[pratheesh]

hello everyone,

I am new born driver (though i turned 22 last 10th, i got the license just last month), n from my one month experience I developed two driving styles. Please anlayse and post comments on it. Tell me whether I am correct or not.

Style 1 - Objective is to decrease fuel consumption
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I commonly drive in this style, because i am from a lower middle class family, and petrol costs me a lot.
Well, in this mode I shift up the gears rapidly (though without jerking),when the engine reaches the minimum (I mean the engine runs smoothly without knocking) rpm of that gear.
As a result i am able to reach the Top gear easily and able to ride at the lowest speed as possible.
Whenever engine rpm reduces (brakes!!!), i refrain from shifting down the gear, and shifts down only if I feel that the engine is going to knock.

Style 2 - Objective is to decrease the time of travel
-----------------------------------------------------

Often used when I am toooo late. During this mode, i raises the engine at a gear till it start to moan, so that i could accelerate (I presume that you accelerate better at lower gears than at top gears) to a maximum limit. By doing so I was able to reach higher speeds quickly.
Both of them worked very well, but i am still unsatisfied, because I couldnt get the exact increase in mileage (because mine is a pretty old maruti without a reserve indicator), and also I dont know whether my economic mode is really good for engine(does the thumb rule "shift the gear down whenever rpm falls" correct).

Now, please comment on my driving habits, am I correct or not?
Are concepts correct? Can you spot any logical errors?
please suggest any ommissions?

Is it always necessary to lower gear when engine rpm is reduced by some reason?

or is it only required when you feel that engine is going to knock?

Please add any more additional points I missed in both cases....

I have experimented all the above said things on a Maruti 800 without any additional parts...

Also tell me a method to check the mileage of a Maruti 800 at home...

Thanks

Pratheesh Prakash

[BunnyPunia]

STYLE 1 :
this is a fairly ok way. but keep one thing in mind that the max fuel efficiency is achieved jus below the rpm where the car pumps out its max torque, as the engine runs most efficient here. never go very low (in speed) in any particular gear. dont strain the engine. for maruti 800, i guess the best speeds in each gear would be :
1st : upto 10-12
2nd : from 10-25
3rd : from 15-30
4th : from 25-45

now i am writin these speeds but keep in mind, if u need to accelerate immediately, shift down to a lower gear n den accelerate, else u will jus end up burnin more fuel. eg : if u r in 3rd gear at 20km/h and need to accelerate immediately, downshift to 2nd n den accelerate. dont jus keep goin on in 3rd. u wil waste more fuel and acclerate less (as comapred to going in 2nd)


STYLE 2
bad style. dont always keep the car in the upper rpm band, especially urs, as it is an old one.
1st : 0-15
2nd : 15-35
3rd : 30-55
4th : 40- upto the speeds the road allows

remain like this. u will have enuf grunt in each gear at the above mentioned speeds to accelerate in and out of traffic.

Q:"Is it always necessary to lower gear when engine rpm is reduced by some reason?"

A:yes, dont jus keep goin on and on in a particular gear if the speed is comin down. eg: u at are 50km/h in 4th and slow down to 25.. and there is an incline, or u with 4 passengers..now jus dont keep goin on in 4th, downshift to 3rd. it will be better for the engine.


Q:"or is it only required when you feel that engine is going to knock?"
A : engine can knock at lower as well as higher rpms dependin on various reasons.


Q: "Also tell me a method to check the mileage of a Maruti 800 at home..."
A: the most accurate way is to do a check from tankful to tankful. but keep in mind, dont jus tank up and drive 30kms and den tank up again. coz there is no way to see that u put in the fuel to the right spot again. so even if u put in extra 100ml, it will drastically change the figures. its better to use up atleast 18-20litres for a more accurate figure. again dont take 2-3 weeks to use up these 20litres, as the fuel will evaporate to an extent and even if 500ml of fuel evaporates in 2weeks, it will change the avg to a large extent

eg : say 313kms in 20litres = 15.65
and 313kms in 19.5litres = 16.05
so u see a change of 0.5 kmpl..

its better to do such an avg check wen u know u wil be driving a lot in the next few days. and keep a check onto the point till where u fill up fuel in the tank, or jus fill up the tank till the point the nozzle automatically stops the 1st time. and wen u drive and tank up again after a few days, again stop fillin the fuel wen the nozzle stops automatically,.

happy motoring.

