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Old 01-20-2005, 07:02 PM   #1
Sendero
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Heel Toe Braking (How to & Video)

Article by Brent Romans

Scroll to bottom for videos.

Quote:
If you have heard of the term "heel-and-toe" downshift before, but you've never known what it means, you've come to the right place. It is the mission of this article to make you a heel-and-toe master, a proverbial Jackie Chan of downshifts. Hi-yah!

A heel-and-toe downshift refers to a specific technique used to downshift a manual transmission car. It might seem bizarre to the general populace, but racecar drivers use it all the time. Once mastered, the heel-and-toe downshift offers the benefits of reduced vehicle wear-and-tear, better driver control and faster lap times on a racetrack.

The heel-and-toe downshift is a rather complex action involving both of the driver's feet, the driver's right hand, all three vehicle pedals and the gear shift lever. The purpose of the heel-and-toe is to smoothly match engine speed to wheel speed. Here is a generalization of how a normal person downshifts a manual transmission car.

Let's say Frank is driving his '01 Volkswagen Passat around town. He is approaching a right-hand corner while in fourth gear at 50 mph. He is going too fast to make it around the corner safely, so he starts braking until he drops the Passat's speed to about 25 mph. Frank sees on the tachometer that his engine revs are dropping too low, so he pushes in the clutch as he goes around the corner. As Frank thinks about accelerating, he realizes that the Passat is still in fourth gear, which isn't suitable for strong acceleration at such slow speeds. So he moves the shifter from fourth to second gear, lets out the clutch and motors away.

The problem with Frank's technique is that when he lets out the clutch, it is not going to be a smooth shift. The Passat is going to buck a little. Why? Because when Frank goes around the corner with the clutch pushed in, the engine revs drop to idle speed. When he releases the clutch, the mechanical locking effect between the engine and the front wheels (the wheels powered by a Passat) forces the engine revs to match the rotational speed of the rear wheels. In this case, 25 mph in second gear would mean the engine has to be at roughly 2,600 rpm. When Frank lets out the clutch after moving the shifter to second gear, his car's engine must instantly go from idle to 2,600 rpm. This sudden change causes the car to buck, as well as causing undue wear-and-tear on the clutch, transmission and engine mounts.

The simple solution for Frank would be to give the car some throttle before he lets out the clutch. Specifically, he should raise the engine speed to 2,600 rpm. This way, the engine speed is equalized to the wheel speed for second gear, making the shift much smoother. For racecar drivers, however, this technique is too slow and also means that when the car is going around the corner, the clutch is pushed in, a serious no-no in a racecar.

The racer's answer is the heel-and-toe downshift. The technique combines braking and downshifting at the same time. Using our example again, if Frank used a heel-and-toe downshift, he would have downshifted while he was braking for the corner. This way, he would have had power while he was going around the corner and he could have quickly applied more throttle once he exited the corner. These are critical elements to a racecar driver, but they can also be useful to any driver on the street.

Here is a step-by-step guide on how to heel-and-toe downshift. It will explain how to shift from fourth gear to third gear, though the technique will work for any downshift.


Begin braking for the corner with your right foot. The location of the pedals and the size of your foot will dictate where you position your foot on the pedal, but most likely it should be canted a little to the right, closer to the throttle pedal.


Push in the clutch with your left foot.


This is the hard part. With your right foot still applying pressure to the brakes, roll the outside edge of your foot outward and downward to touch the throttle pedal. The pedal design on some cars makes this easier to do than on others. Use the outside of your right foot to blip the throttle. Blipping the throttle means temporarily raising the engine rpms to match the wheel speed. The exact amount of revs needed is dependent on a variety of factors, but it is usually between 1,000 rpm to 2,000 rpm more than the current engine rpm for a one-gear downshift.


Move the shifter to third gear.


Release the clutch with your left foot.
As you can see, "heel-and-toe" is a misnomer. It actually involves the ball of your foot and the side of your foot. We'll be the first to tell you that heel-and-toe downshifts aren't easy. We've found that a good way to practice is to just sit in your car in your garage and pretend you are doing a heel-and-toe downshift with the engine off. Keep repeating the steps until you are familiar with the process. Once you are ready, try it out for real. Most likely, your early attempts will be botched. Keep trying, though. Practice each step slowly and then work your way to making them all one, fluid motion. Skilled drivers can execute a heel-and-toe downshift in less than one second.

The trickiest part is getting the correct amount of rpms to match the new gear. If you blip the throttle too much, the engine has too much speed compared to the wheels and is forced to drop down to the wheel speed when you let out the clutch. If you don't blip the throttle enough, the engine rpms are forced to rise up. Either way, you know you didn't do it right as the car will jerk a little.

You'll also know it when you did it right. A proper heel-and-toe downshift is so smooth and so satisfying that, once done correctly, you'll find yourself using the technique all the time. The great thing is that you don't have to be a racecar driver or be on a racetrack to use it. Additionally, using the heel-and-toe downshift technique on the street can improve safety. In certain emergency situations, you might be required to brake heavily and then accelerate quickly. By heel-and-toe downshifting, your car will be in the best gear to achieve maximum acceleration.

