Cornering

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Driving in a straight line is easy, regardless of speed and conditions. However, cornering is where it gets harder, and that's why the concept of cornering, is 90% of racing.

Note: This article is accompanied with links to articles and videos that support the information presented herein, or supply the reader with further information, and possibly with necessary visual illustrations. They are typically short and catchy essays, so make sure you read them. If they are inconsistent with some of the content presented herein, the text in trackpedia takes precedence.

Contents

Road handling, road holding and cornering

When cornering, the terms "road holding" and "road handling" suddenly come up, and are often confused: road holding divides into two concepts, which are also sometimes mixed-up:

  • Grip: The term grip refers directly to the size and compund of the tire's contact patch. This concept is not static, and is effected by weight transfer and suspension geometry. Do further reading to understand the concept.
  • Adhesion: The tires' grip is used to generate a force called adhension. This force has to keep the car on the road surface, while also

generating the different applications: acceleration, deceleration (braking) and sideways movement (steering). Adhesion used for acceleration is called "traction". To get a better grasp of the this concept, read here.

Road handling is the result of the combination between road holding and car balance while cornering. Cars will handle at different ways according to drive train, chassis build-up, suspension geometry, tires and driving situations. Cars will tend to Understeer, oversteer or neutral handling.

A car has a generally small amount of grip. Each tire has a patch no bigger than a shoe, and this patch gives you a limited amount of adhesion, which is divided between several applications: steering (lateral), braking and accelerating (longitudal). Using all of the adhension you got for the sake of a single application is easy enough, but in cornering, even if you do try and segregate the actions as best as possible, there will always be more than one force working on the car. That's because, if we consider grip itself to be a "force", we also have the "centripetal" force (commonly called "lateral", and often mistakened with a "centrifugal" force), which is the inertia of the car from the straight road before the corner. This is what is measured in G-Forces. Additionally, a car can never work on steering alone. Cruising means deceleration, while any throttle application is considered acceleration, even if the car is not actually speeding up.

When driving in a straight line, reaching the limits of grip means reaching the limit of acceleration or deceleration, which are longitudal forces, who works parallel to the direction of travel. While cornering, reaching the limit of grip means reaching the limits of steering, which is not parallel to the direction in which the car wants to go, meaning, that the car will not make the turn. It might be pushed away from the turn head-on (understeer), or might do so with it's rear axle (oversteer). In both cases, the result will either be a slow lap time or, in a worst case, a wipe out.

Even more so, in a race, to differ from road driving, the car is always fully exploiting some 90% of it's grip at least. If control is indeed lost, even for a moment, recovery will be near impossible, regardless of the driver's skill. It's not a question of techniques and skill, it's a question of having any extra adhesion left to work with, which is a commodity you might be short of. The first rule of thumb is therefore: "Slow in, fast out".

For a bit of extra information about "slip angles", read This short article.

Cornering drift

On the track, the fastest way around is done without going sideways. In fact, the fastest cornering is done when the car is only slightly slipping, but not actually drifting around the corner. However, there are cases where a bigger Drift angle is actually required. If you are competing in an autocross or rally stage with corners that are very tight and sharp, over a slick surface and in a driftable car, you might consider sliding your way somewhat through the more narrow corners. Note that this is only a small, almost momentary, and very controlled sort of drifting. The driver still tries to be an neat as possible and follow specific lines. For this end, several techniques were developed:

1) Dynamic drifting: Used in moderatly sharp corners: The driver turns into the corner hard, lifts-off of the power to induce a slide, and re-introduces power to arrest the slide. With modern WRC cars, this alone can be enough to negotiate some of the hairpins.

2) The Handbrake turn: Used in the tighter and sharper corners. In Rally stages, for instance, it's usually something you cannot drive around because of the steering ratio of the car. This is normally a hairpin, but can also be a very sharp 90 degree corner. It should be stated that this is usually combined with power lift-off, so the driver lifts-off of the throttle, steers and handbrake his car simultanously.

In the WRC, these actions are perfected with the following techniques:

