they brake all too lightly at first. Coming up to the corner they find themselves obligated to squeeze the pedal harder. This is a mistake.

In reality, the brakes have a harder time in stopping the car from a high speed, than they do from a slower speed. So, while braking from a higher speed might be frightening, it is in a higher speed that you need to brake harder and you will not get the wheels to slide. You need the strongest and quickest braking input when you begin to brake. Once you started to brake, the speed is clearly getting reduced, and the braking force increases. So, in order to keep the wheels just on the threshold of sliding, you need to constantly ease off of the pressure parallel to the reduction of speed, to keep the car just on that point.

By now you should match the gear (and apply the necessary rev-matching technique, to be referred to later) and this brings us to the point of turn-in, where you start turning the wheel into the corner. In this driving style, we trail brake, i.e. we carry this "threshold braking" into the corner. So we are braking on the edge of the tires' ability to slow down, using the full 100% of the tires' grip to slow down, and using just those 100%, nothing more or less. When we start turning into the corner, we find ourselves sharing the grip of the wheels for both braking and steering. So as we turn the wheel progressively into the corner, tightening up the angle, we should ease off of the brakes in the same pace. Once we finished turning the wheel into the corner, we should transition from brakes to throttle. This transition should be quick, but seamless.

This does not apply to emergency braking. In emergency braking you tread the pedal and let the ABS or locked wheels to do all of the work. If you don't have ABS, you better get a trainer to work on "Regressive braking" where you first slam on the brakes, and than you begin easing off of the pressure very gently until you find the threshold and keep it.

The basics of the driving lines
As we enter the corner, we need to turn the wheel smoothly from the turn-in point into the corner. The line we take should increase the radius of the turn by actually making the turn as long as possible, so we can carry as much speed into it as possible. This is achieved by turning from the outside, diving into the corner and clipping it's inside at the center, and than tracking out to the outside. For a left-hander, we would start at the right side of the road, turn towards the left side of the road just in the middle of the corner (the 45 degrees line) and than let the car run wide to the right as we get out of the corner.

This is the classic line. However, I have to introduce you to a few other lines: The early-apex, the classic apex, the late apex and the last apex. The early apex is the normal line that newbies take. They see the corner coming at them at speed, and they start turning the wheel into the corner early, along the straight. This allows to take a shallow and fast line into the corner, but than, just before the middle of the corner, they find that the nose of the car is still not pointed sharply enough, but rather towards the outside of the bend. This makes them slow down mid-turn and even into the straight afterwards. It might feel fast, but it's hopelessly slow.

The classic apex is just the line I described earlier. The apex is the point of tangent to the corner's peak, where we experience the most massive side force or tightest turning arch. However, it is the LATE apex which is usually the most desired line. It is the opposite of the early apex. Instead, you brake later and wait to turn in later. This makes you turn the car into the turn at a sharper change of direction, and clip the inside of the turn at a later apex, so the speed coming into the turn is REDUCED. However, as you reach that later apex, you find that you car is well aligned for the following straight, so you can begin accelerating out of the corner sooner and stronger.

This trade-off of prioritizing corner exit speed for corner entry speed is a very successful one, unless the car is much more grippy than it is powerful. The reason for this trade-off is simple: In the corner (and on the approach) you can only shave a few tenths of seconds because it is a more confined space. In the exit of the corner and the following straight, you can gain a few good seconds by being faster along the whole straight. The motto is "Slow-in, Fast-out."

This motto is intensified in what is called the "last apex." It is the apex even later to the classical late apex. It makes you take a very sharp and jerky line coming into the corner, but allows you to slingshot out of the corner at an almost straight line. This is a good line for rally drivers and for road driving, because it allows you to take a peek around the corner before you even turn in, but in racing it's only used in very slow hairpins (tight turns of 180 degrees) or in a pair of opposing turns: A left-hander closely followed by a right-hander.

Here is where a lot of people go wrong with this line: They are too gentle. For the sharp transient that the car must undergo to turn into the corner in this line, you need to turn the wheel quite quickly, even sharply. Racing is smooth by definition, so you shouldn't really "shake" the car, but you do need to turn it "decisively" into the corner, and than progressively wind it out of the corner. Some people are often too gentle on other corners as well.

Fast sweepers are very unique corners on the track. They allow the driver to take the classic apex line, allowing to carry as much speed as possible through the whole corner. These corners are usually taken with some throttle all along the way, and require slight and very smooth steering inputs through the corner. Once you turned the wheel, you need to control the car with the throttle -- a bit more throttle will mean more understeer and a wider line, less throttle will mean a tighter line with less understeer. But beware, if you let go of the gas in the middle of such a sweeper, you are very likely to make the car turn too tightly by making it oversteer. At these speeds, the ability to control oversteer is in times fictional. You need to avoid it, or recover as early as possible by picking up the throttle as early as possible.

With that being said, sometimes there is a slight problem where the car is not so obedient going into the sweeper. Either because of setup (mainly front-wheel driven cars) or the shape and slope of the sweeper, it might make the car generate too much understeer. This is yet another situation where the corner might require a "decisive" steering input that allows the car to rotate and "take a set" early.

