what is this heel-toe stuff?
Discussion
Got to agree with Henry, H&T is all about matching revs, fail to do that and you're in the scenery. Its of course magnified in importance when its wet. I perhaps have mis read your reply but I don't understand your comment about it saving time...
Even with sequential boxes you still H&T sometimes...I watched with interest the footage from the pedal box camera in Pat Long's car during the last ALMS round...
There is always a story going around that such and such world champ never H&T'd. I always think that these stories on the whole are fallacies made up by those who can't master the most basic of techniques to make themselves feel better. If you've gone racing and you can't H&T take it as a sign that other sports beckon.
>> Edited by 27tim on Thursday 8th December 23:17
Even with sequential boxes you still H&T sometimes...I watched with interest the footage from the pedal box camera in Pat Long's car during the last ALMS round...
There is always a story going around that such and such world champ never H&T'd. I always think that these stories on the whole are fallacies made up by those who can't master the most basic of techniques to make themselves feel better. If you've gone racing and you can't H&T take it as a sign that other sports beckon.
>> Edited by 27tim on Thursday 8th December 23:17
You should note that the right foot cannot, while braking, be released from the pedal in order to actuate the accelerator for either part of the double-declutch procedure. It has therefore to do it at the same time, at the right moment, and in one movement. This action, known as 'heel and toe', is obviously aimed at saving time.
Alain Prost, Competition Driving
flemke, henry-f.
From what I understand you are both right!
Matching revs on the downshift eliminates the effect of "clutch-drag" braking on the drive wheels. This will help prevent drive wheel lock-up and is certainly good for the clutch. Main reason, however, is to prevent the lock up.
You could achieve all this by braking. Then coming off the brakes. Then dipping the clutch whilst blipping the throttle and selecting the lower gear. Then letting up the clutch.
This achieves the same thing - and is part of "The System of Car Control" as advocated by the Police, RoSPA, IAM et al.
In order to have time to do all these actions in sequence you would need to brake earlier to have time at the end of the braking for a subsequent downshift. This is fine on the road - its not a race!
In comparison to this heel and toe technique allows simultaeneous hard braking and downshifting rather than a sequence of braking then downshifting. Clearly whilst on a track this saves valuable time...faster lap times...race wins etc.
From what I understand you are both right!
Matching revs on the downshift eliminates the effect of "clutch-drag" braking on the drive wheels. This will help prevent drive wheel lock-up and is certainly good for the clutch. Main reason, however, is to prevent the lock up.
You could achieve all this by braking. Then coming off the brakes. Then dipping the clutch whilst blipping the throttle and selecting the lower gear. Then letting up the clutch.
This achieves the same thing - and is part of "The System of Car Control" as advocated by the Police, RoSPA, IAM et al.
In order to have time to do all these actions in sequence you would need to brake earlier to have time at the end of the braking for a subsequent downshift. This is fine on the road - its not a race!
In comparison to this heel and toe technique allows simultaeneous hard braking and downshifting rather than a sequence of braking then downshifting. Clearly whilst on a track this saves valuable time...faster lap times...race wins etc.
At the risk of furthering an increasingly pedantic thread, surely the whole point of the H&T is to prevent destabilisation of the car, regardless of whether it is severe enough to cause lock up? There is nothing stopping you changing gear whilst on the brakes with no H&T blip or coast, and indeed that is what many drivers do, so the time element doesn't strike me as the determining factor. I'm inclined to agree with Henry, that the main reason for the H&T is to maintain stability with the secondary benefit of engine braking which gives more rear brake bias.
There has been the odd mention of right foot braking. This is so different from H&T. If you have to change gear during RFB you do it without using the clutch. Not too difficult once you get the hang of it, but practice in a hire car. One of the main benefits of RFB is using the brakes and throttle together, this CAN have the effect of stiffening the suspension through mechanical lock and also helping traction (a poor mans LSD), only useful on loose surfaces, don't practice on the road!
AJAX50 said:
There has been the odd mention of right foot braking. This is so different from H&T. If you have to change gear during RFB you do it without using the clutch. Not too difficult once you get the hang of it, but practice in a hire car. One of the main benefits of RFB is using the brakes and throttle together, this CAN have the effect of stiffening the suspension through mechanical lock and also helping traction (a poor mans LSD), only useful on loose surfaces, don't practice on the road!
Don't you mean Left Foot Braking? You use the right foot for the throttle and the left foot for the brake.
I left foot brake all the time these days...
One (very useful) technique I have found to be good for dealing with tailgaters: very lightly depress the brake pedal with the left foot - brake lights light up - whilst simultaeneously stamping (ok gently squeezing) the accelerator...they see the brake lights, brake whilst you accelerate away. Confuses 'em no end and creates a nice big safety gap.