  • Apel contra Apel or, more percisely, a "scandinavian flick" or "double slide". The driver quickly flicks the car, steering slightly away from the corner, and than immediatly steers hard into the corner. This was used in front-wheel drive rallies in Finland, in conjunction with both power lift-off and, sometimes, with the handbrake turn, but is far less used in a modern WRC car, to differ from autocrossing.
  • Left foot braking: By using left foot braking, the driver can perfect the dynamic slide, handbrake turn and double-slide, by feathering the brakes into the corner, instead of merely lifting off of the throttle. This enables more speed to carried into the corner, and for more control through it.
  • Straightening the wheel early: In the speed and slick conditions of gravel rallying (to again differ from regular autocrossing), the driver can straighten the wheel before he induces the slide. This way, the slide is more controlled and the wheels are immediatly lined up to accelerate out of the corner. Keep in mind that, as far as intentional slides are concerned, any countersteering beyond the point where the wheels are straight means you are driving slow. The driver turns in agressively and excessively, than takes off most of the lock, and only than does he lift-off of the power. The same is done in a 90-degree handbrake turn (unlike the traditional handbrake turn through a hairpin). In the scandinavian flick, the driver turns away from the corner, turns into it hard, takes off the lock and than brakes moderatly. He might consider braking all throughout if the car tends to understeer. This should be distinguished from the "pendulum turn", where the brakes are fully stabbed for a moment, and the "feint" where the driver does the flick quite earlier.

The racing line

Look here and there before reading. Don't worry, it's short articles with visual illustrations.

A method of improving cornering is to make it as close to driving straight a head as possible. It's a common tendency to turn sharply (sticking to the inside of the corner) to make a shorter way through the turn, or to turn wide (sticking to the outside of the corner), to apply less steering input. The best approach is, therefore, a hybrid of the two: you reach the corner from the far end, steer into the inside of it, and exit again from the outside -- outside plus inside plus outside equalls: The racing line. The idea is to utilize the whole width of the track, not only it's length, and therefore turn the car at a wider radius that that of the corner, ideally "cutting" the corner is a straight line. This is the basic of every corner. However, in successive corners or in tight or sharp corners, this line might be slightly changed. First off, it can usually be refined by turning in a bit later. This might allow less stability going in, but will more stability going out, thus enabling to apply the power more early. A key point in this, is eye sight. You should be able to see most of the corner at the point of turn-in.

The central-inside part of the corner is the clip of the corner, also called the APEX. This should be separated from the "Clipping point", which is the actual point where you touch or near the APEX. It is vital that, as you approach the corner, that you see the turn-in and the APEX, and than focus on it. Once turning and about to approach the APEX, change your focus and look further ahead, as far as you can see, from the turn hence forth. This is important because this marker points: the turn-in, the APEX and the exit, enable to seperate the corner into three parts:

  • Approaching the corner: With the first rule of thumb being "slow in, fast out", almost every corner is preceded by a considerable distance known as the "braking zone". In this road section, the driver is using his brakes to slow the car down quickly and controlably, in order to reach a good access speed to enter into the corner with. A common mistake, is to brake too lightly to begin with, or too late. This can be improved again with the eyes. To begin with, mark a point to start braking. later on, you can learn to alternate your focus on a point in which most brake pressure is already released (brake-ending point, the turn-in point). Than, the rest is done by practice in techniques, predominantly threshold braking and heel and toe, which will enable you to exert maximal braking effort, and thus leave your braking later on. This technique is not too easy to master. One problem is that drivers are being "too smooth" with the brakes, squeezzing them down progressively. However, it is when the car is traveling faster (I.E. In the beginning of the braking procedure), that most of the braking effort needs to be applied. Therefore, the brakes should applied quite rapidly, almost stomping on the brakes, almost sticking them all the way down. A bit of squalling is natural and even a mometary lock-up of the front tires should not prove to be a disaster. From this point hence forth, the brake pedal should be under a constant and gradual release, whereas, by the end of the braking zone, brake pressure is minimal.
  • Turning into the corner: As you reach the corner, you need to release even more brake pressure. This is nessecary in order to minimize longitudal forces, allowing for more adhesion to be used for steering, and also to allow the dampers to de-compress and allow the wheels to travel smoothly across the road. Idealy, this part of the turn will actually fall into the first stage, whereas you would still be braking as lightly as possible when the steering is put in. This will create a forward weight transfer which will increase the grip of the front tires. From here, the car is turning through the corner, up to the APEX. Here, the demands on the tires and chassis are maximal, so the car must be either under light braking (trail braking) or under light power ("neutral throttle"). Idealy, the car should turn quite easily (Except on very sharp cornering with understeering cars). In fact, if done in maximal efficiency, the car's rear might feel a bit loose. At that moment, apply light to moderate acceleration while unwinding a bit of lock to induce neutral handling. In this case, the car should be slipping slightly and evenly on all four wheels, and steered with throttle application. ("Breathing the throttle").
  • Exiting the corner: As you are about to reach the APEX, you can begin acceleration, and as you enter and pass it, you may also undo the steering input. The more throttle you put in, the less steering you should have, ideally applying full throttle just slightly after the APEX while unwinding the wheel to a completly straight mode. Than, use every inch of the road as you run off wide. It's a common mistake not to run as wide as possible on exit.

