Heel-and-toe

Heel-and-toe

Heel-and-toe is a driving technique used mostly in performance driving [http://www.nasaproracing.com/hpde/heelandtoe.html] , although some drivers use it on the road in everyday conditions in the interests of effectiveness. It involves operating the throttle and brake pedals simultaneously with the right foot, while facilitating normal activation of the clutch with the left foot. It is used when braking and downshifting simultaneously (prior to entering a turn), and allows the driver to "blip" the throttle to raise the engine speed and smoothly engage the lower gear.

Usage

Heel-toe or heel-and-toe double-declutching is used before entry into a turn while a vehicle is under braking, preparing the transmission to be in the optimal gear to accelerate out of the turn. One benefit of downshifting before entering a turn is to eliminate the jolt to the drivetrain, or any other unwanted dynamics. The jolt will not upset the vehicle as badly when going in a straight line, but the same jolt while turning may upset the vehicle enough to cause loss of control if it occurs after the turn has begun. Another benefit is that "heel-and-toeing" allows you to downshift at the last moment before entering the turn, after you have started braking and the car has slowed, so the engine speed when the lower gear is engaged will not be too high.

Performance vehicles are usually modified (if necessary) so that the heights of the brake and accelerator pedals are closely matched and the pedals are not too far apart, to permit easy use of heel-and-toe.

The name, stemming from earlier automotive designs where the accelerator pedal was on the left and could be actuated with the heel while the brake pedal was actuated with the toe, is misleading regarding how the technique is carried out in modern cars, i.e., operating the brake with the left edge of the foot, while rocking it down and to the right to operate the throttle. With practice, it becomes possible to smoothly and independently operate both pedals with one foot. The technique is common in all forms of motorsport, especially rallying.

As the power band of most rally cars is high in the rev range, this technique can also be used to ensure that engine rpm does not drop below the power band of the car while under braking. If this happened there would be a delay between the driver accelerating after the corner and when the car responds; this is especially true in turbocharged cars. This technique ensures that maximum power can be reached the instant the brake pedal is released and the accelerator fully depressed.

Procedure

:"Note: This description details a double clutch heel-and-toe downshift maneuver. If the gearbox is synchronized, the driver can omit the double clutch part."

When a driver performs a heel-and-toe downshift, they will first use the "ball" of their right foot (toe) to depress the brake pedal and slow the car down sufficiently. When the car is at the appropriate speed, the driver fully depresses the clutch pedal, cutting the power from the engine to the gearbox, and now shifts to neutral.

After that, the driver releases the clutch and rotates their right foot to operate the throttle with the outside edge of their foot (heel), increasing the engine speed to match the required rpm for the selected gear. Then, the clutch pedal is depressed and the correct gear selected from neutral, the clutch again released, and the engine connects to the gearbox once again.

Finally, the driver places the right foot back onto the accelerator, releasing the brakes.

On cars where the brake and accelerator pedals are very close together (as is the case with many racing cars), it is not necessary to rotate or twist the foot: the (right) edge of it may be used to "blip" the throttle, with the ball of the foot being suitably offset on the brake pedal.

It is worth noting that shifting to neutral may not be necessary. The driver can blip the throttle when the clutch pedal is depressed, then shift to the lower gear and release the clutch. While a modern synchronized transmission does not require double clutch shifting, a driver may choose to perform it in order to lessen wear on the synchronizer.

Alternative heel-and-toe technique

Utilizing natural human body mechanics, an alternate heel-and-toe technique can be used. In this method, the right foot is splayed out, with the heel control the brake pedal, while the ball of the feet near the little toe control the accelerator. It is much easier to rotate the toes from the feet outwards away from each other than the reverse, the feet can flex much more from the ankle, while the braking can be modulated by flexing the knee giving a much more extended range of control for the brake and accelerator pedal.

With practice, one can quite easily apply, modulate and hold the duration of braking and engine revolution as often, or as far and long as wished simultaneously. The flexibility of this method, apart from sporty driving, can be quite useful for creeping or stop-starts on up or down steep slope from a dead stop with total control and finesse. One simply flex the right toes for exact amount of engine revolution, ease off the clutch with the left foot at the same time as relieving the pressure on the brake pedal under the right heel and move off. No hand/parking brake assist is ever necessary, and with virtually no rolling of vehicle.

Note

An unrelated technique, called left-foot braking should not be confused with heel-and-toe.

External links

* [http://www.edmunds.com/ownership/howto/articles/45792/article.html Edmunds HOW TO with photos]
* [http://www.drivingfast.net/car_control/heel_and_toe.htm Heel and toe shifting explained with illustrations]
* [http://videos.streetfire.net/video/c8710573-fd48-4c11-8a2f-80db3f41d4d1.htm Video showing Gary Sheehan Heel And Toe Double-Clutching]
* [http://www.eurotuner.com/howto/38238/ Heel toe shifting for Auto Cross]
* [http://www.youtube.com/watch?v=cPj9XXW25GA YouTube instructional video]

References

* "Speed Secrets: Professional Race Driving Techniques" by Ross Bentley - ISBN 0-7603-0518-8
* "Secrets of Solo Racing: Expert Techniques for Autocrossing and Time Trials" by Henry A. Watts - ISBN 0-9620573-1-2


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Look at other dictionaries:

  • heel and toe — With strict walking pace, as opposed to running (also intransitive verb to use the heel and toe of one foot to operate both the brake and accelerator pedals, eg when driving a racing car) • • • Main Entry: ↑heel …   Useful english dictionary

  • heel-and-toe — heel′ and toe′ adj. of or designating a pace, as in race walking contests, in which the heel of the front foot touches the ground before the toes of the rear one leave it • Etymology: 1810–20 …   From formal English to slang

  • heel-and-toe — [hēl′ən tō′] adj. designating or of a walking race or jogging step in which the heel of one foot touches the ground before the toes of the other leave it …   English World dictionary

  • heel-and-toe — I. | ̷ ̷ ̷ ̷| ̷ ̷ adjective : marked by the alternating use of the heel and toe a heel and toe dance routine specifically : marked by the use of a stride in which the heel of one foot touches the ground before the toe of the other foot leaves it… …   Useful english dictionary

  • heel-and-toe — adjective Date: 1827 marked by a stride in which the heel of one foot touches the ground before the toe of the other foot leaves it < heel and toe walking > …   New Collegiate Dictionary

  • Heel and Toe Films — is a TV and Film production company run by Paul Attanasio and Katie Jacobs located at the address of 2058 Broadway, Santa Monica, CA 90404.The Heel and Toe films advert can be seen at the end of House, in which a foot comes down and crushes a… …   Wikipedia

  • heel-and-toe — /hil ən ˈtoʊ/ (say heel uhn toh) adjective 1. denoting a pace, as in walking contests, in which the heel of the front foot touches ground before the toes of the rear one leave it. –verb (i) (heel and toed, heel and toeing) 2. to operate the… …  

  • heel-and-toe — /heel euhn toh /, adj. noting a pace, as in walking contests, in which the heel of the front foot touches ground before the toes of the rear one leave it. [1810 20] * * * …   Universalium

  • heel and toe — A driving technique where the driver places the left side or the toes of his right foot on the brake pedal and the right side or the heel of his right foot on the throttle pedal so that he can simultaneously brake and blip the throttle for a… …   Dictionary of automotive terms

  • heel-and-toe — slow walk, stroll …   English contemporary dictionary

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