One (very useful) technique I have found to be good for dealing with tailgaters: very lightly depress the brake pedal with the left foot - brake lights light up - whilst simultaeneously stamping (ok gently squeezing) the accelerator...they see the brake lights, brake whilst you accelerate away. Confuses 'em no end and creates a nice big safety gap.
AJAX50 said:
There has been the odd mention of right foot braking. This is so different from H&T. If you have to change gear during RFB you do it without using the clutch. Not too difficult once you get the hang of it, but practice in a hire car. One of the main benefits of RFB is using the brakes and throttle together, this CAN have the effect of stiffening the suspension through mechanical lock and also helping traction (a poor mans LSD), only useful on loose surfaces, don't practice on the road!
Presuming you mean LFB? You can still work the clutch having LFB'd into a corner, but its a ridiculous pedal dance that I can't pull off despite having been shown how to do it. Dunno about the suspension stiffening aspect (sounds a bit odd?), but you can use it to provoke or correct oversteer without having having to use any opposite lock or when you've run out (provoke by trail braking whilst turning and using throttle, correct by locking the front wheels but keep the rears rotating to provoke understeer). All a bit too difficult for me to pull off anywhere but an empty airfield!
Don said:
I left foot brake all the time these days...
One (very useful) technique I have found to be good for dealing with tailgaters: very lightly depress the brake pedal with the left foot - brake lights light up - whilst simultaeneously stamping (ok gently squeezing) the accelerator...they see the brake lights, brake whilst you accelerate away. Confuses 'em no end and creates a nice big safety gap.
and let's hope they're not panic'd into braking hard and causing an accident!
Joe911 said:
and let's hope they're not panic'd into braking hard and causing an accident!
Well indeed. Let us hope so. However - if they do have a prang
1) It will be utterly their fault.
2) I will not be involved...
unlike the utterly foolish "brake test" manouvre which is asking to have 'em run into the back of you.
I should point out that when I use this little trick its in 30mph limits when I have no possibility of getting out of their way and simply letting them past - which is highly preferable. Nor does "illuminating the brake lights" mean I slow down at all (in fact the opposite - because I accelerate) so they've nothing to run into...its a slight extension of braking early and gently for any hazard to give the numpty behind lots of time to react so they don't run into you.
If simply seeing brake lights go on is enough to make a numpty panic brake and prang then they really, really shouldn't be on the road. My technique is designed to reduce the risk of a prang not cause panic braking.
DanH said:I think the assumption is that we always would try to match revs properly, regardless of whether the downshift is done during the braking or after it has been completed.
At the risk of furthering an increasingly pedantic thread, surely the whole point of the H&T is to prevent destabilisation of the car, regardless of whether it is severe enough to cause lock up? There is nothing stopping you changing gear whilst on the brakes with no H&T blip or coast, and indeed that is what many drivers do, so the time element doesn't strike me as the determining factor. I'm inclined to agree with Henry, that the main reason for the H&T is to maintain stability with the secondary benefit of engine braking which gives more rear brake bias.
The point is that you can always downshift after braking, so why would you do it during braking? You would do it to save time, as Prost says. If you have elected to do it during braking, then necessarily you would try to do it in such a way that minimises destabilisation.
H&T is how to correctly brake and downshift simultaneously. Why would you brake and downshift simultaneously? To save time.
Pedantry - isn't that what forums are for?
Kin ell - Never read such a load of twaddle in my life.
The papers on Monday are going to be full of "Bizarre Spate of Supercar Incidents across UK!"
I can just hear all those graunching gears, screeching tyres and the crunch of metal as Mr Nermal smacks into a left-foot braking afficionado (or was it right foot braking??? no - right foot on the clutch???? no - that can't be right! Ah wot the hell!!).
Please re-read Henry's post... Of course he's balancing the car keeping it nice and stable!
H&T is simply a method of braking, downshifting, letting the clutch out AND avoiding lock ups all at the same time!! Of course its saves time! Its a fekkin racetrack fer kerist sake not a WOTY!!!
And if you lot are going to practice on the highways and byeways please post here the intended roads and times so I can avoid them all!
pant, pant....
The papers on Monday are going to be full of "Bizarre Spate of Supercar Incidents across UK!"
I can just hear all those graunching gears, screeching tyres and the crunch of metal as Mr Nermal smacks into a left-foot braking afficionado (or was it right foot braking??? no - right foot on the clutch???? no - that can't be right! Ah wot the hell!!).
Please re-read Henry's post... Of course he's balancing the car keeping it nice and stable!
H&T is simply a method of braking, downshifting, letting the clutch out AND avoiding lock ups all at the same time!! Of course its saves time! Its a fekkin racetrack fer kerist sake not a WOTY!!!
