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Old 30th January 2007, 21:32   #76
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shan2nu thats one hell of a video. that too on the nurbrugring. man the revmatching. keep seeing it over and over again.

just showed it to a couple of guys at office and they are amazed how someone can press both accelerator and brake at the same time and how it is useful since you are negating the effect of braking.

i ended up laughing at the guy and he walked off. lol..
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Old 30th January 2007, 21:53   #77
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Beautiful video. I notice that the guy presses the clutch a little before lifting his foot off the accelerator and shifting gear. Seems like he is riding the clutch -- maybe to save time while shifting? Possibly the clutch action is not immediate upon pressing and so he saves time by pressing a little in advance before shifiting?
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Old 30th January 2007, 22:51   #78
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Motoharu Kurosawa and Keiichi Tsuchiya are amazing with their foot work.

You guys should see the Tsukuba time attack by Tsuchiya in the Arta NSX (JGTC) car. It'l blow you away.

I'l post some more vids related to shifting as i come across them.

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Old 31st January 2007, 03:10   #79
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Originally Posted by rks View Post
And if you ever get into an oversteer situation on a FWD, you will need acceleration to provide the traction to get you out of the skid. If you are coasting in neutral on a FWD, approach a corner too fast, brake and find that your car oversteers, you will be left with insufficient traction to get you out of the skid.
You'd have to have pretty bad brake balance in a FWD to have that problem, but I'd agree that throttle solves so many problems with FWD. FWD is skid-correctable from what would otherwise be impossible angles with full opposite lock and throttle.

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I think it is safe to assert that you should *never* coast in neutral when you are overtaking on a two-way road, for you may find yourself in any of the following situations:
I think that goes without saying. Why would you coast when overtaking?

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In India you are almost always driving on narrow two-way roads with a wide variability in the speeds of the vehicles (ranging from painfully slow trucks/two-wheelers to high-speed sedans), so you will need both braking and acceleration at unpredictable times to drive safely. This is in addition to what others have already pointed out.
Perhaps that's the one thing I've overlooked. Here in the US there are a few real opportunities for it (the long hill on the 4-lane highway I described earlier), but perhaps there aren't similar roadways where you are. All in all, done at the appropriate times, it hurts no-one -- if you felt like screwing around, you could even do it engine-off (but DO NOT try that in an automatic in neutral, it will eat the trans alive).


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Originally Posted by vid6639 View Post
just showed it to a couple of guys at office and they are amazed how someone can press both accelerator and brake at the same time and how it is useful since you are negating the effect of braking.

i ended up laughing at the guy and he walked off. lol..
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Old 31st January 2007, 09:51   #80
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Basically what you're saying is that TECHNICALLY, shifting to neutral and coasting is OK. I agree, nothing wrong with that. However, in the real world, is it advisable? No.

Now I'm not talking shifting to neutral from about 15kmph while coasting upto a traffic light. We've all done that at some point. I just don't want someone here to dump the car in neutral while doing a 100kmph!!
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Old 31st January 2007, 09:58   #81
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And honestly, how often do you see a kid running across the street and feel the need to mash the throttle?
Hi,

You would be amazed at how often one would feel the need to sverve or mash the throttle to avoid hitting kids, animals etc. Almost 99% of the people here do not observe lane discipline.

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Old 31st January 2007, 11:17   #82
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Now I'm not talking shifting to neutral from about 15kmph while coasting upto a traffic light. We've all done that at some point. I just don't want someone here to dump the car in neutral while doing a 100kmph!!
Still, how is that a terrible, dangerous thing? If anything, maneuvering while building speed is a dicier proposition than braking or maneuvering while coasting. Most people most of the time would be better served by coming to a cautious stop in a questionable traffic situation, or dodging if it is impossible to stop in time.

Absolutely hands down the best "save" I've ever had was in an automatic car with no power available (and none used) at the time of the maneuver. I was traveling down the street in a snowstorm at about 30-35mph when somebody who didn't look carfully turned out of a road directly in front of me. The car I was driving had tires that were completely ineffective in the snow (this is obviously a borrowed car -- I would never own such a vehicle), so when I stepped on the brakes there was very little deceleration. It BARELY started slowing down while firing the ABS pump. I lifted off the brake and dodged smoothly right, off the road and into a snowbank, blasted through the snowbank for maybe 40-50 feet, passing the car in the process, and turned back onto the road to avoid a telephone pole. The whole event happened over approximately 3-4 seconds.

Applying power over that interval - a true emergency maneuver - would have almost no effect on the velocity/path of the car.