[prkothan]

chill out man. No one can do magic. If you 14-16 in 800 it should be fine. If its second hand vehicle, you never know how the previous owner ripped it. Hence milage is bound to be low. There is only one solution..
Work smart/hard and improve your earnings. This the positive way of solving your problem.

[pratheesh]

But what if i just touched the brake and the speed does not change drastically (say from 50 to 45) and the engine still runs smoothly...

[revtech]

Originally Posted by pratheesh

But what if i just touched the brake and the speed does not change drastically (say from 50 to 45) and the engine still runs smoothly...

no if theres a very sllight reduction in speed like the one you mentioned then there is no need to down shift you can continue in the same gear.


Rev

[Zappo]

Originally Posted by pratheesh

But what if i just touched the brake and the speed does not change drastically (say from 50 to 45) and the engine still runs smoothly...

Hey heyyy... you misunderstood what you read earlier. It is not as if you have to shift down at every drop of the speed. This is something that you will get a feel of as you keep driving. The engine noise, its response everything will tell you when to shift up or down. If you are on 4th and the speed drops marginally from 50 to 45 you definitely DO NOT need to shift down.

The idea is to ensure that you do not "lug" your engine. If you feel that although the engine is not stalling but the speed has fallen to an extent where you feel like the engine is not picking up fast enough it means you need to shift down. Remember, do not step on the accelerator with a heavy foot to accelerate faster. That only burns excess fuel; shift down and then accelerate. Once the speed has built up you can shift up once again.

A related piece of advice... Since you have this idea ingrained in your mind that you should try to stay at the highest possible gear to save fuel you will commit a mistake that many do. You will be reluctant to shift down even when the speed falls, to the extent that even if you feel that engine is groaning (just before it begins to stall/knock) you will try to slip the clutch and gain speed rather than shift down. This not only burns excessive fuel but also erodes the life of your vehicle's clutch. Use the clutch minimally.

In fact if you are driving at a good speed and feel like you are gaining too fast on a vehicle ahead do not get on that clutch and the brake. Just release the accelerator. Your engine is a fantastic brake. If you want further deceleration just jab you brakes for split seconds once or twice... It increases the clutch life and raises the FE as well. The brake light coming on for a brief while also warns the vehicle behind you that you may apply full fledged brakes soon and thus serves him an advanced warning.

[Shan2nu]

Style 1 - Objective is to decrease fuel consumption
---------------------------------------------------

I commonly drive in this style, because i am from a lower middle class family, and petrol costs me a lot.
Well, in this mode I shift up the gears rapidly (though without jerking),when the engine reaches the minimum (I mean the engine runs smoothly without knocking) rpm of that gear.
As a result i am able to reach the Top gear easily and able to ride at the lowest speed as possible.
Whenever engine rpm reduces (brakes!!!), i refrain from shifting down the gear, and shifts down only if I feel that the engine is going to knock.

Please read the owner's manual of the car you're going to drive. The optimum shift points for that particular model would have been mentioned in it.

Shifting at the same rpm in every car you drive, will not help in any way.

Style 2 - Objective is to decrease the time of travel
-----------------------------------------------------

Often used when I am toooo late. During this mode, i raises the engine at a gear till it start to moan, so that i could accelerate (I presume that you accelerate better at lower gears than at top gears) to a maximum limit. By doing so I was able to reach higher speeds quickly.
Both of them worked very well, but i am still unsatisfied, because I couldnt get the exact increase in mileage (because mine is a pretty old maruti without a reserve indicator), and also I dont know whether my economic mode is really good for engine(does the thumb rule "shift the gear down whenever rpm falls" correct).

Now, please comment on my driving habits, am I correct or not?
Are concepts correct? Can you spot any logical errors?
please suggest any ommissions?

Is it always necessary to lower gear when engine rpm is reduced by some reason?

or is it only required when you feel that engine is going to knock?

Please add any more additional points I missed in both cases....

I have experimented all the above said things on a Maruti 800 without any additional parts...

Also tell me a method to check the mileage of a Maruti 800 at home...

To extract the maximum out of your car, you will have to revv the engine to the point where it produces peak power. If your car doesn't have a tachometer, check the car manual for the max allowable speed in each gear and make sure you don't over do it.

At this rate, the fuel efficiency of your car will be at it's lowest.

A downshift is only required when the engine rpm in the present gear drops to a level where the engine starts to knock/shudder. However, donot wait until this happens, as you get used to the car, you will know when to downshift.

