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Old 17th December 2004, 17:42   #1
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Default How to change gears

guys,
we have always been seeing heavy vehicle drivers pushing the accelerator before downshifting.also i had read that blipping the throttle before u downshift gives a smoother shift without the normal jerk u get,as u match the engine speeds.
so off late i have been trying this and have surprisingly found this to be true.the gear change is very much smooth lust like the upshifts.[FONT=Arial Black]
what i wanna know is
1. whether there can be any damage to the engine in the long run if u do this.
2. if no,then wat is the correct procedure for doing this,as i press throttle 1-2 times keeping the clutch pressed,but the heavy vehicle drivers press only once whenever they downshift on a slope.[/b]
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Old 17th December 2004, 17:58   #2
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1. no damage to the engine if u do this!

2. u can press the throttle once or twice - depends! after some practice u will figure out exactly how much to blip to get the revs up to the correct level for each gear/speed.

after u master this, try changing without the clutch! same principle - as long as engine speed is right - gear will just slot in as if the clutch was depressed!

works for both downshifting and upshifting. of course it makes more sense only using for downshifting.

in the case of upshifting - u have to wait for the engine speed to come down, before the gear will slot in.
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Old 17th December 2004, 19:15   #3
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What you're talking about is called toe-heel braking. Technically, the throttle is supposed to be blipped with your heel while the toe is busy handling the brake pedal.

I don't think it's wise to do this under normal conditions, when i'm driving normally i always press the brakes, wait for the vehicle to slow down and then change gears.

Toe-heel is basically used under racing conditions to improve lap times and make for a smooth run.

But for your normal driving it's always good to have a little engine braking while you slow your car down. It not only helps the brakes last longer, but it's also a safer way of slowing down. Another reason why drivers are asked to drive in a lower gear when going downhill.

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Old 17th December 2004, 19:24   #4
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after u master this, try changing without the clutch! same principle - as long as engine speed is right - gear will just slot in as if the clutch was depressed!
Well, i dunno how useful that is, coz i've been closely watching the Best Motoring videos where cars are driven by GT champions who are the real deal. And, i've never ever seen any one off them try something like this, they always press the clutch and manage to get the best times out of every car.

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Old 17th December 2004, 22:57   #5
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Hey Shan2nu,

What speedsatya and bikerSG are talking about is simple "revvmatching" and not heel-toe downshifting.

Speedsatya, a single blip is better than a double blip(which doesnt serve any real purpose IMO).
Does this cause any damage to the engine you ask? well no, quite the opposite.... in increases the life of your clutch and causes less strain on the engine.

Check out this link to better understand this concept - cya
R

ps - Shan, also you are kinda right that the shifting without the clutch has no real purpose/advantage, but its just a way of perfecting your revvmatching, plus its fun to drive around without using the clutch.
Also, it comes in handy when your clutch stops functioning and you need to get home, as what happened to one of my friend's cars (provided you dont have to stop on the way! lol)
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Old 17th December 2004, 23:22   #6
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Shn2, I suggest you try downshifting while blipping...once you start getting it right and understanding its advantages even in everyday driving, you will never shift any other way again.

Come to think of it, you have said on many occassions that your vtec oversteers. Well, I think the problem may be that you are either downshifting in the corner or just before without blipping, hence throwing the car off balance, causing it to swing its tail out.

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Old 17th December 2004, 23:29   #7
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Quote:
increases the life of your clutch and causes less strain on the engine.
Less strain on the engine or drive shaft? Coz the engine will be revved in any case.

Quote:
What speedsatya and bikerSG are talking about is simple "revvmatching" and not heel-toe downshifting.
Ok, so you blip the throttle and downshift. It's ok for normal use, but if you do that on a race track, you're losing time coz you have to blip, shift and then brake. Toe-heeling lets you do all three in one shot.

Speedsatya, i suggest that you watch some of the Best Motoring vids coz they have these pedal cams which show how the feet are moving at all times. It's amazing how much control these guys need to have on the car, and they're so used to it that don't even have to think about it, it just comes.

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Old 18th December 2004, 00:18   #8
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Quote:
after u master this, try changing without the clutch! same principle - as long as engine speed is right - gear will just slot in as if the clutch was depressed!
i wudnt make it a habit.. its def. bad for ure car
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Old 18th December 2004, 00:45   #9
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Shn2, I suggest you try downshifting while blipping...once you start getting it right and understanding its advantages even in everyday driving, you will never shift any other way again.
Frankly, i'd rather make it a habit to toe-heel. It's always safer to have the brakes pressed while doin this.