This model has some modifications that can be put into it. As said, it's better to overlap the beginning of the second stage, by braking into the turn-in point ("Brake-Turning") or even through out the first half of the corner (trail braking). This allows for more adhesion to the front tires, and also enables you to keep your braking for slightly later. Another distinction, is which part is the most crucial? While the greatest demands are put on the car in the second phase, it's actually the third part, the exit, which is the important part. In most powerful race cars, gaining a few tens of a second throughout the corner by a fast entry (I.E. in the second stage), is not nearly as important as being able to exit the corner faster with the accelerator. That's why it's usually better to turn-in slightly later, Clip the APEX later and exit earlier. (a "Late APEX"). Read here to understand this concept better.

In very sharp corners (on the track, usually only a hairpin), on in a pair of corners in opposite directions or as a begginners technique used for safety (a slower turn-in and more visibility through the corner), a very late APEX (the "Last APEX") is used. The driver waits very late and than turns the wheel decisively and quite quickly into the corner. This line allows for fast acceleration out of very slow corners, or to remain on the inside towards the next corner.

One of the ways to sense a successful turn, is that the G-Force acts upon you similarly throughout the corner. At the same time, the steering lock should be put on from the turn-in to the APEX, and winded off progressively from the APEX and forth. The APEX point is the height of the centripetal force working on the car and, supposedly, the point where the car is driving a slowly as possible around the corner. Typically, it is possible to slightly cut the rumble line and even the track itselfat the APEX, as the inside wheels are fully unladen at this point. In fact, whatever little "drop" of the inside wheels will actually contribute to the car's stability through the turn. This should be avoided in faster corners, or with car that are problematic in that regard. Also, If the corner markers (rumble lines) are flat enough, and not excessively slippery, use them as part of the track. However, be careful with tall curbs, they can suck the car up and over them very quickly.

For more information and visual illustrations, read this and that.

On the track, following the trail set by tire marks could easily indicate the correct line. However, they cannot replace reference points for braking, turning-in, apexing and turning-out. Additionally, mobilized objects on the side of the road (rocks, etc...), or ones that are too far away from the side of the road will not suffice either.

Myths about the racing line

A note about some of the main rules-of-thumb we supplied you with:

  • Slow-in, fast-out: This rule does not apply to all corners alike: Trainees are too fast going into slow corners, but too slow going into the faster ones. Fast curves are often driven through at a very high speed. Furthermore, as skill progresses, one may try and carry speed into moderate-speed bends, especially if they are not followed by a long straight, or to maintain speed in between straights. This is one of the hardest things to do and some of the most infamous corners in F-1 tracks are such. Therefore, some very fast corners often do not require reference points for braking or even threshold braking!
  • Put the power down early: Sometimes, a good race is won by the driver who is later on the throttle rather than the ones early on it. Too early of an application of power might be very tempting or possibly "feel right", but will result in lost of grip and swerving from the line.
  • Use the whole width of the track: Often, it is not possible to use the whole width of the track, due to traffic, high berms and other factors. Often, in chains of corners, a drivers tracks-out or turns-in from the middle of the track rather than it's edges. There, a tighter line can often be faster than a wide line. In this case, if reference points are not available, one may use his steering wheel and engine and rhythm as reference points.
  • Limit braking: Sometimes, you do not need limit braking to slow down the car effectively, and a partial application is nessecary to avoid needlessly jerking the car. Additionally, braking later is not always faster: Any gains from braking late are going to be relativelly small, but it often results in unsmooth turn-in due to excessive braking. Additionally, the whole point about a rapid braking transition is intended to help you brake eariler and shave off precious tenths of-seconds at the brake-point by applying the brake rather firmly and by using the left-foot if a downshift is not needed.
  • Keep the car under drive: In some corners, in specific car specifications, one may coast into the corner without touching the pedals to reach a nessecary amount of a forward weight transfer.
  • Brake in a straight line: by trail braking we can brake into corners and delay the braking point in the straight further down. This way, we can actually brake through one corner to reach a second, slower corner, at an appropriate speed.
  • Minimize weight transfer: While it is important to keep the car stable and minimize the use of longitudal forces, certain corners will require a gentle utilization of weight transfer to negotiate a corner succesfully. This also dictates that a constant stress on driving smoothness is also not always appropriate and some hairpins or corners in corner sets require a very late APEX and decisive steering.
  • Eyes up: In a corner, simply looking far ahead is not going to be usefull. You will need to use reference points, and possibly look at a shorter distance to inspect your line. In this respect we should mention that sometimes not using a reference point for braking proves faster, and sometime another point is nessecary between the turn-in and APEX, and that sometimes such a reference point is not a point on the track.
  • Maximize grip through the corner: When driving through corners, it is important not to always maximize grip to the same extent. However, the fastest way around the corner is a slight slip.