To check your FE. Fill the tank up, reset the trip meter, wait until the fuel gauge shows empty again, fill the tank once more, substract the number of litres filled from the number of litres the tank can hold, compare it with the number of kilometers travelled on the trip meter and you'l get your FE.

EG: If a car has a tank capacity of 40ltrs, you fill it up, travel 500kms, fill it up again and find that the car has taken up 20 ltrs. All you have to do is divide 500 by 20 = 25kmpl.

Distance travelled / litres consumed = kmpl.

PS : Always fill gas early in the morning, when the fuel is dense. You will get a little bit more for your money.

Shan2nu

[DCEite]

Originally Posted by Shan2nu

To check your FE. Fill the tank up, reset the trip meter, wait until the fuel gauge shows empty again, fill the tank once more, substract the number of litres filled from the number of litres the tank can hold, compare it with the number of kilometers travelled on the trip meter and you'l get your FE.

I didnt get you. Why you have to subtract? You can straight away divide the trip meter reading by the number of litres.. isnt it? Since the number of litres filled in second fillup is exactly the number of litres consumed since the First fillup.
I hope i am not getting confused

[Zappo]

Originally Posted by dceite

I didnt get you. Why you have to subtract? You can straight away divide the trip meter reading by the number of litres.. isnt it? Since the number of litres filled in second fillup is exactly the number of litres consumed since the First fillup.
I hope i am not getting confused

No, you are not getting confused. You are right, you need not subtract. Just divide the Liters filled by the trip-meter reading to get the distance travelled.

[Shan2nu]

I didnt get you. Why you have to subtract? You can straight away divide the trip meter reading by the number of litres.. isnt it? Since the number of litres filled in second fillup is exactly the number of litres consumed since the First fillup.
I hope i am not getting confused

Yo're right. No need to substract. My mistake.

Shan2nu

[DCEite]

Shan2nu, rather than waiting the tank to go to empty mark, you can run the car after first fillup for say 50km, and then divide the litres filled(second fillup) by km(50). This will be more accurate in my opinion, since empty mark is'nt always accurate, and there is always fear of running out of fuel. Whatsay.

[filcord]

Originally Posted by dceite

Shan2nu, rather than waiting the tank to go to empty mark, you can run the car after first fillup for say 50km, and then divide the litres filled(second fillup) by km(50). This will be more accurate in my opinion, since empty mark is'nt always accurate, and there is always fear of running out of fuel. Whatsay.

Calculating mileage after only 50km run is not going to give you a correct reading.The distance is too short and may not be representative of your average running. Therefore you should run at least 200 km since such a long running will include many more types of road and driving conditions, and will give you a truer picture of your actual FE

[Shan2nu]

Shan2nu, rather than waiting the tank to go to empty mark, you can run the car after first fillup for say 50km, and then divide the litres filled(second fillup) by km(50). This will be more accurate in my opinion, since empty mark is'nt always accurate, and there is always fear of running out of fuel. Whatsay.

The fuel gauge need not be accurate at all. When you fill gas again, all you need to do is, look the number of litres filled and then divide the kms travelled by that fig.

If you fear that the car might stall, check the reading just before it hits empty.

But, always calculate litres cunsumed by looking at the meter at the gas station and not your fuel gauge.

Getting accurate figs is impossible as even trip/odo meters have error in them.

Shan2nu

[tsxei]

Don't bother yourself with techniques when you are driving in the city most of the time. This is because no matter how hard you try to change your driving style, if there is lot of traffic on the road, you will get ****ty mileage. Just try to find a reasonable route with least traffic so you can drive with least number of stops/gear shifts and try to stay at the highest possible gear without lugging the engine. The higher the gear the lower the engine rpm and hence lower fuel consumption. And if you do have to stop, try to anticipate the stops and slow down to a stop rather than racing to the stop and hard braking. In general smooth launches and smooth stops will save some fuel. Besides the driving style there are other ways to reduce fuel consumption - don't miss any of the factory recommended service schedules, maintain proper tyre inflation, don't carry unnecessary load in your vehicle.

[turbo_lover]

btw - the old maruti never had a trip meter...

Style 2 - Objective is to decrease the time of travel

i dbout that is a good method..if you want to go fast in in the city you are required to shifting to quicker lanes, not brake as often and u can go quick in 4th gear driving at 60...shifting gears doesnt help unless your draggin every motorist on the road...dont need to strain your engine ...