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Originally Posted by viper View Post
You would be amazed at how often one would feel the need to sverve or mash the throttle to avoid hitting kids, animals etc. Almost 99% of the people here do not observe lane discipline.
Swerve, yes. Brake, yes. Accelerate? If it's truly an emergency, throttle isn't going to do much for you. Braking and cornering are limited only by the four tires' available traction. Acceleration has half the traction to play with (typically two wheels), but is further limited by the power the engine can develop -- most notably it will develop very little at first because you aren't driving around at peak torque all the time.

Last edited by Multiades : 31st January 2007 at 11:21.
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Old 31st January 2007, 11:52   #83
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Originally Posted by Multiades View Post
You'd have to have pretty bad brake balance in a FWD to have that problem, but I'd agree that throttle solves so many problems with FWD. FWD is skid-correctable from what would otherwise be impossible angles with full opposite lock and throttle.
Another scenario when you can get oversteer in a FWD is when your rear tyres are worn out and your front tyres are brand new. This happens frequently because people don't rotate tyres, find that the front tyres get worn out faster and replace them. Then they set themselves up for some serious oversteer. My car manual explicitly warns against this scenario and advises that new tyres be put in the rear, but the garage mechanics seldom heed this advice, and people seldom take care of their tyres by proper rotation.

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I think that goes without saying. Why would you coast when overtaking?
Of course you knew that high-speed coasting is not advisable when there is a lot of slow-speed traffic and you have to cut lanes/overtake (whether in one-way or two-way roads), but this is almost inevitable in Indian driving conditions and I wanted to stress that point to newbies who may be reading this forum.
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Old 31st January 2007, 12:26   #84
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I usually ride a bike, and coasting in neutral is a surefire way to end up with some road rash sooner or later. I simply carry that into 4-wheelers.

I can't even remember the number of times I've had to get on the gas suddenly to avoid a cab keeps coming at you at an intersection. If I were coasting in neutral, I'd just be wasting precious seconds getting into a gear and accelerating to avoid becoming a hood ornament.
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Old 31st January 2007, 12:36   #85
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Originally Posted by Rtech View Post
I can't even remember the number of times I've had to get on the gas suddenly to avoid a cab keeps coming at you at an intersection. If I were coasting in neutral, I'd just be wasting precious seconds getting into a gear and accelerating to avoid becoming a hood ornament.
What Multiades may not realize is that in our intersections, quite often the law of the jungle holds. Accelerating when approaching an intersection often sends out a clear message to those who intend to cross your path that they had better change their minds quickly. Of course I wouldn't advise this tactic against the taxi cabs/bus drivers of Bombay.
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Old 31st January 2007, 13:18   #86
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Originally Posted by Rtech View Post
I usually ride a bike, and coasting in neutral is a surefire way to end up with some road rash sooner or later. I simply carry that into 4-wheelers.

I can't even remember the number of times I've had to get on the gas suddenly to avoid a cab keeps coming at you at an intersection. If I were coasting in neutral, I'd just be wasting precious seconds getting into a gear and accelerating to avoid becoming a hood ornament.
I will certainly defer to your experience with motorcylces, but as I understand it throttle is essential for adjusting the attitude of the bike in normal riding. Driving is not quite so precarious (static stability). Also, motorcycles use sequentials, so it's not quite the same as using an H-pattern where neutral is a flick away and you aren't compelled to go through other gears.

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Originally Posted by rks View Post
What Multiades may not realize is that in our intersections, quite often the law of the jungle holds. Accelerating when approaching an intersection often sends out a clear message to those who intend to cross your path that they had better change their minds quickly. Of course I wouldn't advise this tactic against the taxi cabs/bus drivers of Bombay.
That's probably the worst of all situations for coasting, in the same way that it would be unwise to approach a traffic light (when you aren't coming to a stop) in neutral.

Obviously coasting in neutral is for circumstances where you anticipate having to stop but don't need to do it immediately, or the somewhat rarer situation of just wanting to maintain speed downhill and give the engine a rest (my earlier downhill highway example). Let's look at the original thread starter's question again:

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Originally Posted by netarchie View Post
While driving at a certian speed say above 60 - 70 Kms/ hour, when i need to slow down my car , if suppose i am approaching a red light/Speed breaker, i usually shift my gears to the neutral , directly from the 5th or 4th geat and break genlty before i come to a comple halt or the speed at which i need to take off once again? This way i dont have to use the clutch much, just once to shift to the neutral.
in short, i shift to the neutral from a higher seed/higher gear and let the car come to a speed at which i can engage 2nd or 3rd gear.
just to give an e.g. if iam driving in the expressway at say 100 km/hr and when i see the sign - Toll 1000 meters ahead - i simply shift to the neutral and break gently till I approach the Toll booth , rather than shifting to 4th,3rd ect.
I do this while driving downhill also.(shifting to the neutral) but i do not keep my foot over the brakes.

by doing this i feel i am saving fuel.
Please correct me if i am wrong in the follwoing the above said method.
I will reiterate that in my opinion when approaching an intersection or a toll booth where a complete stop from speed is expected, it is perfectly acceptable, safe, and good practice to coast in neutral and apply the brakes immediately or eventually to come to a stop. Now that I'm reviewing the original question again I can say that I do it often and see no issue in the safety of that approach.

