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Old 19th July 2005, 00:57   #1
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Question How to be more FE?

Always had this doubt.... and when I asked different people... they all had mixed answers... and I could never get what is right... so I'm posting it here and I hope I'll the right answer.

First question:-

If I'm using clutch more often like whenever I'm reaching 40kmph and I see something/someone coming on my way few metres ahead and I'm not sure whether that person or thing will move away by the time I reach him..... what should I do actually.... I mean I apply clutch full and break slowly by the time I reach him and change the gear according towhat's going to happen next or I just take my toe out of accelerator and slowly apply break and then use clutch according to the situation and change gear...... I'm asking this question not bcoz I don't know know what to do... but I want to know which is more fuel efficient.

Second Question:-

I'm going down hill in 4th..... shall I do nothing with my feet other than break..... or I press the clutch to the metal and try using break..... please tell me which one would have more fuel efficiency.

Third Question:-

Suppose 've to take a left/right turn few metres ahead.... assume 50 meters.... I put 1st gear first and take the initiative... and go for 2nd and gain some pickup.... and put the car in 3rd..... and by this time I'm at the turn... and I've to go back to my 2nd..... Hmm! whall I do this .................... or continue the car in 2nd with limited speed and after the turn I change to gear to 3rd and so on............ I could not understand wich one is more fuel efficient.


I always here mixed opinion about using the clutch.... can someone give me the exact technical info. on what should I be doing to make my car more fuel efficient.

Thanx in advance,
soNy

Last edited by sonycs : 19th July 2005 at 01:00. Reason: title been wrongly posted...
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Old 19th July 2005, 01:51   #2
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reply to your first question
i do not understand why you get scared when u see some car of object a few meters away but anyways its not good to use your clutch all the time

2nd : when your going down hill and its smooth let it be on fourth but keep your foot on the breaks no need to use the clutch unless you have to stop completely

3rd : if you are at the turn and u have just put in third...its better to change your gear to second for your car as i have always heard u should do that...do not know if all bhpians will agree with me or no...

and 1 more thing dude...i dont understand why you are so worried about your fe...which car do u drive..i drive a sail get 7 average still i dont think much about fe coz the car is really great...
anywayz 1 suggestion...if u really really want to save your fuel..then on a downhill shut your car...no fuel consumption at all..steerin gets a bit hard and even the breaks but dude U SAVE YOUR FUEL
hehehe just kidding
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Old 19th July 2005, 01:55   #3
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When braking from 4th, brake first and then declutch. Don't instantly hit the clutch.

When coming downhill, stay in a lower gear. And don't keep your foot on the brakes. They will overheat, and not respond when you need them the most.

Remember, FE is a good thing to worry about, but safety comes first.
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Old 19th July 2005, 02:47   #4
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1st ans.-
you should leave that clutch alone ...brake when needed and shift to neutral ..(u dont need to use a clutch while shifting to neutral ,jus takee your foot off the gas )..change bac to the desired gear once you pass that man..

2nd ans-
drive downhill with 4 or overdrive engaged...apply brakes when needed not all the timem...

3rd ans-
Quote:
I could not understand wich one is more fuel efficient.
now i really need to know what you drive and whats the FE you get from it..
whole idea is to keep the revs low ,at the right engine speed a car will give a better mileage...keep the revs limited to 2000 rpm ..
now you cant really go around worry about enter and exit speed/gear for each corner ....
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Old 19th July 2005, 10:51   #5
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Quote:
Originally Posted by sonycs
If I'm using clutch more often like whenever I'm reaching 40kmph and I see something/someone coming on my way few metres ahead and I'm not sure whether that person or thing will move away by the time I reach him..... what should I do actually.... I mean I apply clutch full and break slowly by the time I reach him and change the gear according towhat's going to happen next or I just take my toe out of accelerator and slowly apply break and then use clutch according to the situation and change gear...... I'm asking this question not bcoz I don't know know what to do... but I want to know which is more fuel efficient.
Sonycs,

Firstly, the correct way to do brake is to NOT press the clutch until the the car is about to start knocking ( <1000RPM ), or unless you need to downshift. This provides far greater control, and much shorter braking distances.
Regarding the FE, i have mentioned in some other threads as well, that if your car is at speed and you completely take your foot off the accelerator (and press the brake if neccessary) the car uses NO fuel at all. Whereas if you were to press the clutch, the car would use fuel just to keep the engine idling while you use the brakes to slow down.

Quote:
Originally Posted by sonycs
I'm going down hill in 4th..... shall I do nothing with my feet other than break..... or I press the clutch to the metal and try using break..... please tell me which one would have more fuel efficiency.
Once again, MPFI cars will not use fuel if you are rolling downhill at a decent speed in gear without the accelerator pressed.
Regarding saving your brakes, the steeper the slope, the lower the gear you would want to be in (and therefore more engine braking is provided so less use of brakes needed).

Quote:
Originally Posted by sonycs
Suppose 've to take a left/right turn few metres ahead.... assume 50 meters.... I put 1st gear first and take the initiative... and go for 2nd and gain some pickup.... and put the car in 3rd..... and by this time I'm at the turn... and I've to go back to my 2nd..... Hmm! whall I do this .................... or continue the car in 2nd with limited speed and after the turn I change to gear to 3rd and so on............ I could not understand wich one is more fuel efficient.
Since you are soooooo concerned abt FE, you may as well shift to 3rd....wont really make any sort of noticable difference to your FE, but maybe it will give you peace of mind.