Road angle vs. Turning angle

Sometimes, a corner is being made going slightly uphill or downhill, effecting the likelyhood of understeer and/or oversteer taking place in second phase of the turn. If going downhill, a great likelyhood of oversteer is possible. It's therefore best to turn-in early (Geometric APEX) and slower, with very little trail braking into the turn-in, by turning in while you are coming off of the brakes, or just at the moment when you lift-off of the brakes. If the car really tends to harsh oversteer quickly, you might consider turning in under neutral throttle. You can have more infomation on camber while cornering here.

Going uphill, weight tends to stay in the back, inducing more understeer. It's therefore important to go into the corner slower, at a late-APEX, turn the wheel more decisively while gently trail braking, and power-out progressively through the late APEX. If the car tends to understeer, you can use the Apel contra Apel method far more decisively and less smoothly.

Another scenario is for the road to have a Camber angle, that is, a slight side to-side slope. If the Camber is positive (a uphill slope towards the outer end of the corner), the tendency is again to oversteer, so an early APEX, with less (or no) trail braking and smoother steering is nessecary. However, if the Camber angle of the road is negative (Downhill towards the inside of the corner), a later-APEX, combined with trail braking and a sharper turn-in, is nessecary. If understeer occurs when cornering over a negative camber corner, use the Apel contra Apel technique more "brutally" than you would in a plain. If power-oversteer occurs, you may gently ease off of the power fully or almost fully.

Note that the way to do this is to look far ahead into the corner and through it, to recognise the angle of the turn. Read this brief article for more information.

Wet corners might also change your turning strategy. You need to take cleaner lines, and not use the whole width of the track (not hit the rumble area in the entry and exit, as it turns highly slippery. Look here for more information on this.

You will also need to consider blind spots around blind corners, problematic locations (bumpy road sections, small off-camber locations, water puddles, oil stains), and even tarmac quality and heat, and tire quality, state and temperature. And do not foreget to check your mirrors!

The road driving line

Apexing is not recommended on the road, unless done where the law, traffic and visual field allows it. However, typically, the driver will find that his visual field is obstructed just as he approaches the APEX. It's recommended to either follow the line of your lane, or possibly APEX within the bounderies of your own lane, or to use a wider line, which gives less centripetal effect and more visual field.

You can practice correct positioning and lines in winding roads, but do not exceed the bounderies of your lane, vision and do not drive near the limit, and without traffic around.

Additionally, since road driving should never be close to the limit, and that it's purpose is to reach a final destination, it's recommended to trail brake lightly, turn the wheel smoothly but not slowely (and don't turn-in hard), and react to road angles with the dosage of braking and turning speed, not with the corner approach (cornering line). If the car understeers, brake lightly or (if that's what you did), slightly increase brake pressure and than put on a bit more lock. If it oversteers, use one of two solutions:

  • Ease off of the pedals and focus on a visual target: This works with training.
  • Slam on the brakes while taking off the steering lock.

Heel and Toe can be done, even in automatics (although not recommended), but left foot braking is useless and not recommended. Threshold braking is also not nessecary due to approach speed, tire wear and traffic behind. If you want, there is more information about this in this article.

Corner classification

It's best to classify the different aspects of cornering, according to the different sorts of corners you can encounter. These aspects include: braking and access speed, turn-in (smooth vs. decisive), cornering (neutral throttle vs. trail braking), apexing (geometrical APEX vs. late APEX), understeer and oversteer corrections (pedalling vs. steering), visual field and etc. Each type of corner has typical beginner's mistakes and stresses.

Not all of these corners appear as frequently as others. Most corners are a medium-speed moderate bends, while a smaller amount of corners can be considered sharp. Almost every track has one or two fast curves, typically also an esses, and a hairpin or two, and several chikanes. Long, closing corners are less likely to appear.

The less severe is the corner, the higher is the access speed, the earlier is the APEX, the smoother is the steering, and the less trail braking is nessecary (if at all). The sharper the corner, the slower the acess speed, the later the APEX, the faster is the steering and more trail braking is nessecary. Sometimes, a driver can turn in early (a geometric APEX) and keep the throttle on (Power maintanance). In rare instances (really sharp corners) the driver has to take the latest possible APEX, turn the wheel almost sharply while trailing off of the brake.

When skill builds up, you will need to consider yet another factor in your cornering strategy, which depends not only on the type of corner, but also on the larger picture, of what is coming before and after the corner. The far most important type of corner in that regard is a medium-speed or fast, open corner, in between two long straights. Drivers with skill would attempt to maintain as much speed as possible from the first straight and into the second. Many of the most famous and notorious corners on F-1 race tracks belong to this category.