-Chris
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Old 31st January 2007, 19:29   #87
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Chris
I was the OP and have managed to give up the habit (coasting in neutral) as of now.
Though your explanations/arguments about this habit/method is quite convincing, I believe and as others have pointed out, In India it is better to be prepared for eventualities ( which are quite common) and staying in gear helps. I have experienced it myself.
Though you have pointed out that the above method is absolutely safe, but in our conditions it may in fact it is not so.
So, can we conclude by saying that the technique in itself is not wrong but its application hugely depends on the driving conditions of the place you drive??
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Old 3rd February 2007, 15:59   #88
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Originally Posted by netarchie View Post
Chris
I was the OP and have managed to give up the habit (coasting in neutral) as of now.
Though your explanations/arguments about this habit/method is quite convincing, I believe and as others have pointed out, In India it is better to be prepared for eventualities ( which are quite common) and staying in gear helps. I have experienced it myself.
Though you have pointed out that the above method is absolutely safe, but in our conditions it may in fact it is not so.
So, can we conclude by saying that the technique in itself is not wrong but its application hugely depends on the driving conditions of the place you drive??
While that sounds fair at first, I'm unwilling to completely concede the point. Yes, of course it depends on where you drive as far as specific circumstances are concerned. The time it is primarily reasonable to coast is when you are anticipating a complete stop and are in reasonably low-traffic circumstances. I can't possibly foresee this being bad practice no matter which country you're in. Hell, even coming to a complete stop in the presence of other cars (so long as nobody's trying to play Mad Max with you), it's pretty hard to see this as harmful. Again, I will advocate proper downshifting all day long -- I practice it myself and find it useful -- but on the point that it is somehow dangerous to coast in neutral, I must disagree on technicality.


Can somebody please describe to me the exact circumstance (in which you have planned to stop) where throttle application is commonly helpful and necessary in emergency circumstances to the average motorist? I'm just not seeing it. Why is turning or coming to a complete stop not a better (or technically safer) option?

While I understand throttle use in car control is essential, I don't believe for a second you guys all go screeching around at the limit of traction and are only saved by careful throttle modulation.



At this point I'm probably pushing trolling in this thread because I've reiterated my [apparently-unpopular] opinion so many times, so I'll try and cut back and find other threads to post in.
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Old 3rd February 2007, 20:32   #89
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Can somebody please describe to me the exact circumstance (in which you have planned to stop) where throttle application is commonly helpful and necessary in emergency circumstances to the average motorist? I'm just not seeing it. Why is turning or coming to a complete stop not a better (or technically safer) option?
Trust me, you can never be sure if you're really gonna halt. The guy behind you could lose control of his car or could be driving under the influence of alcohol and thus, maynot be able to stop in time.

In such a case, you'd be better of being in gear. By the time you realise, press the clutch, put the car in gear and accellerate, you'd have been rear ended.

A couple of months ago, an Indica got rear ended by a truck killing 2 of it's passengers.

In another case, an OHC 1.5 slowed down for a speed breaker and an oncomming (heavily overloaded) truck went off balance right next to the car and fell on it. Both passengers in the car were killed on the spot.

I once almost got rear ended by an Accent as i was slowing down for a speed breaker. The Accent guy prob didn't know about the breaker and kept accelerating. Had i not sped away, he'd have hit me real hard.

And then there was the case of Rehaan's Accent aproaching GTO's Vtec with locked wheels. I remember GTO doin a quick launch on the speed bump. LOL

Shan2nu

Last edited by Shan2nu : 3rd February 2007 at 20:34.
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Old 3rd February 2007, 20:40   #90
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Thats the best example Shan2nu. Happened to me once too. saw amber light approaching a signal at which no one was there. braked hard. cause it would have been red if i tried to shoot past and what happens instead, A girl driving a Santro rear ends my car and end up having Rs.50K of repairs.

If I had looked back and was in gear I would have jumped the signal. I generally glance at the mirrors before braking hard but missed it that time. I'm always in gear for that very reason If I see that the guy behind cant brake I accelerate.

My friends Esteem got converted to a 800 after he braked for a speed breaker but the truck behind didn't see it. The car was a total write off as the trucker was doing probably 60+kmph.

Highly unpredictable here and you never know when you have to brake dodge or even accelerate. You need to be ready to do any of the 3.
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