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Posted

Hi folks,

Looking at the Altezza vid in the Altezza forum reminded me of something I've been meaning to ask for a while. Does anyone here use heel-toe while downshifting? Is it worth practicing for a lazy lazy man like myself? Is it really necessary to double-clutch, or is it sufficient just to keep the clutch in for the duration of the manoeuvre?

Si

Posted

I do both - but only because its fun! :D

Double clutching is always useful when going up hill, especially since the IS is so heavy. I do use a bit of heel-and-toe aswell, but only when I'm giving it some stick. Its a little difficult to do though in the IS because the accellerator pedal is so much lower than the brake.

Posted

I hardly ever use it during normal driving, but it can help to make your gearchanges smoother coming up to roundabouts or junctions.

Posted

Being trained by the fine DSA, I don't know what your on about. :blush:

Could somebody explain what Heel-Toe action is? :D


Posted
Being trained by the fine DSA, I don't know what your on about. :blush:

Could somebody explain what Heel-Toe action is? :D

Hey i still dont know what double clutching is..... :duh:

Is it when you're in a gear and in stead of dropping a gear you just drop the clutch again in the same gear :question::hehe:

Posted
Hey i still dont know what double clutching is..... :duh:

double clutching is dipping the clutch, and taking the car out of gear, followed by dipping the clutch (usually with a blip of throttle to match revs to the gear) and engaging the next gear.

pointless in modern cars - the syncromesh does this for you.

Posted
Hey i still dont know what double clutching is..... :duh:

double clutching is dipping the clutch, and taking the car out of gear, followed by dipping the clutch (usually with a blip of throttle to match revs to the gear) and engaging the next gear.

pointless in modern cars - the syncromesh does this for you.

Thankyou Matt :D

Posted

double clutching has nothing to do with heel and toe....heel and toe is a completely different driving technique

Posted
double clutching has nothing to do with heel and toe....heel and toe is a completely different driving technique

What i meant was i dont know what either are :blush: But i do know that they aren't the same thing

Posted
Being trained by the fine DSA, I don't know what your on about. :blush:

Could somebody explain what Heel-Toe action is? :D

How To

Heel and Toe Downshift

By Brent Romans

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 ***** 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?

:D

Posted
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.

Who does this? Go around a corner with the clutch in? You press the clutch and change gear straight away and with the electronic throttle on the IS the revs don't drop away too quickly.

As for powertrain wear, transmission these days can go well over 100k without having to heel and toe.

and what this that rubbish about safety? Safety is about being in the correct gear not how you get there by blipping the throttle.


Posted
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.

Who does this? Go around a corner with the clutch in? You press the clutch and change gear straight away and with the electronic throttle on the IS the revs don't drop away too quickly.

As for powertrain wear, transmission these days can go well over 100k without having to heel and toe.

and what this that rubbish about safety? Safety is about being in the correct gear not how you get there by blipping the throttle.

you got to read it all colin ;)

the next sentence says he is doing it wrong

frank is an example

it then goes on to say "the racers answer " is heel and toe

so i guess its not meant for the everyday road driver

Posted

I meant what everyday driver goes around the corner with the clutch in? I guess he means everyday American drivers?

Posted
I meant what everyday driver goes around the corner with the clutch in? I guess he means everyday American drivers?

an everyday american wouldnt know what a clutch is, let alone a corner :lol:

Posted

Isn't it double de-clutching?

Some racing cars have special pedals where the accelerator curves round the brake pedal. Some road cars have the accelerator closer to the brake.

Shouldn't need it with synchromesh.

Posted

The IS seems to be really badly set up for any heel toe action IMO, the accelerator pedal is set quite low and distant from the brake, the engine is lazy and not really blip-able.

You would have to give it quite a lengthy stab to get the revs up :unsure:

Posted
Isn't it double de-clutching?

Some racing cars have special pedals where the accelerator curves round the brake pedal. Some road cars have the accelerator closer to the brake.

Shouldn't need it with synchromesh.

Not really, its continuing to use the gas pedal with your toes while braking with your heel, for rallye style cornering. It enables better synchronised downshifting while braking (double clutching or not), and it makes for a quicker corner exit, even more so as the turbos are then spooled up already.

RX-Men-8

Posted
Being trained by the fine DSA, I don't know what your on about. :blush:

Could somebody explain what Heel-Toe action is? :D

I was about to ask the same question till I got to your reply

hope that make you feel better

Posted
whats the point of double clutching????

Basically, its so you can drop a gear and get a smooth gearchange. Say you are going up a hill, the car is slowing down and you need a lower gear to make it. Instead of dropping a gear and immediately flooring it (will result in a jerky gear change) you blip the throttle to rev match the new gear with the same speed you were doing in the previous gear. If you do it quick enough and know what you are doing you can do it perfectly and not even feel the downshift. Its the same with the heel and toe, if you do it right and match the revs properly, you can get a gear change and not even feel it, then get back on the throttle quicker.

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