Open corners followed by short straights rely on mid-corner speeds, and can often very hard as well, however being of lesser importance in practice sessions. A third type is a corner opening or being a part of a corner set.

For visual illustrations of multiple racing lines, look here and here.

A fast curve

This is a small and flat curve or a fast esses or fast sweeper. It's the simplest form of a corner, yet also the most tracherous. The point of this curve being that, you approach it without significant braking, and go through it with light or moderate acceleration. If there is no need to downshift while braking before this sort of curve, you may consider braking with the left foot to reduce pedal transition time and return more quickly to the throttle, hence keeping the revs up. After the speed and gears have been matched, and the accelerator is threaded lightly or moderatly and the left foot applying pressure against the footrest, steer slowely and gently. The approach through such a curve is simply the most straight foward line you recognise with your eyes, typically an geometrical APEX (clip the curve at the percise, geometrical, center), without hitting the rumble line on the edge of the roadway, all while looking far out through the curve and past it. It's better in this case to turn too less rather than too much, and early rather than late, since you want to keep the car stable, because the direction of travel does not change. After the initial steering input, the arch through the curve, is better controlled by "breathing the throttle" application. Keep in mind that, in such a curve, slight and controlled understeer is better than any sort of oversteer. More throttle equalls more understeer (a wider arch), less throttle is less understeer (a tighter arch). Going off of the throttle equalls oversteer (a "too tight" arch), while going full on the throttle equalls a lot of understeer, but no slip.

Therefore, if the back-end does feel as if it's not gripping, do not hesitate and don't countersteer but simply thread the throttle quickly and quite powerfully, to allow the back axle to re-grip due to a rear-ward weight transfer. This works for all sorts of drives, as the engine cannot spin the wheel in such speeds (remember, alot of understeer, but not slip). The same applies for post APEX acceleration. As you are about to reach the APEX, increase throttle. As you are at it, you may put the power down quite quickly, almost stomping on it rather than squeezing it down.

A common mistake is to slow down and/or apply too much inputs of either steering, power or braking.

A fast curve is succesfull if taken smoothly, through the geometric APEX, with constant power and understeer allthroughout. This is also indicated by the wheel being turned-in smoothly and accurately, and turned-out just as it is turned in. In complex corner sets, a fast curve will normally appear in the begining, before a sharp or moderate corner, possibly requiring braking through the corner. Alterantively, it will appear at the end of the corner set. In this case, the fast curve is not considered part of the set as far as the line is concerned, because it is driven with the accelerator and in the geometric line. Meaning that your priority will be an early and fast exit from the turn leading to the fast curve. That is, a late APEX on the preceding corner.

An esses is a chain of small fast curves, through which the driver takes the most straightforward line. Notice that there might be a chance that a driver would have to brake through a fast curve or esses in order to negotiate a following sharp corner. This requires having the skill nessecary to brake mid-corner. More information can be found herein.

A moderate bend

This is a normal 90 degrees bend, typical of race tracks, taken in a moderate speed and steering inputs. Because of the speed involved (more than other benefactors of grip or weight transfer), the car must be made to turn smoothly through this sort of corner, with very little roll or weight transfer, which is achieved by driving smoothness and accuracy. It's important not to be slow with applications such as steering and/or power, but the stress here is 90 percent on driving smoothness.

Because of this, a lot of people tend to slip during this corner. It is also a great place for passing another car. Note that the approach speed in this sort of bend can is moderate, not slow neither fast, and can be improved if you feather the brakes into the turn-in. Than, turn the wheel as necessary, smoothly and in one fluid motion, but not too quickly, to avoid needlessly shocking the car. If you drive a rear-wheel-drive with a high tendency of oversteer, be even more gentle and smooth with your steering. You should get the car to turn in (idealy with a late turn-in) with light braking pressure (brake-turning, in some cars and corner setup maybe trailing-throttle: gently ease off of the throttle just as you turn the wheel) and than apply neutral throttle and apply acceleration as you reach the APEX, progressively accelerating and retracting the steering towards the exit. If your car and personal skills allow you to use trail braking and maybe Left foot braking, it might be advantageous if you brake before the corner with the right foot, and trailbrake through the corner with the left foot. Turn in as you can see at least most of the bend. Don't be afraid of slightly cutting the corner at the APEX, since the inside wheels will be unladen, and would easily take the hit.