So, let's recap. It's fun to do. It improves driving safety. It reduces the amount of powertrain wear on your car. Other than the amount of time it takes to learn, there is no downside. What more could you want?
This is a good example of not only Heel Toe, but double clutching:
Team Sheehan

Everytime I watch this one, I keep waiting for Godzilla to appear!
Japanese Video (25mb)

Enjoy!
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Old 01-20-2005, 07:08 PM   #2
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Re: Heel Toe Braking (How to & Video)

Have you done anything to change the pedal positions in your car to help with H&T shifting? I've tried it in my car and it seems like the gas pedal just sits to low to the floor (or the brake too high, however you want to look at it). My feet are sort of medium sized (10.5 - 11, standard width) and I can't seem to make my foot reach both pedals at the same time.
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Old 01-20-2005, 07:12 PM   #3
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Re: Heel Toe Braking (How to & Video)

Quote:
Originally Posted by TheJeanyus
Have you done anything to change the pedal positions in your car to help with H&T shifting? I've tried it in my car and it seems like the gas pedal just sits to low to the floor (or the brake too high, however you want to look at it). My feet are sort of medium sized (10.5 - 11, standard width) and I can't seem to make my foot reach both pedals at the same time.
I practice my heel/toe on the street and don't notice the pedal problem.
Depends alot on which shoes you're wearing too. But I think you'd find that under hard braking(high pedal effort) your brake pedal and gas pedal would be closer together. You wont notice this on the street since you don't do racetrack type braking.
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Old 01-20-2005, 07:14 PM   #4
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Re: Heel Toe Braking (How to & Video)

Quote:
Originally Posted by Wicked
I practice my heel/toe on the street and don't notice the pedal problem.
Depends alot on which shoes you're wearing too. But I think you'd find that under hard braking(high pedal effort) your brake pedal and gas pedal would be closer together. You wont notice this on the street since you don't do racetrack type braking.
That's true. Under heavy braking it is closer, but it still seems like my pedals are too far apart. Maybe I just need to experiment with it a little more.
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Old 01-20-2005, 07:16 PM   #5
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Re: Heel Toe Braking (How to & Video)

Quote:
Originally Posted by TheJeanyus
Have you done anything to change the pedal positions in your car to help with H&T shifting? I've tried it in my car and it seems like the gas pedal just sits to low to the floor (or the brake too high, however you want to look at it). My feet are sort of medium sized (10.5 - 11, standard width) and I can't seem to make my foot reach both pedals at the same time.
I cut a nylon spacer to raise my gas pedal up to the level of my brake pedal. I'm looking at modifying the gas pedal lever to move it closer to the brake pedal. Some modify their brake pedal, but I don't feel like trying to recalculate motion ratio's for the Master Cylinder. I can't reach both pedals unless my foot is almost sideways on the brake.
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Old 01-20-2005, 07:17 PM   #6
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Re: Heel Toe Braking (How to & Video)

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Old 01-20-2005, 07:22 PM   #7
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Re: Heel Toe Braking (How to & Video)

Quote:
Originally Posted by Sendero
I cut a nylon spacer to raise my gas pedal up to the level of my brake pedal. I'm looking at modifying the gas pedal lever to move it closer to the brake pedal. Some modify their brake pedal, but I don't feel like trying to recalculate motion ratio's for the Master Cylinder. I can't reach both pedals unless my foot is almost sideways on the brake.
You wouldn't have to recalculate ratios, you'd only be changing the lowerend of the pedal. But anyway, I wouldn't mess with it. You have to cut and reweld the brake pedal arm somewhere below the MC connection.

You need a wider shoe, I never use the "heel" and "toe". I use the ball of my foot(big toe) on the brake pedal and the little toe side for the accel pedal.

Joseph, next time we are together lets compare pedals.
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Old 01-20-2005, 07:26 PM   #8
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Re: Heel Toe Braking (How to & Video)

Quote:
Originally Posted by Wicked
You need a wider shoe, I never use the "heel" and "toe". I use the ball of my foot(big toe) on the brake pedal and the little toe side for the accel pedal.
That's what I've tried to do, too. That's what Bob Bondurant recommends in the book he wrote on high performance driving.

Quote:
Joseph, next time we are together lets compare pedals.
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Old 01-20-2005, 07:26 PM   #9
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Re: Heel Toe Braking (How to & Video)

Wicked - the difference may not be in pedals, though. Judging by the fact that you're like 6" taller than me, you probably have bigger feet than I do.
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Old 01-20-2005, 07:27 PM   #10
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Re: Heel Toe Braking (How to & Video)

Quote:
Originally Posted by Wicked
You wouldn't have to recalculate ratios, you'd only be changing the lowerend of the pedal. But anyway, I wouldn't mess with it. You have to cut and reweld the brake pedal arm somewhere below the MC connection.
Thats not a part I want to take a chance on welding.

Quote:
You need a wider shoe, I never use the "heel" and "toe". I use the ball of my foot(big toe) on the brake pedal and the little toe side for the accel pedal.
I wear size 11 shoes. I can fit my Adidas training shoes between the brake and gas pedal. My AE boots barely touch each pedal and those things are snowshoes!
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"Never argue with an idiot. They drag you down to their level, then beat you with experience." -Unknown
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