Another point, which refers to all corners, is that you actually need to start turning before the turn-in point! You need to understand that it takes about 1/4 of a second for the tires to establish a slip angle and a cornering force (i.e. it takes 1/4 of a second for the car to react to your initial steering input), so we need to start steering a fraction of second before the actual turn-in point so that, at the turn-in point, we already have the wheel turned ever-so-slightly into the corner.

This is sometimes called "hinting" and it will give you the response you need from the car in just the proper timing. Note, however, that you don't need to intentionally "hint" the steering, you just need to start turning it a fraction of a second "too" early, with no change in the pace in which you turn the wheel. The whole turning procedure should be smooth and linear (and decisive when necessary).

The basics of Observation
The speed in which things occur on the track can be overwhelming, and make you miss key steps in the proper technique. In order to "earn" time, you need to be ahead of the car. The way to do this is to look further up into the track ahead. Instead of focusing on the ground in front of you, look up to the furthest possible distance, as far as the horizon where possible, and work on using your peripheral vision on getting you from here to there. Use your imagination to visualize the line you want the car to take up to that point.

Basically, we want to divide our driving between our foveal and peripheral vision. Our foveal vision, the sharp field of focus, can pick up details. Based on these details, it can process visual information into a "plan." So, we use our foveal vision to observe and plan our route as early as possible, which is why we strive to look as far ahead as possible. We use our peripheral vision to gauge the exact timing and quantity of our inputs: When to apply the brakes and how much, when to turn and how much, when to apply throttle and how much, etc...

This is particularly relevant to the corners of the track. In all but the very fast sweepers, we don't just keep our eyes up to the horizon like this, but we actually do something more sophisticated. Obviously we see the corner in advance along the straight. We take a peek into the corner and as far as possible through and beyond it. We use our imagination to sketch the line we want to take through the corner, and on this line we apply points for braking, turn-in, throttle, apex and exit. We should also have actual, physical and fixed reference points for at least the turn-in, apex and exit. The braking and throttle points are judged by feel and by our ability to visualize them in advance.

As we approach the corner, we want to be about one and a half steps in front of the car. So, as we reach the braking point we mentally visualized, we need to look at the (physical) turn-in point. We judge the exact moment to brake based our peripheral vision. As we get closer to the turn-in point, we shift our focus to the apex marker point (which should again, be a fixed, noticeable object along the track), and we judge the exact point of turn-in through our peripheral vision. As we get closer to the apex, we reach our speculated throttle point. Now is a good moment to shift the focus once again, so that we are focusing on the exit point, but driving through the apex with our peripheral vision. As we are about to reach the exit, we shift focus so we look down to straight in search for the next corner, while driving through the actual exit or track-out point based on our peripheral vision.

Here's a good example.

The basics of rev matching
In all situations other than taking a long downhill slope in a road car, we seek to brake the car with the brakes, not the engine, and the track is no exception. You already know that your wheels can only do so much braking before sliding, so you can assume that trying to slow down the car more by downshifting will not help or even make matters worst by making you slide. The solution is:

a) To downshift directly: Assume you begin braking when in fourth gear, after braking you reach a speed suitable for second gear. There's no need for third. Brake, and at the end of the braking declutch and put it into second gear.

b) Downshift smoothly: Operate both the clutch and shift knob with finesse. Put your palm over the knob rather than wrapping it around it like a fighter jet stick.

c) Use rev-matching: When you downshift, you need to apply some throttle to match the revs more accurately. The classic method is to declutch, put it in gear and than apply a bit of throttle as you ease off of the clutch. However, we we race, we do this whole process while braking, so we need our right foot to manage both the throttle and brake simultaneously.

The classic way of doing this is called "Heel And Toe" Because you press the brakes with the ball of the foot, while swinging the heel right to blip the throttle. However, different pedal sets require different manners of doing this. In cars with pedals at none-even heights, you need to swing the heel, but twist the foot around so that you actually press the gas with the side of the foot. In professional race cars either the rev matching be done by the automated tranny, or that you will have a pedal cluster that would allow to simply press both pedals simultaneously with both sides of the foot.

Some old race cars also needed to have this combined with double declutching, where you didn't blip the gas when the clutch was pressed, but rather declutched, shifted into neutral, let up the clutch as you matched the revs, and than declutched again while shifting into the lower gear.

The basics of sliding
In gravel rallying, the driver slides the car into the very slippery corners. They simply have to oversteer the car so that they know that the nose is pointed into the corner. Otherwise, it's too hard to avoid the understeer and still maintain a suitable cornering speed. They basically don't know what is going to happen inside the corner so they gain a bit of extra speed on entry, even though the "slow-in, fast-out" rule is more relevant than ever.

There is a set of provocative actions that the driver does to get the car to slide and do what he needs it to do: The first and most subtle manner of sliding is simply to brake into the corner (trial braking) and turn the wheel into the corner a bit sharply and pause. The car will oversteer into the corner, and you could pitch it outside by straightening the wheel and applying the throttle. If you slide the car as much so that you need to countersteer, you are losing speed.

