Heel & Toeing
#61
LFB - brake with left foot, then apply accelerator with right once weight is transferred to front of car. Rear wheels have less grip due to weight transfer, therefore they spin up. You turn into the corner, back comes round , you release brake and floor accelerator whilst applying opposite lock. Emerge from corner with smokin' back wheels to rounds of applause from crowd which has gathered. Either that or you end up backwards in a ditch
Disclaimer: I can't H&T or LFB, this is just the theory!
Disclaimer: I can't H&T or LFB, this is just the theory!
#62
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Originally Posted by Toerag
LFB - brake with left foot, then apply accelerator with right once weight is transferred to front of car. Rear wheels have less grip due to weight transfer, therefore they spin up. You turn into the corner, back comes round , you release brake and floor accelerator whilst applying opposite lock. Emerge from corner with smokin' back wheels to rounds of applause from crowd which has gathered. Either that or you end up backwards in a ditch
Disclaimer: I can't H&T or LFB, this is just the theory!
Disclaimer: I can't H&T or LFB, this is just the theory!
#64
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It was those BMI vids that got me started at heel and toe-ing; still trying to get it right - at the moment, not doing it results in faster 'lap times' (er...) but practice makes perfect.
#65
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Oh it is amusing the comments you youngsters make about H&T. Unfortunately I'm (almost) old enough to remember HAVING to use the technique.
Double de-clutching is a necessity in older cars without synchromesh. With a modern gearbox, if you de-clutch and move the gear lever, the gearbox synchronises the speed of the gears before allowing them to mesh. An old car doesn't do that so the driver has to do it. When you de-clutch, the set of gears connected to the engine become free running. Changing up is easy as the gears tend to slow down to the new speed naturally. Changing down means that the gears have to be speeded up. The only way to do this is by using the engine. Supose we are down changing from 3000 rpm in one gear to 4000 rpm in another. If the clutch is pressed and the gear lever pushed, the new gears are 1000 rpm out of synchromesh (let's assume a constant road speed for now).
So here's what we do. De-clutch, move gear lever to neutral, let up clutch, blip throttle to new speed (4000 rpm), de-clutch, engage lower gear, let up clutch to engage drive. Notice the two presses of the clutch, hence "Double de-clutch". The new gear speed is judged by ear and the whole operation is as fast as a normal downchange.
Now onto H&T. VERY old cars didn't have their pedals in the same place as now. Some didn't have them in a straight line but were place with the brake ahead of the throttle. This probably had something to do with where the brake was on a horse drawn cart. With this arrangement, you could use the toe on the brake and the heel on the throttle.
Now imagine trying to double de-clutch while braking. Three pedals and only two feet means that one foot has to work two pedals. Since the brake and throttle were best placed and their movements were less, they were the obvious ones. When pedal positioning standardised at the current design, the right foot had to be used sideways. The reasos for H&T is to double de-clutch while braking so do the same as above but rev the engine with the right side of the right foot while braking with the left side.
Get all of this right and your gear changes become smoother and the synchromesh has less work to do. In theory, if the gear speeds are perfectly sychronised, you don't need the clutch at all. So if a clutch fails, you can drive home once the car is moving.
Modern drivers, including that video, dont H&T properly, they only rev the engine during a gear change so that the clutch can be re-engaged quickly and smoothly. With modern gearboxes, that's probably all that's required. Dinosours like me still do it the old way. It does have the advantage (for me) that I can still drive old cars without gear changing problems. I admit it's not necessary on modern cars but I do it out of habit and have done so for so long that my gear changes are as fast as others who don't H&T. It also makes block changes easier. I can brake long and hard ito a tight bend then drop from 4th into 2nd. Why use 3rd at all? Engine braking is minimal compared to the car brakes on modern cars. Using all the gears used to be necessary on older cars as their brakes were poor so needed all the help they could get and with only 3 gears (sometimes 2) block changing was less important. There was also the problem that, without synchromesh, block changing was more difficult.
Don't be fooled by Petter Solberg's gear changing. A competition sequential dog box is a whole different animal. Look at this site.
http://www.hewland-engineering.co.uk/svga/help.htm
Is double de-clutching needed on modern cars? Opinions differ on that. I use it because I always have and I drive old cars occasionally so like to keep in practice. I can't see any disadvantage, if it's done properly but the need is probably long gone.
There you have the history lesson. Hope it's interesting. I might ramble on about left foot braking soon.
John
Double de-clutching is a necessity in older cars without synchromesh. With a modern gearbox, if you de-clutch and move the gear lever, the gearbox synchronises the speed of the gears before allowing them to mesh. An old car doesn't do that so the driver has to do it. When you de-clutch, the set of gears connected to the engine become free running. Changing up is easy as the gears tend to slow down to the new speed naturally. Changing down means that the gears have to be speeded up. The only way to do this is by using the engine. Supose we are down changing from 3000 rpm in one gear to 4000 rpm in another. If the clutch is pressed and the gear lever pushed, the new gears are 1000 rpm out of synchromesh (let's assume a constant road speed for now).
So here's what we do. De-clutch, move gear lever to neutral, let up clutch, blip throttle to new speed (4000 rpm), de-clutch, engage lower gear, let up clutch to engage drive. Notice the two presses of the clutch, hence "Double de-clutch". The new gear speed is judged by ear and the whole operation is as fast as a normal downchange.
