Correct Usage of Clutch While Braking?

[mukeshus]

@ Mr.Boss: For the 4th question i don't know in what context you have said it.

Lets not continue OT.

Well my replies goes as per my experience of driving Scorpio for 33 months.

I feel that driving the vehicle without causing uneasiness to rear passengers is of atmost important as well as their safety.

As they are side facing.

Regarding the 5th question, what i meant was brake pedal doesn't touches the floor.
As is the case with accelerator & Clutch which can be pressed and depress fully.

Regarding the 2nd question, Why not?
I am replying as far as my experiences of driving.
I cannot enforce my driving skills to other, each may have their own way of driving.
Each may have different opinions, which they may feel they are correct.
I am not forcing anyone to follow my habbit.

 

[Mr.Boss]

@Mukesh,
Agree with you that the driving style varies from person to person and sometimes a different style for the same person from time to time.

I'm not speaking from my experience (though I'm driving for more than 9 years right from M800 to Civic) All those are from the studies and reviews from drivers all over the world (sorry I could not reveal the source here)

-Technically brake pedals can be floored (Floored is the term used to represent pressing the pedal to its most possible extent and not touching the floor)
-From studies of panic braking, the time between the driver recognising brakes to be applied and the vehicle stand still condition is less than 7.7 seconds (sorry again, I cant reveal the source, its confidential) In such a case, do you think downshifting is possible?

 

[mukeshus]

@Mukesh,
Agree with you that the driving style varies from person to person and sometimes a different style for the same person from time to time.

I'm not speaking from my experience (though I'm driving for more than 9 years right from M800 to Civic) All those are from the studies and reviews from drivers all over the world (sorry I could not reveal the source here)

-Technically brake pedals can be floored (Floored is the term used to represent pressing the pedal to its most possible extent and not touching the floor)
-From studies of panic braking, the time between the driver recognising brakes to be applied and the vehicle stand still condition is less than 7.7 seconds (sorry again, I cant reveal the source, its confidential) In such a case, do you think downshifting is possible?

And i do speak only from my experiences & not through facts.

May be you have experience of driving more than me and you may be right.

Well i have never come across such a situation to reply.
And that too i maintain a healthy distance, and my eyes are always concentrated on when the other person(Vehicle in the front) may brake and at what speed he would be at.
And i never follow the vehicle in the front, to his tail.
You need not reveal the source if it refrains you from sharing with others.

 

[mastersquall]

wwhhoo you guys able to think so much at time of panic braking . i can think of only one think PRESS BRAKE AS HARD AS POSSIBLE

 

[freakdude]

wwhhoo you guys able to think so much at time of panic braking . i can think of only one think PRESS BRAKE AS HARD AS POSSIBLE

Never ever ever ever do that in case of panic braking unless your car is equipped with ABS. Slamming the brakes hard jams the wheels and makes them skid letting the car go out of control. Apply brakes hard but if wheels skid release brakes by say 5% and apply again and try downshifting at the same time if situation permits.

freakdude.

 

[Figoian]

Very good thread but to be frank i never use engine braking while stopping the car. Say for example if i am approaching a toll booth or a signal which i see before hand , i just put the car to neutral and apply the brakes softly to bring the car to a smooth halt. I know this is not the correct procedure but i got used to this!

Heheeheee. Guess, you are doing this for FE. However, as the Engine Braking isn't utilized, the usage of brake pads are more and hence can result in early wear of Brakes. Whatever you save on Fuel may run out here.

How can you gradually brake in emergency situations, when you press the brakes hard, downshifting helps a lot and vehicle will be in complete control.

Agree that downshifting helps in braking better, but how about the FE? I know, FE isn't as important as saftey... But still, with the ever raising fuel prices, isn't FE a concern for everyone around here???

 

[drivetech4]

Never ever ever ever do that in case of panic braking unless your car is equipped with ABS. Slamming the brakes hard jams the wheels and makes them skid letting the car go out of control. Apply brakes hard but if wheels skid release brakes by say 5% and apply again and try downshifting at the same time if situation permits.

freakdude.

