Shifting Techniques

[Nick F40]

I've been talking with a member about this and he has given very well knowledgeable answers and I thank you, you know who you are but I was wondering from you guys about how the flat shifting/double clutching and heel tow works and how these two guys are different.

I know this might sound stupid but I want to know.

and double clutching

Edited March 19, 2008 by Nick F40

[CAL]

I've been talking with a member about this and he has given very well knowledgeable answers and I thank you, you know who you are but I was wondering from you guys about how the flat shifting/double clutching and heel tow works and how these two guys are different.

I know this might sound stupid but I want to know.

and double clutching

Actually all three of these vids show examples of toe/heel; however, their techniques are all a little different.

The last one the driver is quite quick and you may think you are seeing double clutching. I don't think I am seeing him double clutch.

Double clutching is would only be required when there is something wrong with the transmission or it's a bad designed. Something like that, where there is a drag between gears that doesn't allow them to synchronize. Or it’s a synchro-less trans. The double clutching is basically to slow down the natural “neutral†spinning of the gear the driver is going to shift into because no matter what to shift from one to another the gear speed needs to match.

Which has very little effect on the need for toe-heel driving.

I am sure if you have been in a discussion about it you understand that toe/heel driving is so that in a corner you can blip the throttle so that you don't spin in a corner. Think of the engine having braking power to. You don't want to much ie the engine at idle or near idle and down shift and let out the clutch, you will spin. You want to gradually let the engine braking power in and be able to control the rear of the car as much as possible with the trottle and not so much with the brakes.

Some cars are a lot more sensitive to this than others.

[Brendan]

The first video you show, he is mainly doing rev matching. He's kind of doing heel towing. He's not very good at it. If you listen to the sound, he's not matching the revs up very well. And if you listen to him he says he didn't want to do the heel towing in the corner and that's when you would be doing it. He is correct, though, on the first part in that you don't want to be using the clutch to slow it down. The thing is that most people don't drive fast enough to do damage to the clutch by engine breaking.

The second video shows a better example of heel towing.

The third video doesn't even show him double clutching at all. He's just down shifting very quickly. And blipping the throttle to keep the turbo spun up.

If you want to see someone who is an excellent heel tower, find a video of Boris Said. He's probably one of the best at it.

[ismaelg]

While not exactly an answer to your question, pro-drivers develop their own techniques and sharpen them with experience. For example, although a bit different scenario, Walter Rohrl did not use heel and toe but he was so fast with his feet it was like having a foot for each pedal.

Thanks,

Edited March 19, 2008 by ismaelg

[Nick F40]

Thanks for the input. I found a video on Boris and he is good. http://www.youtube.com/watch?v=ihCgxQnex5Q

While not exactly an answer to your question, pro-drivers develop their own techniques and sharpen them with experience. For example, although a bit different scenario, Walter Rohrl did not use heel and toe but he was so fast with his feet it was like having a foot for each pedal.

Thanks,

Yeah, I have that in my favs and was watching that last night. I think that that is insane, now he has the heel toe down very nicely. I would drive like that, it seems normal to me to use the left foot for braking and right for gas, I don't know, the other way seems weird, or maybe I am. I did notice that in the V8 supercars video,

he heel toed, flat shifted, and and used the clutch but stayed on the gas. I noticed that the honda racing video he really matched the revs.

Why does McQueen double clutch the 390 in Bullit?

Edited March 19, 2008 by Nick F40

[Brendan]

What you see in the Rohrl video is a technique called left foot braking. You see that a lot with front wheel drive cars and all wheel drive cars. You see him use the clutch every once in a while. What he's doing there is trying to break the back end loose when he's going around corners. The people that do road racing do more heel tow and the people who do off road racing usually do left foot braking. There are a couple of road racers who do left foot braking, but they usually have a background in rally racing.

[Nick F40]

What you see in the Rohrl video is a technique called left foot braking. You see that a lot with front wheel drive cars and all wheel drive cars. You see him use the clutch every once in a while. What he's doing there is trying to break the back end loose when he's going around corners. The people that do road racing do more heel tow and the people who do off road racing usually do left foot braking. There are a couple of road racers who do left foot braking, but they usually have a background in rally racing.

ahhhhhh, thanks Brendan. I guess I'm an offroad racer because it seem normal to me to use left foot braking. I have more control I guess. It all depends on if you want to break it loose or stick and get the rev match. Now, what happens if you don't rev match or do the 10/10 and don't time the clutchless shift right?

[dub]

Now, what happens if you don't rev match or do the 10/10 and don't time the clutchless shift right?

Your car spits out broken metal pieces!!!

[Brendan]

Now, what happens if you don't rev match or do the 10/10 and don't time the clutchless shift right?

Dub is right. I've been behind cars that have screwed up either downshifting or missing a gear and you get little gear pieces and oil spraying right at you. Another thing that happens is that the drive line sometimes snaps. But the worst thing that can happen is that you lock your transmission up. You hurt both the motor and the transmission.

[Nick F40]

Your car spits out broken metal pieces!!! :unsure:

haha ohhh, should have guessed that.

Dub is right. I've been behind cars that have screwed up either downshifting or missing a gear and you get little gear pieces and oil spraying right at you. Another thing that happens is that the drive line sometimes snaps. But the worst thing that can happen is that you lock your transmission up. You hurt both the motor and the transmission.

JEEZ

I still want to know why Steve double clutch's it or whatever he did in Bullit .

Edited March 19, 2008 by Nick F40

[Ron L]

I still want to know why Steve double clutch's it or whatever he did in Bullit .

I read someplace that claimed they dubbed in a GT40 race car sound in the double-clutch scenes, yet at one scene from a chase car view you can clearly see the exhaust puffs coincide with the double-clutching sound.

As to why he does it, I don't know. Because he's Steve McQueen and he can?