The next technique is the "Appel Contre Appel", which amplifies the effect of the former technique by first turning the wheel out of the corner and than, just a fraction of a second after the first turning motion, you turn it back into the corner decisively. The effect is especially strong if you lift off of the gas just after the second turning motion, but in real competitive sport you do it all under braking. Again, if you have to turn the wheel against the corner, you made the car slide too much. This move shifts the car's center of gravity from the center to one side (generating understeer) and than from one side straight to the other side (generating oversteer).

The last technique is used only in extremely sharp corners, which simply cannot be negotiated in any other way. This is the handbrake. You brake, turn the wheel into the corner while keeping the button on the handbrake pressed (before actually pulling the handbrake itself). Just a fraction of a second after turning the wheel into the corner, you need to yank the handbrake to rotate the car into the corner. The handbrake should be yanked on the right moment and under braking.

Intentional sliding is also used in another motorsport - drifting. I will not delve into the details of this sport. It's too much and I'm not that good or knowledgeable at drifting as in racing or road driving. This sport is by definition applied only in powerful rear-wheel drive cars with a limit-slip differential. You start sliding the car, by use of any possible method: You can push the gas for a moment, you can sharply lift off of it, you can brake into the corner, you can kick the clutch when the throttle is on, you can suddenly shift into "too" low a gear, or bump the car over the kerbs of the track -- all in order to slide the car. The key is to have the tail of the car just drifting away from you, rather than getting a sudden sharp break-away which is too hard to catch and tenfold as hard to maintain.

Once sliding, you maintain the slide by applying massive amounts of throttle while steering sharply into the slide (opposite lock) to keep the car sliding sideways, as if it was sliding neutrally on all four wheels. Coming out of the drift, the steering and throttle inputs are reduced to a smooth recovery or, alternatively, to a pendulum where you aggressively swing the car and make it slide in the other way. This is very challenging to beginners because you have to apply the corrective steering input very early, especially in professional drifting cars.

The competitors in these events are rated by speed (30 points), line (30 points), angle (30 points) and general impact (10 points). In some stages of the competition they do tandem drifting and imitate one another as they drift in pairs of cars, and are rated for their ability to imitate one another. Drifting is done along a certain line, and they have to clip apexes, which are either geometric (the classic apex, in tighter turns) or the last apex (in fast sweepers, where the drivers go straight and dive into the corners very late).

Some drifters just let the wheel "do the job on it's own", as the slide creates an aligning torque that turns the wheel into the right direction. It's recommended, however, to try and turn the wheel with your hands. You perform a hand motion and than, if required, let the wheel "carry on" from that point and than grip it again.

The basics of left foot braking
All this talk of sliding in rallying and drifting made me recall left foot braking. I stated earlier that it's possible to brake with the left foot when the corner ahead does not require a downshift (and thus does not require rev matching), to shave off the precious tenths of a second when you leap from pedal to pedal. However, this should be distinguished from another type of left foot braking, called "combined braking." This is a kind of braking which is legitimate in moderate-speed corners on the track, and used even more extensively on rallying and in drifting. Instead of braking and applying gas apart, you apply both together.

This allows to manage the weight transfers of a car, mainly a drifting car, more accurately and immediately. It allows to maintain valuable engine force while braking, in turbo-charged engines that would otherwise suffer from turbo lag after letting go of the gas. In drifting, you can use the left foot to slow down while keeping the throttle on to keep the car sliding sideways.

The basics of competitions
The drivers go off onto the track from the "pits", and lap the track to determine their poll position, from which they than start in the actual race. In the race, drivers will seek to overtake one another. Overtakes are performed either by out-braking an opponent (braking later coming into the corners) or by taking a tight, inside line through the corner, forcing the driver on the racing line to let you complete the corner.

The communication on the track is based on weaving various flags from marshals posts along the track, from the starting point or from the control tower. The same flag might have a different meaning depending on where it is posted. The racers communicate by use of turn signals and hand gestures.

The basics of making it back home
A good race driver should acquire the proper skills for road driving: When I teach racers, I want them to live to race another day, and also -- proper road driving can help them A LOT in making the proper driving technique into a habit, and to save money that would otherwise be used on fuel, repairs and collisions -- on racing. The additional subjects of road driving include:

- Maintaining focus and clear mind through avoid distractions, alcohol and not sinking into deep thoughts while driving.

- Maintaining a proper following distance from other cars in front, alongside and even behind you.

- Taking proper lines (lines for road driving, not for racing) on bendy roads.

- Looking up ahead to the distance to make the driving planned and the "surprises" anticipated.

- Matching the speed to the road conditions and to the speed of traffic, including in traffic jams.

- Trying to monitor the traffic behind and avoiding being rear-ended

- Proper behavior when stopping in dangerous places, and when driving in intersections, interchanges and various kinds of roads.

- Practicing courtesy to other drivers

All of these points and others are detailed in my former posts and threads.
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ellaboswell
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Joined: Apr 29, 2011
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Location: USA

PostPosted: Wed Jun 15, 2011 12:25 am Reply with quote Back to top

Its really nice and huge information. Thank you for sharing.
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