Very rightly said Freakdude!

+1 Thank god I have got ABS on My Car. It gives me confidence to drive on wet and slippery highway.

 

[drivetech4]

Heheeheee.... Guess, you are doing this for FE. However, as the Engine Braking isn't utilized, the usage of brake pads are more and hence can result in early wear of Brakes. Whatever you save on Fuel may run out here...



Agree that downshifting helps in braking better, but how about the FE? I know, FE isn't as important as saftey... But still, with the ever raising fuel prices, isn't FE a concern for everyone around here???

Downshifting in any case of braking is a natural phenomenon. Either you move it in neutral or the lowest gear, its all nothing but downshifting, as you will start moving the car with either 1st or 2nd gear after the braking.One just can not brake without downshifting, else the engine stalls, and for downshifting you always need to press clutch.
No offences meant figoian, but I don't think FE has do anything with this, If you have to consider FE all the time while you drive, then there wont be brakes on cars!

 

[Figoian]

Drivetech4: My comments are inline (bold).

Downshifting in any case of braking is a natural phenomenon. Either you move it in neutral or the lowest gear, its all nothing but downshifting, as you will start moving the car with either 1st or 2nd gear after the braking.One just can not brake without downshifting, else the engine stalls, and for downshifting you always need to press clutch. - Agreed. Thats the way generally anyone would do. But I have heard a lot from people that doesn't use clutch or downshift or change to neutral for FE. I guess, such procedures aren't right.

No offences meant figoian, but I don't think FE has do anything with this, If you have to consider FE all the time while you drive, then there wont be brakes on cars! - Agreed. But I have read somewhere, the appropriate way of Brake / Halt, one should downshift the same as Upshift... Means, 5-4-3-2-1. I am sure, that has an impact with FE. I thought the same was recomended here as well... Thus asked for that clarification. I am clear with your point now.

 

[autosafari]

Heheeheee. Guess, you are doing this for FE. However, as the Engine Braking isn't utilized, the usage of brake pads are more and hence can result in early wear of Brakes. Whatever you save on Fuel may run out here.



Agree that downshifting helps in braking better, but how about the FE? I know, FE isn't as important as saftey... But still, with the ever raising fuel prices, isn't FE a concern for everyone around here???

Hi Figoian

In another thread in TAI (A thread which discuss about 46 km/litre mileage obtained in TATA MANZA by Mr. Narayana Menon of Coimbatore.

In that Mr. Menon, who is in Limca Book of records for this, clearly say that the common practice by some people to shift gear to neutral actually decreases FE. Because according to him fuel consumption during idling is much more than fuel consumed during actual running at right rpm

 

[drivetech4]

Hi Figoian

In another thread in TAI (A thread which discuss about 46 km/litre mileage obtained in TATA MANZA by Mr. Narayana Menon of Coimbatore.

In that Mr. Menon, who is in Limca Book of records for this, clearly say that the common practice by some people to shift gear to neutral actually decreases FE. Because according to him fuel consumption during idling is much more than fuel consumed during actual running at right rpm

There is theoretical reason for that. This is not straight & true as mentioned above. When you calculate engine efficiency then the above statement applies. At Idling you are not withdrawing any power from the engine and the output efficiency of engine is very less as compared to the Input.All these things are measured in terms of heat efficiency or Thermal efficiency.
And since the engine efficiency at idling is low in a way it impacts the overall FE. That's why one should avoid Idling!

I feel like, I had gone back to year 2000 when I was studying Mechanical engineering. just FYI Prior to that I had also completed Diploma In Automobile Engineering.

 

[autosafari]

There is theoretical reason for that. This is not straight & true as mentioned above. When you calculate engine efficiency then the above statement applies. At Idling you are not withdrawing any power from the engine and the output efficiency of engine is very less as compared to the Input.All these things are measured in terms of heat efficiency or Thermal efficiency.
And since the engine efficiency at idling is low in a way it impacts the overall FE. That's why one should avoid Idling!

