I’m sure many of you are familiar with the term heel-toeing, but some of you may not know that it serves a purpose (other than to impress your passengers). One of the most important skills you need to learn as a high performance driver is how to manage weight transfer/tire load. As I’m sure you remember from last week’s article, tire load management is very important due to a tire’s non-linear lateral grip to normal (vertical) force relationship. When threshold braking (when the car is producing the maximum amount of braking force without locking up the tires), it is very important to be smooth. Any weight transfer during threshold braking can lock up tires which can induce a spin, or cause you to not make the turn (after all, a locked up/sliding tire has a much lower grip potential than one that remains rolling). When you downshift by simply letting the clutch up slowly (which is how everyone is taught to drive initially), you cause a weight transfer and change the attitude of the car. This unweights the rear tires (which can cause them to lock up) and transfers weight to the front (which could potentially cause them to lock up since you could very well be at the limit of the front tires load capacity). Heel-toeing, if done properly, will eliminate this weight transfer and will allow you to threshold brake and maintain control of the vehicle by matching the engine RPMs to the transmission speed of the next lowest gear. Heel-toeing is a simple concept and will eventually be second nature for you, but it requires practice. Lots of practice. Practice every time you come to a stop light, or are slowing for your exit on the highway (don’t practice the threshold braking part though, that could be bad). Your first track day isn’t the time or place to be experimenting with heel-toeing. Here’s a simple step by step of how to heel toe:
- Firmly and quickly apply the brakes (without “slamming”) until the threshold is achieved (this will also take some practice, but eventually you’ll be able to detect when the tires are just about to lock up)
- With the brake pedal still depressed, engage the clutch pedal and select the next lowest gear (Don’t skip gears as this creates a large difference in RPMs which can make the maneuver unnecessarily challenging).
- Now pivot your foot on the brake pedal while (maintaining a constant brake pressure) so that it makes contact with the gas pedal and give the gas pedal a quick jab or “blip” while letting the clutch up. you don’t actually have to use your heel for this either. If your foot is big enough, you can do what I like to call big toe-little toe (which is demonstrated in the graphic and video below). if done correctly, you shouldn’t feel any weight transfer at all and the shift should be perfectly smooth. The amount of blip you give is different in every car, and is something you’re going to have to get used to and feel out.
Check out the foot cam in the video of Mike Smith at Watkins Glen below to get a sense of the timing/rhythm of this technique.