Now onto H&T. VERY old cars didn't have their pedals in the same place as now. Some didn't have them in a straight line but were place with the brake ahead of the throttle. This probably had something to do with where the brake was on a horse drawn cart. With this arrangement, you could use the toe on the brake and the heel on the throttle.
Now imagine trying to double de-clutch while braking. Three pedals and only two feet means that one foot has to work two pedals. Since the brake and throttle were best placed and their movements were less, they were the obvious ones. When pedal positioning standardised at the current design, the right foot had to be used sideways. The reasos for H&T is to double de-clutch while braking so do the same as above but rev the engine with the right side of the right foot while braking with the left side.
Get all of this right and your gear changes become smoother and the synchromesh has less work to do. In theory, if the gear speeds are perfectly sychronised, you don't need the clutch at all. So if a clutch fails, you can drive home once the car is moving.
Modern drivers, including that video, dont H&T properly, they only rev the engine during a gear change so that the clutch can be re-engaged quickly and smoothly. With modern gearboxes, that's probably all that's required. Dinosours like me still do it the old way. It does have the advantage (for me) that I can still drive old cars without gear changing problems. I admit it's not necessary on modern cars but I do it out of habit and have done so for so long that my gear changes are as fast as others who don't H&T. It also makes block changes easier. I can brake long and hard ito a tight bend then drop from 4th into 2nd. Why use 3rd at all? Engine braking is minimal compared to the car brakes on modern cars. Using all the gears used to be necessary on older cars as their brakes were poor so needed all the help they could get and with only 3 gears (sometimes 2) block changing was less important. There was also the problem that, without synchromesh, block changing was more difficult.
Don't be fooled by Petter Solberg's gear changing. A competition sequential dog box is a whole different animal. Look at this site.
http://www.hewland-engineering.co.uk/svga/help.htm
Is double de-clutching needed on modern cars? Opinions differ on that. I use it because I always have and I drive old cars occasionally so like to keep in practice. I can't see any disadvantage, if it's done properly but the need is probably long gone.
There you have the history lesson. Hope it's interesting. I might ramble on about left foot braking soon.
John
#66
Fair enough, but heal and toeing without double de-clutching has it's advantages. Ie if you drop from 4th to 2nd on a mk2 escort using the syncro and not reving it what happens? scary stuff!
Personally i double declutch when driving normally, because i like the feeling when it slips into gear without using the sychro, and vary between that and h&ting when pushing on.
Regardless of the history it makes driving smoother although is doubtlessly not required.
Dave
Personally i double declutch when driving normally, because i like the feeling when it slips into gear without using the sychro, and vary between that and h&ting when pushing on.
Regardless of the history it makes driving smoother although is doubtlessly not required.
Dave
#70
the greatest way to leran left foot braking is to drive an auto for a while.
i learnt in a vauxhall omega - christ i can make that thing shift now!
i have now totally mastered LFBing and its great for holding the car on boost when overtaking.
heel and toeing i have yet to master, i too find modulating the brakes the trick bit.
i learnt in a vauxhall omega - christ i can make that thing shift now!
i have now totally mastered LFBing and its great for holding the car on boost when overtaking.
heel and toeing i have yet to master, i too find modulating the brakes the trick bit.
#71
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lfbing really is the nuts, when people expect to overtake you as accelerate out of a bend thinking there will be a couple of seconds before it goes, instanteous boost, and go, makes for seriously quick getaways,
interesing enough does anyone on here drive on gran turismo 4 (left foot braking) i.e pressing the brake and accelerator down???
interesing enough does anyone on here drive on gran turismo 4 (left foot braking) i.e pressing the brake and accelerator down???
#72
ummm LFB is exactly that - useing your left foot to brake. i only advise it being used to give balance to a car normally round corners - other posts talk of spooling up the turbo to get bigger boost - yes that does work by useing your left foot on the brake, but this isnt left foot braking.....does that make sense?
hope i dont annoy anyone...
also why are people even talking about double de clutching....its completely uneeded, but practicing it will improve your co-ordination and control on the pedals!!! so cant be a bad thing. maybe there may be an occasion where you loose your syncro in a race....
heal toeing also isnt actually heel toe. in practice you use the side of your foot. im not sure how many of you guys have driven a race prepped car, but the pedals are all at very similar heights (depends on drivers as well of course) and close together to make this process easy. its actually harder, in my experience, to do it in a road car then the real thing!
sorry if this has all been said i didnt read every post...
hope this is of some help....not trying to get at anyone!!
hope i dont annoy anyone...
also why are people even talking about double de clutching....its completely uneeded, but practicing it will improve your co-ordination and control on the pedals!!! so cant be a bad thing. maybe there may be an occasion where you loose your syncro in a race....
heal toeing also isnt actually heel toe. in practice you use the side of your foot. im not sure how many of you guys have driven a race prepped car, but the pedals are all at very similar heights (depends on drivers as well of course) and close together to make this process easy. its actually harder, in my experience, to do it in a road car then the real thing!
sorry if this has all been said i didnt read every post...
hope this is of some help....not trying to get at anyone!!
#73
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i heel and toe constantly now, even going to the shops
once you learn it, you start to hate not useing it for some reason, it sounds "harsh" on the car when i dont use it
once you learn it, you start to hate not useing it for some reason, it sounds "harsh" on the car when i dont use it
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