If the car oversteers, use one of three methods:

    1. In the turn-in: Idealy, the rear of the car will feel "loose" as you turn-in, in which case you should simply go off of the brakes and maybe even accelerate slightly, while taking off a bit of lock. This can create a small percentage of neutral slip.
    2. In a rear or all-wheel drive: apply light throttle throughout while straightening the steering and possibly begining countersteering. As rear-axle adhnesion is regained, there will be a "pause" in the slide. Typically, the will be less pressure on the wheel at that point and the car will "bounce" back to straight, no longer being leaned sideways. At this point, take off the lock. Do not lift-off of the throttle.
    3. In a front-wheel drive: Get back on the power to a state of light acceleration while taking off a nice bit of lock, trying not to straighten out the wheel or turn it the other way. If oversteer is more acute, use more power rather than more steering. If you do countersteer, apply only a small amount of lock and quickly get it back off, with the foot keeping the car at a constant speed with neutral throttle.

If the car is understeering, you need to ease off of the power smoothly, and perhaps use the Apel contra Apel method of solving understeer. Understeer recovery is done smoothly and is based on more pedalwork than on steering.

Note: In moderate speed turns, car configuration details like softness, grip to-power ratio and weight take a greater consideration: A weaker car just might be better off driving through a geometric APEX, giving it more cornering speed, rather than a "fast" exit.

These types of corners are often more important than slower corners, since they are typically longer and therefore a greater sum of time is spent through them. Additionally, in such fast corners, there is a great requirement of percision, often leading to a potential risk of spinning or being overtaken, or simply losing speed and time, far more drastically than you would in a slower corner.

Common mistakes: a fast or early turn-in, turning in with too much braking or without braking. Early apexing.

A sign of success through this sort of corner is the feeling of a smooth ride.

Here's furher reading material.

A sharp corner

If in doubt, treat like a slow moderate bend. Here, the car must be forced to change direction completely and quickly. Therefore, you should begin with braking to slow down, typically more than what might feel right. It's better in this case to brake a bit early rather than late. According to the "slow in -- fast out" discipline, this corner entry speed should be down right slow, quite slower than what feels right. In sharp corners, almost all drivers, professionals and trainees alike, would have a quite similar access speed, since an any faster access is simply not possible, regardless of skill, or simply won't be beneficial. You need to wait for an APEX later than usual, and once you see through most of the corner, Turn into the corner decisively and quite quickly, while still staying just lightly on the brakes. Be accurate with the steering input, on the wet the car might respond with a slight "delay", but wait for it to turn without turning the wheel more. Generally, in a sharp corner, if in doubt, it's better to turn the wheel slightly more than slightly less. This corner is best approached with a very-late APEX. (Don't be afraid of hitting the rumble line and cutting the corner slightly!). In an oversteering rear-wheel drive, you need to be a bit more smooth. Anyway, let the car turn very tightly to line it up to the APEX and for acceleration. As you are about to reach the APEX (but before on it) start to accelerate and maybe begin unwinding the wheel. In this type of corner, trail braking from the turn-in to the APEX is recommended. The turn-in point is going to be alot further down the road than what is going to feel appropriate.

If carried out in maximal efficiency, the back-end might feel "loose" as you turn-in. At that fraction of a second, you can take off most of the lock while going off of the brakes and onto the throttle, you could make the car slide in a neutral state all throughout the corner, and control the arc of the turn with the throttle. This is the fastest way around this sort of corner. However, if the car does suddenly tends to oversteer, react in one of two ways:

1. In a Front-wheel drive: immediatly undo a nice amount of steering, trying to avoid countersteering or straightening the wheel completly, while getting back on the power, and than applying the throttle hard for a moment or two, and ease off to a very light application as the car seem to return to the desired line. The acceleration will transfer weight backwards and simultanously spin the front tires, to allow the centripetal force to push the front away, and back into the direction of intended travel.

2. In a rear or all-wheel driven car: Countersteer as nessecary, while applying a light to moderate throttle application. Once there is a pause in the skid, return the wheel to how it was before, slightly less tight. If the car is driven by all four wheels, you can now start to apply the throttle stronger.

If understeer occurs, use the Apel contra Apel method and be decisive and quick, rather than smooth, as in a more moderate bend. In severe cases, where the corner is very tight and sharp (and slick) you might want to consider to combine this method with a moment's worth pull of the handbrake. Take off a bit of lock while braking hard than ease off the brakes while reapplying steering ubruptly into the corner, than take off most of the lock and than nip the E-Brake for a moment. You need to keep the ratchet button on the E-brake depressed and the gearbox declutched. Than, set a gear, re-engage clutch and power out.

