Intro to “Heel and Toe”By Dale Willis Okay, so you are new to autocross or have just tried your first road course during a Driver’s Ed event at Firebird East or Pinal. You’ve found you can do most short autocross courses in second gear (depending on your car), but the longer autocross courses and the road courses require gear changes. Shifting up through the gears is no problem – you do it every day and a smooth, positive upshift is like second nature to you. Downshifting may be a little more problematic and a less than natural activity, however. A well-executed downshift allows you to smoothly enter and exit a corner in the proper gear to produce maximum acceleration in the next segment of the course. This requires mastery of what is called “heel and toe” technique, which will allow you to smoothly shift to a lower gear while maintaining maximum braking – without upsetting the balance of the car. Heel and “toe” downshifting is a misnomer --it really should be called “heel and ball” or “ball and side” (of the foot). Toes have nothing to do with it. The latter two terms are not as catchy, huh, so we’ll stick with the common name. You probably already know what happens when you don’t use this technique: You brake going into a turn, depress the clutch, downshift and release the clutch. The car nose-dives, the rear wheels lock up momentarily due to engine compression braking and, if you are turning, you may be in a spin. At the very least you’ve over stressed your drive train and engine and lost whatever momentum you had going into the turn. There is an easier way! It just sounds more complicated. Really! The objective of heel and toe downshifting is to match the speed of the engine with the speed of the gear you are selecting (think rear wheels) by -- while braking with the ball of your foot -- rotating your heel to stab or “blip” the throttle bringing the revs up to the appropriate level. What is the “appropriate RPM level?” Depending on your car it is usually several hundred RPM higher, but it is something you must develop by feel, by ear and by experience, not by watching the tachometer. Too much RPM and the car lurches forward, too little and the tires chirp and you nose-dive. Just right, and it is just like “buttah.” A smoothly executed heel and toe downshift is third on my list of “most fun things you can do with your clothes on.” It is important to remember that you should be using the brakes to slow down and not using the engine compression to slow. Using the engine to slow down makes brake modulation more difficult and upsets the balance of the car that you are trying to achieve through smoothness. Okay, I use engine compression all the time on the street to hear the burbling and popping of my exhaust, but it is not a good technique for the track. It is a good way to get a feel for RPM-matching on the street, however, while satisfying your sonic urges. (I feel sorry for you guys with quiet cars!) Now, when you try this technique you will probably find that your ankle is not flexible enough to get your heel down far enough to “blip” the gas pedal while the ball of your foot is on the brake. You don’t have to be a ballet dancer, but it helps! The solution is a minor modification to the throttle pedal to bring it slightly below the brake pedal when the brake is depressed. You can build-up the throttle pedal about ½ to ¾ of an inch several ways: There are commercially available replacement and clamp-on, adjustable throttle pedals (check Porsche Panorama and Excellence Magazine) for $100-150. Some versions have an extension below the brake pedal so you don’t even have to rotate your heel. A more economical solution is to purchase a conventional, stock throttle pedal and mount it to the existing pedal using spacers to suit. Care should be taken so the built-up pedal is secure and free in travel. What about that other heel and toe description I used: “ball and side?” The cockpit area on Porsches gets tight near the pedals and if you resemble “bigfoot” there may not be much room to maneuver your heel. An alternative technique is to slide your foot slightly to the right on the brake pedal so that ½ to 2/3 of the ball of your foot is applying the brake pressure. To blip the throttle, simply roll your foot so the right sole/edge of your foot pushes the throttle. Both techniques require some practice and, in each case, after blipping the throttle your foot should smoothly rotate to normal braking position. Just as in life, timing is everything. One challenge of heel and toe is to constantly maintain consistent braking pressure while your heel or the side of your foot is doing its thing blipping the throttle. Additionally, you can’t freeze and forget to quickly and smoothly release the clutch pedal while the RPM is up. Let the RPM drop and you are back where you started. While you are learning it may happen occasionally until you get the feel for the timing. When to downshift? At the approach to the corner just before you turn in – brake first and then downshift – to be in the proper gear and at the best RPM to maximize acceleration out of the turn. This will also allow you to concentrate on executing the turn without too many timing issues. However, you should work towards shifting at the last possible moment before turning in. To learn more about heel and toe downshifting and high performance driving in general, check out Secrets of Solo Racing by Henry A. Watts, High Performance Driving by Bob Bondurant and John Blakemore and Speed Secrets by Ross Bentley. If at first you feel frustrated, remember the advice given to the street-direction-seeking tourist when he asked, “How do I get to Symphony Hall?” The reply: “Practice, man, practice!”
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