Quote:
Originally Posted by sonycs
can someone give me the exact technical info. on what should I be doing to make my car more fuel efficient.
You might want to try increasing your tire pressure by 2-4psi if its still within reasonable limits. You should notice a difference.

As v1p3r said, dont ever even sacrifice 2% of safety for a possible 20% gain in FE.

cya
R

Last edited by Rehaan : 19th July 2005 at 10:52.
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Old 19th July 2005, 12:45   #6
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Quote:
Since you are soooooo concerned abt FE, you may as well shift to 3rd....wont really make any sort of noticable difference to your FE, but maybe it will give you peace of mind.
Yes, and flip side would be lesser control on turn (coz you are entering the turn at probably higher speed in higher gear, so if you realize that you have to reduce speed suddenly on turn, you need sharper braking).

Quote:
You might want to try increasing your tire pressure by 2-4psi if its still within reasonable limits. You should notice a difference.
FE will go up but the ride will be bumpier. So, your choice
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Old 19th July 2005, 14:47   #7
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As many people have mentioned already,

1) Just use the brakes until you get closer to knocking, and then downshift. Don't keep the clutch pressed, it should be used only for gear changes.

2) Instead of using the brakes to control your speed, shift to the right gear for that speed, don't use the brakes.

3) Unless you are started from a complete halt, you don't need to shift to 1st gear. Depending on the width and angle of the turn, pick either 2nd or 3rd gear and complete the whole turn with it and then up shift. Turning the steering and changing gear at the same time is not very safe or easy. If the steering slips from your lone hand, you may end up somewhere else...

BTW, these are recommended ways of driving, not sure about their FE merits. We in Team-BHP put safety first.

dadudeonfire, couple of your suggestion are down right dangerous, like going downhill on 4th with brakes applied (destroying brakepads) or switching off engine on the downhill.

Last edited by Samurai : 19th July 2005 at 14:49.
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Old 19th July 2005, 14:59   #8
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Quote:
Originally Posted by dadudeonfire
ri drive a sail get 7 average still i dont think much about fe coz the car is really great..
You get 7 on Opel Sail and you dont care about FE? Wow! Do you own a Petrol pump, or getting married to daughter of pump owner? Just kidding! Yours must be 1.6 Sail, isn't it?
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Old 19th July 2005, 15:07   #9
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Also, dont switch off your engine if you are going to stop for less than 2 minutes. You lose all benefits of switching off your engine if you start it within two minutes of stopping it.
And the best way of being fuel efficient (short of pushing the car yourself) is to drive as if there is an egg between ur foot and the accelerator. And dont use the AC.

Cheers
Amitoj
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Old 19th July 2005, 15:24   #10
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Quote:
Originally Posted by RX135
You get 7 on Opel Sail and you dont care about FE? Wow! Do you own a Petrol pump, or getting married to daughter of pump owner? Just kidding! Yours must be 1.6 Sail, isn't it?
no dude its 1.4...its not that i do not care about it but i do not think sooo much like when im taking a turn ..what i should do and all that...can u guys help in letting me know why i am getting such an average...i thought this was normal but now evre1zz like howz that possible n all...dude i fill full tank..i drive around when the fuels over..car is driven around 275-300 kms...and when i again amke it full it takes about 42-43 litres...the capacity is 45-46...
let me also know guys how to increase my fe...hehehe
i used 2 revv alot...but now i drive normally dont go beyond 3 rpm...getting my car modified now...getiting magz..will that affect my fe too?
if it does then i think ill have to go for LPG...modified sail wid lpg
hehehehe
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Old 19th July 2005, 16:11   #11
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Buddy mosy of these cars work on Vacuum assist brakes,
So swithding off the engine when cruisin downhill,
will tremendously drop you braking ability, not to mention the obvious lack of control & inability to use the throttle to respond to some situation

And cooking your brakes to a crisp!!!!!!!!
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Old 19th July 2005, 16:18   #12
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Quote:
Originally Posted by dadudeonfire
let me also know guys how to increase my fe...hehehe
Opel cars are not known to be Fuel efficient anyway They are supposed to provide fabulous ride though.

And you want to increase your FE? Keep on re-reading this thread every now and then
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Old 19th July 2005, 16:31   #13
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opels are not exceptional when it comes to mileage ..but 7kmpl is really bad,
its the driving style which is to be blamed here not the car...

a corsa will return a 10to11 kmpl if driven below its powerband...
..if your hitting 3000 rpm before each change your rewarded with a 7-8 kmpl...
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Old 19th July 2005, 16:36   #14
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Switching off the engine will make your brakes and steering uncontrollable. The brakes become ineffective and the steering will become harder than a truck steering, almost unmovable.
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Old 19th July 2005, 17:04   #15
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use your clutch only when you have to change gears o rwhen you are about to stall in first gear.so this answers your first question.


on a downhill stretch ,if there is not much traffic ahead of you you can continue in top gear.but its advisable to use engine braking on a downhill stretchi.e try going down in a lower gear so that u dont have to do the braking.constant braking on a downhill stretch will heat up your brakes and reduce their efficiency.
so dont go for FE on d ownhill stretch.


about the left-right turn,always shift to a lower gear when you approach a turn so that you have already slowed down before you need to apply your brakes.



and keep 1-2 psi more than recommended in your tires.and dont over revv your engine ,driving between 40-60 kph in the top gear shoul dgive you best FE figures.
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