Note: Understeer in the first half of a sharp corner is typically caused either directly by excessive speed (to late a braking) or more typically by excessive braking into the turn-in, putting too much load on the dampers and too much adhesion demands on the tires. This, however, is also caused by excessive speed. The solution is, should this occur, to prefer braking that is a bit too early than too late (for sharp corners). Novice drivers make this mistake, but are inclined to believe they were running smoothly as they should. Alternatively, they might mistaken the phenomenon for a problem of car setup, which is far less likely. One sign is when the car is pushing in one or two particular corners, which can further suggest faulty driving technique rather than setup problems. If the issue does appear to be in the setup, start with the tires, and only if you are sure it's the car's alignment or dampeners which are to blame, begin readjustments. Don't swap a whole setup for one or two corners. A common mistake is to be too slow (or, alternatively, more sharp) with the steering. Additionally, drivers tend to believe that they are smooth, while actually being too tight or smooth, especially if adopting the early APEX, or one that is not late enough.

The sign of success through this sort of corner is that the car is not shaken, and that a very late APEX is being clipped. You can read more about this in here.

A hairpin

A hairpin, switchback or "U-Turn", is a tight 180 corner. In order to adopt the racing line into this corner, you need to brake it down into two corners, a bend and a sharp corner. Begin with a generally slow access speed, and run wide along the outside of the hairpin up to the center of the corner, trail braking into the corner, slightly tightening the line into the center of the corner as you go, but generally maintaining a wide line. The speed you carry into this phase of the corner should not be too fast, as you should tighten up the arc by 90 degrees soon enough. Now, you treat the second part of the corner as a seperate corners. Having said that it is the final exit speed that matters, get through this second corner by the racing line, preferably with a last-APEX. You should see the whole hairpin before you engage it. As you reach the hairpin, look for the geometrical center of the hairpin. At that point you should be on the far end of the centerline, and should see clearly through the rest of the corner or so, and than tighten up the steering while trailing off of the brake. Once the desired line is obtained, begin power application, from neutral throttle to light acceleration before the APEX and full power after the APEX.

If Oversteer occurs, you will have to ease off of the brakes and even accelerate moderatly to recover. In a RWD, you might need to countersteer and let the car slide a bit around the corner. If understeer occurs in the first half of the hairpin, it should be solved smoothly. In the second half, you can be far more decisive with your flick.

A common mistake is to turn-in too early, at the first half of the corner, or at the early APEX mid-corner (like a parabolic turn). Another mistake is to again believe you are going smooth, actually driving in a relatively jerky radious that constantly tightens-up, reaching the middle of the track half-corner, again leading to a too early turn-in.

The sign of success is again a relatively smooth ride and the clipping of the very late APEX.

Changing-Radius corners

This sort of long and progressive bends were found in old and big race circuits, and are thought to be the most challenging.

  • Increasing radius: This is a corner that is tight leading to the APEX, but winds-off as you exit. The idea is to approach the geometric APEX and accelerate as the road unwinds.
  • Decreasing radius: You should wait for a late APEX and use your eyes to see most of the corner as you turn-in towards the APEX.

Signs of success: A smooth ride and early acceleration.

For illustrations, see the HPDE Manual

Long bend

If the corner is long and tight, you should keep the car at the inside of the corner after apexing, while starting to gently apply power and exit as early and straightforward as you can. In all other respects, treat like a hairpin. A common mistake is to tighten up the steering too much.

Dual APEX

Approach in moderate speed. This is a long but progressive and smooth bend. While a tightening bend or hairpin are a combination of a bend and a sharp corner, this corner can be considered a combination of two bends. The driver should aim for a geometrical APEX, and exit to the outside centerline of the track, take the lock off while applying the footbrake sensitively, and than turn-in to clip a second, late APEX, running wide at the exit. It's a common mistake to think some dual-APEX corners for a single APEX corner. Indication of succes are simply a smooth ride.

You can read about dual-APEX corners here.

Successive turns

A real problem occurs when the driver needs to go through a complex of successive turns. The general idea here is usually to prefer a fast exit from the last corner, rather than a quick access to the first. This is called "corner prioritizing". You are not "sacrificing" corners, you are prioritizing!

To begin with, most of the braking should be done before the first corner, allowing to committ most of the braking in one time, rather than splitting it, even if it means going through one of the corners normally the first or middle one, slower than what you believe is possible, or in a slower line. This might also require braking through corners. Here, the driver has to be both decisive quick and almost "sharp", but still maintain the critical amount of smoothness.

In order to recognise the situation, the driver must see as much of the winding track to begin with, and than start dealing with each corner.

First off, if the turns are closely gathered, you might not always have the privilege of running wide exiting each corner, or of going through each corner using the racing line with the late-APEX. The main thing is that the last corner be taken in maximal efficiency, smoothness and be passed with as early full throttle as possible (late APEX). For this end, the first corners are taken either with an early APEX or a very, very late one, both giving the driver to option to stick to the inside of the track, allowing him to enter a following, opposite corner, from the far end of the track.