I feel like, I had gone back to year 2000 when I was studying Mechanical engineering. just FYI Prior to that I had also completed Diploma In Automobile Engineering.

drivetech4, could you please tell in simple terms whether actually FE decreases if you idle in between or whether FE increases if you idle (running in neutral)

To avoid confusion, please consider only FE here and do not mention about the loss of control and stability while running in neutral down a slope

 

[mukeshus]

Agree that downshifting helps in braking better, but how about the FE? I know, FE isn't as important as saftey... But still, with the ever raising fuel prices, isn't FE a concern for everyone around here???

Hey Figoian, you are thinking of FE during emergency situation?

 

[Figoian]

Hey Figoian, you are thinking of FE during emergency situation?

100% NOT... Infact, I guess will find no one here... May be, my point must have been confused/misapprehended by few... To make it clear, I am not concerned about FE at all... I have also explained my point in my previous post.

Secondly, I guess, this thread is not about Panic Braking or Emergency Situation...

 

[drivetech4]

drivetech4, could you please tell in simple terms whether actually FE decreases if you idle in between or whether FE increases if you idle (running in neutral)

To avoid confusion, please consider only FE here and do not mention about the loss of control and stability while running in neutral down a slope

Well happy to answer your query- The more time you keep you car at Idle, the FE will drastically go down.
Running in neutral is not called idling,and this should be avoided too.(will come back to it)
Idling means your car is stationery and engine is running.
The details-
HERE'S THE RULE OF THUMB: If you're in a drive-through restaurant, long ques at fuel station, Traffic signal with timer,or waiting for someone and you'll be idling and sitting for 10 seconds or longer... turn off your car's engine. Why??
For every two minutes a car is idling, it uses about the same amount of fuel it takes to go about 1.5 km. Research indicates that the average person idles their car five to 10 minutes a day.


Now I am sure Immediate question from many guys will come,



Does starting the engine require more fuel?


For starting the engine more amount of fuel is required, but it is equivalent to the fuel burnt for 10 secs of Idling. If you see a traffic signal showing 90 secs timer, it is advisable to shut the engine off. you will save fuel for 80 secs.


If you are going to be parked for more than 30 seconds, turn off the engine. Ten seconds of idling can use more fuel than turning off the engine and restarting it. And when you start your engine, don't step down on the accelerator, just simply turn the key to start.



Though Idling is recommended for Cold start, you should idle your car at least for 40 secs to a Minute. This is required for engine warm up and Turbocharger lubrication.(specially for diesel car)


Excessive idling can actually damage your engine components, including cylinders, spark plugs, and exhaust systems. Fuel is only partially combusted when idling because an engine does not operate at its peak temperature. This leads to the build up of fuel residues on cylinder walls that can damage engine components and increase fuel consumption.

Frequent restarting has little impact on engine components like the battery and the starter motor. Component wear caused by restarting the engine is estimated to not more than Rs 500 per year to the cost of driving, money that will likely be recovered several times over in fuel savings from reduced idling.
The bottom line is that more than ten seconds of idling uses more fuel than restarting the engine.

These are not my personal views, this has got scientific study base too.

Now regarding riding in neutral ,sometimes you see a toll post ay around 100 meters away, you are in speed of say 80 kmph, and you shifted to neutral. The car still runs with same speed because of monetum, ithe speed will reduce only if there is gradient, else speed will not go down below 60 kmph till you reach toll post, suddenly you see the speed breaker and press the break hard, consider Tyre wear, break pad wear, without saving in fuel.

Also when you pass over the speed breaker in neutral,It feel more bouncy, since you dont have any control over the car. This may affect the suspension too.( Guys please correct me if I am wrong)

So it is recommended that you gradual reduce the speed, downshift as speed reduces and come to halt, avoid riding in neutral.