And if you lot are going to practice on the highways and byeways please post here the intended roads and times so I can avoid them all!
pant, pant....
Don said:
Well indeed. Let us hope so. However - if they do have a prang
1) It will be utterly their fault.
2) I will not be involved...
I disagree.
While they may have been foolishly and dangerously tailgating you - it was your action that could have triggered an accident that may cause the death of several people - including (worst case) child passengers in the car behind (or the car behind that).
While their actions are foolish - to provoke a potentially unpredictable reaction at, for example, motorway speeds, is just lunacy - surely?
If I step off the pavement into the path of your car - and you could stop safely, but choose not to and run into me (because I am a dangerous fool for stepping into the road) - do you have a clear conscience (regardless of whether the police see you as at fault)?
>> Edited by Joe911 on Friday 9th December 11:28
Joe911 said:
Well indeed. Let us hope so. However - if they do have a prang
1) It will be utterly their fault.
2) I will not be involved...
I disagree.
While they may have been foolishly and dangerously tailgating you - it was your action that could have triggered an accident that may cause the death of several people - including (worst case) child passengers in the car behind (or the car behind that).
While their actions are foolish - to provoke a potentially unpredictable reaction at, for example, motorway speeds, is just lunacy - surely?
If I step off the pavement into the path of your car - and you could stop safely, but choose not to and run into me (because I am a dangerous fool for stepping into the road) - do you have a clear conscience (regardless of whether the police see you as at fault)?
>> Edited by Joe911 on Friday 9th December 11:28
Joe - either you are wilfully misinterpreting what I am saying or you have not understood it.
Joe911 said:
While they may have been foolishly and dangerously tailgating you - it was your action that could have triggered an accident that may cause the death of several people - including (worst case) child passengers in the car behind (or the car behind that).
Just a bit ThinkOfTheChildrenIst don't you think?
But in any case. I, as a road user, am entitled to brake and slow down as and when I please. I am entitled to speed up when I please. I am entitled to brake but not slow down when I please. And I am even entitled to brake and speed up when I please. It is the legal responsibility of the following driver not to run into me.
Notwithstanding this. It is foolish in the extreme to perform a manouvre that might precipitate an accident. I would never do such a thing. I already mentioned that in no case could this be construed as a "brake test" - an idiotic manouvre likely to result in an accident.
So. How can "lighting up my brake lights" whilst simultaeneously speeding up in a 30mph environment possibly cause an accident. It cannot. It is less likely to cause one than lighting up my brake lights and simultaeneously slowing!
I never mentioned motorway speeds - you did.
But now I will.
Let us say I have someone following at ten yards at 70mph. I am in a queue of traffic - there is no going anywhere - there is no changing lanes. I am leaving a decent distance to the car in front. I can slow if necessary. The guy behind cannot. What do I do? Well....
1) Increase the distance between me and the car in front of me possibly by braking a little, very gently. This means in the event of an incident up front and I can slow even more gently than usual giving the guy behind even more reaction time than usual to help compensate for the fact he is foolishly close.
2) Once a decent gap has built up to the car in front. I then left foot brake to keep the brake lights illuminated and simultaeneously accelerate gently. Bloke behind thinks I am still gently slowing and continues to gently slow himself. I on the other hand am speeding up ever so slightly. I move into a position that is equidistant between the car in front and the bloke behind then hold position.
How was that dangerous? I put to you that I cannot (through the use of my LF"B" - not really braking just illuminating the brake light) cannot possibly have put either myself or anyone else in danger. In fact - I have spaced us all out a bit more reducing the danger.
People kill themselves on motorways in a variety of ways. My little LFB trick does not/cannot contribute to it. Try it yourself and see!
Joe911 said:
If I step off the pavement into the path of your car - and you could stop safely, but choose not to and run into me (because I am a dangerous fool for stepping into the road) - do you have a clear conscience (regardless of whether the police see you as at fault)?
Totally different situation. All vehicle drivers have a legal responsibility NOT to run people over.
Here's some scenarios.
a) You step out. I brake to avoid hitting you. Bloke behind rams into me because he was following too close. I have a clear concience - bloke behind does not. Lots of damage.
b) You step out. I look in my mirror see bloke behind too close. Decide to not brake as he'd damage my car. You fly over the top of my car. I DO NOT have a clear concience.
c) You step out. I brake to avoid you. Previously I did my trick to ensure bloke behind is a little further back. He also stops in time. I have a clear concience, no damage to my car, so does bloke behind. I'm happy. Both drivers yell at you for being a twit - BUT NO HARM DONE!
>> Edited by Don on Friday 9th December 11:53
>> Edited by Don on Friday 9th December 11:54
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