What you guys are talking about is blipping the throttle when braking isn't involved, like when you have to down shift to overtake a slow vehicle in front. Blip the throttle, downshift, match the revvs and take off.

But if you're entering a corner at speeds your car isn't capable of handle that corner at, you have to press the brakes and the only way you can blip the throttle at that point is by toe-heeling.

Shan2nu

Last edited by Shan2nu : 18th December 2004 at 01:02.
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Old 18th December 2004, 10:09   #10
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Frankly, i'd rather make it a habit to toe-heel. It's always safer to have the brakes pressed while doin this.
The thing is, you dont always want to brake before a corner do you? Heal n toe is a diff. matter, closely related to this. If you don't get the revvs matching right, you aint gonna get a clean downshift. To start of with, try this first, then progress to heal n toeing.

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What you guys are talking about is blipping the throttle when braking isn't involved, like when you have to down shift to overtake a slow vehicle in front. Blip the throttle, downshift, match the revvs and take off.
Exactly! Or when you are coming upto a corner which has a decreasing apex, you shift down early but you dont need the brakes. Hell, I use engine braking a lot, not just when I'm driving fast. I think its because I ride bikes. Its a habit you get into (or should) as while you can usually get away with unbalancing a car mid corner, when you're on 2 wheels, that can get pretty scary.

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But if you're entering a corner at speeds your car isn't capable of handle that corner at, you have to press the brakes and the only way you can blip the throttle at that point is by toe-heeling.
yes, ofcourse. Lemme know how your Vtec's handling improves once you start using this!!

Rt

Last edited by Rtech : 18th December 2004 at 10:12.
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Old 18th December 2004, 11:35   #11
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If it's the normal revvmatching you guys are talking about, then i already am in the habit of doin it.

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Old 20th December 2004, 13:08   #12
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these are 2 totally different methods - used in totally different situations!

Heel and toe is used when braking is required! this method is used by all race drivers whenever they need to slow down for a corner (slow in - fast out).

the other method which sppedatys was talking about is more related to road riding/driving. it involves matching the car speed to the engine revs. upshifting without the clutch is more relevant on bikes, as clutch use requires more time. try it out for urselves!

for cars - downshifting without the clutch is used in racing. i think the term they use is 'dogging' - i dont remember the term exactly! it saves them time in gear changes! I am guessing that this is the principle they use in F1 cars, as they dont have clutches!
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Old 20th December 2004, 13:19   #13
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guys,
i do try this nowadays.but when i am at higher speeds,it works as the jerk which u normally get when downshifting is not there.the shift is soo smooth.but sometiems i get it real wrong .it happens as i blip the acc. ,but change the gear when the revvs have already cum down.so at this pt. u get the jerk.
sometimes in the excitement of doing this,u floor the acc jsut before declutching and so u actually race ahead .thsi can be pretty ttricky if ur downshifting to stop at a signal,as u might bang into someone.
but when u get it right ,the feeling is awesome.everytime i do it wrong ,i promise that i am not gonna do it again ,but then its something u cannot avoid once u no u can do it right.
the bus and truck drivers and almost all other CV drivers use this method while stopping or going down a slope.
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Old 20th December 2004, 13:25   #14
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Hey SG, its real simple shifting gears in F1 cars...just pull/push a paddle behind the wheel and the computers do everything else.

But yes, in the lower formula's that still use H pattern gearboxes (not many nowadays), most downshifts are done without the clutch. Infact the only time you really use the clutch is when you are starting from standstill or when coming to a stop.

And on a bike, well, clutchless upshifting comes naturally to almost all bikers I think. I started this from my first time ever on a bike! However, while downshifting, use of the clutch is still the best way to go i feel. I do downshift without the clutch at times, but thats only when I feel lazy Hell, they use the clutch for downshifting even in motoGP!

Rt

Last edited by Rtech : 20th December 2004 at 13:28.
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Old 20th December 2004, 15:06   #15
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Hell, they use the clutch for downshifting even in motoGP!
Very true, any pro driver will know that the clutch has to be used. I don't know where people got this idea of clutchless shifting from.If it was really that useful, we'd have seen every race driver use it, sadly i haven't seen any so far.

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