The steering should be made smoothly, but as quickly as nessecary. The tighter the corner, the quicker the steering. However, you need to minimize lateral weight transfer, so do not be as sharp as you would in a normal sharp corner. Note that if a situation occurs where the steering has to be rotated from one direction to the other quickly, you will need to pull it excessively in order to overlap the original steering input. In order to steer 90 degrees left and than 180 degrees right, you will need to place the left hand on 12O'Clock, pull 90 degrees, than place the right hand on the bottom of the wheel, with the palm and fingers pointing up, and pull it 270 degrees, to reach a 180 degrees left-hander.

Acceleration should be progressive.

If oversteer occurs, it must be resolved quickly and percisely. If you exit the left-hander (from the above example) with oversteer, do not turn right before making a full recovery. You may feel capable of doing it, but that thought may mislead you, as the second oversteer is due to be much harsher than the original slide (The pendulum effect). To correct oversteer, avoid counter-steering if it means pointing the wheel towards the edge of the roadway (with two successive corners in the same direction):

1) In a front-wheel drive: take off lock while nailing the throttle and spinning the front wheels for a moment and than regaining neutral throttle. If the conditions don't enable wheelspin under power, and there is not enough space for hard acceleration, use light acceleration, while taking off all the lock, and pointing the wheel just slightly where you want to go, according to the next corner. There might be a need to countersteer. In this case, countersteer with only a bit of lock, and immediatly straighten.

2) In a rear or all-wheel drive: Use a shallow countersteering angle with light acceleration.

If understeer occurs, you need to deal with it fast, with the Apel contra Apel method. Use it quickly, not as smoothly as you would in a more moderare bend, but not as sharply as you would in a sharp corner.

It's a common mistake to misjudge entry speeds and the lines, attempting to make it quickly through the first corner or set of corners on the expense of the later corner. It's also a common mistake to use steering techniques which require much hand-work, causing a much less accurate and less smooth handwork in this case, especially if you have acquired the habit of shuffling the hands. Also, pushing the wheel or relocating both hands over it, will force you to go through the center point when steering from side to-side and will also cause a lost of smoothness and awareness the angle of the front wheels.

The indication of success is a smooth ride and fast exit speed. Many driver are believe that they ran the corner set smoothly and quickly, while what they actually did was to carry speed into the first corner or two corners on the expense of a fast exit.

Here are a few examples:

Chikane

Chikanes are little twists on the track, sometimes also used in rally stages. They force the driver to make a successive left and right turn, thus forcing him to slow down. This is actually a safety tool, usually placed carefully before sharp corners or hairpins located just after a long straight road section. This fact is important to drivers too, since they should refer to the chikane according to what lays ahead and beyond it, and not just by the tightness of the chikane. To recognize this, you will need to take an initial view through the entire chiakne and past it. Than, you will need to recognize the turn-in and the two APEX points. The tighter the chikane, the shorter the gap between both APEX points. You will need to increase this gap, normaly by an early first APEX and a later second one.

A slow-in fast-out chikane

The driver prioritizes the second, faster part of the chicane by turning in very late on the tight portion of the chicane, lining up to take a normal, late APEX at the second turn. As you enter the chikane, you should look to the late second APEX and than the exit.

"A Slow-out chicane"

However, according to the location of the chicane in respect to other corners and straight before and after it, it might begin with a fast curve and than tighten up, allowing to carry a bit more speed into it and exit it at a slow speed with almost no regard to the entry speed. You should not go flat into it, so it's not a "fast in, slow out" chicane, it's just "slow out".

Brake as late as possible, and continue trail braking into the first portion of the chikane, which is negotiated at a straight, geometric line. Mid-way you can take off the steering lock and apply the brakes quite harder, and than turn into the second, and than turn late into the second part of the chicane and exit. You must keep as close possible to the left hand bend, possible riding on the second bend apex. However on the exit you have to wait for the car to straighten up before you can start to accelerate again.

If oversteer occurs in the chikane, you will need to release the footbrake and even apply light acceleration to stick the car to the road. If understeer occurs, you will need to do to opposite, and decrease acceleration/increase braking pressure, without turning the wheel even more.

The common mistake is to misjudge entry of the chikane, by speed and approach, making for a slower exit than possible, or to try running flat through the tighter chikanes.

Indication of success is that the car is not shaken through the chikane and exits it quickly.

Turn by-turn guides

See Also: Track Turn by-Turn guides

A race driving practice carried out in the Pisti track near Izmir, Turkey:

Here follows guide that will take you corner by corner through different tracks. Thier instructions might not be synchronized with the suggest approaches, but they are very good still. It's advised that you read at least one of these guides fully and comprehend them, for the sake of better understanding of the racing line through complex cornering sets.

You will find tons of guides under the "turn by-turn" guides article, but these are some of the most informative and important:


External links

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