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Old 7th September 2006, 14:20   #16
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Quote:
Originally Posted by vincentt
I guess to extract the best out of the car, gear shifts should be at a point where the higher gear will be able to take the load of the vehicle smoothly. There should not be a drag between the gear change. Higher gear driving does not necessarily mean better mileage.
Well said!.

One mistake many inexperienced drivers do is put the car in 5th gear asap. And when the speed goes down, they stand on the accelerator, instead of downshifting. This is the easiest way to reduce your mileage and engine life
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Old 7th September 2006, 14:48   #17
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Quote:
Originally Posted by WhiteKnight
And when the speed goes down, they stand on the accelerator, instead of downshifting.
BingO!!...
To me FE is a function of accelerator and speed... rather that the gear (gear is the reason for speed)

Take a situation... you are doing 40km/h and you have space on the road to drive at 80km/h.

Now you have 2 ways to do it.
1) First approach
40-50 in 3rd
50-65 in 4th
65-80 in 5th

2) Second approach
40-80 in 5th (as you put 5th asap)

The problems in the second approach when compared to the first:-
1) you take more time (you are left with less time to cruise on the more efficient rpm)
2) you press more on the accelerator i.e pumping in more fuel
3) you strain your engine because you pump in more fuel than it wants at that rpm.
4) you even increase emissions

*these are no scientific study results...

Last edited by SLK : 7th September 2006 at 14:50.
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Old 9th October 2006, 22:44   #18
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Default Optimal Gear Shifts

Ever wondered how to get the most out of your engine's performance? Or, ever admired that guy who shot past in his car like a bat out of bellfry - and then you tried the same "performance" shifting in your car only to end up a major embarrassment with your engine shutting down?!!

Well then, as being a refugee under the former point, I thought we should discuss this - the Optimal Gear Shift Points. Check out this link http://www.datsuns.com/Tech/whentoshift.htm that explains the finer points of shifting.

To contribute to this discussion, my gear shifts on my Swift are designed to keep the car moving swiftly (pun somewhat unintended) at any point of time:

1st gear is changed at 1500rpm/15 kmph
2nd gear at 1500 rpm/25 kmph
3rd gear at ~1650 rpm/35 kmph
4th gear at ~ 1800 rpm/45 kmph
5th gear at ~ 2000 rpm/ > 50 kmph


On my earlier 1.6 Ikon is an altogether different story with the gear shifts very closely resembling the ones in the article
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Old 10th October 2006, 01:57   #19
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WOW nice. I usually do short shift or over burn when doing any drag etc stuff. Mostly short shifting. This may be helpful.

BTW. if i am unable to understand i know that you know whats in that article

Relp Needed!!!

I was seeing at the swift gear ration from its website:
Gear ratios :
1st 3.545
2nd 1.904
3rd 1.280
4th 0.966
5th 0.757

How to convert into the ratios in the artcle 3:1 2:1 ?

Last edited by adya33 : 10th October 2006 at 09:31.
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Old 10th October 2006, 20:59   #20
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Originally Postedby SLK
Well maruti recommends...
1st to 2nd - 10 km/h
2nd to 3rd - 20 km/h
3rd to 4th - 30 km/h
4th to 5th - 40km/h

~~~~~

: this seems to work nearly with my second hand M800;
1st to 2nd - 10kmph
2nd to 3rd - 25kmph
3rd to 4th - 40kmph
4th to 5th - <I wish I had this one>
Grrr....the car wont even take me to 60kmph in the 4th gear .... GRRR, I hate it,
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Old 11th October 2006, 07:30   #21
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Quote:
4th to 5th - 40km/h

Even on my Pulsar, I always upshift to 5th at about 50 KM/H and in the cars I always shift to 5th at about 60 KM/H.


In all the Maruti cars that I've driven, I the gear knocks if I shift to 5th at 40 KM/H. I'm wondering why Maruti is giving these kind of stupid infos just for the sake of FE ?
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Old 11th October 2006, 09:22   #22
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My experience with mileage has been that it does not depend on what rpm i upshift of downshift but how often i do it. in normal city driving in a city like bangalore I hardly go upto fourth gear, but continue driving for as long as I can in third even if I am doing 60kmph because I know that the moment I move into fourth either something will dart across or I would have reached a traffic signal. Another advantage of this that you can make use of engine braking when you need to stop at a signal. I used to drive a Palio 1.2 earlier and in the city thast thing used to give me 12kmpl eay with normal driving when everybody used to crib about its FE. The reason I drive this way is that in most of the new vehicles today both of 4th & 5th are overdrive gears. Logically speaking I should get better mileage when in 4th but I dont..
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Old 11th October 2006, 09:58   #23
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I have a question... please excuse if it sounds stupid!

If I hit a high rpm let us say 2.5-2.8K in 2nd or 3rd gear and reached a speed of 55-60Kph, then instead of going to 4th and then to 5th, can I jump directly to 5th? Since the engine has reached a higher rpm and the vehicle is also moving at a higher speed, will it not help FE if we move to 5th and save all that clutch usage and acceleration/decceleration involved in 4th? Also are there any -ve impacts with this approach?
I've never tried this, but this thought crossed my mind while reading this post.

What say experts?

Last edited by madhav : 11th October 2006 at 09:59.
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Old 11th October 2006, 10:23   #24
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@madhav - You can do this provided you are sure that the 5th gear will be able to take the load with minimal or preferrably no effort. There are no -ve impacts of this.
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Old 13th October 2006, 05:24   #25
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Quote:
Originally Posted by vikram_d
@madhav - You can do this provided you are sure that the 5th gear will be able to take the load with minimal or preferrably no effort. There are no -ve impacts of this.
Are you sure about your information that the gears in cars need not be upshifted in the ascending order like in bikes ?

My knowledge is that downshift can be done in the way you've written.....BUT I still have serious doubts regarding upshifting.
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Old 13th October 2006, 06:33   #26
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Quote:
Originally Posted by madhav
I have a question... please excuse if it sounds stupid!

If I hit a high rpm let us say 2.5-2.8K in 2nd or 3rd gear and reached a speed of 55-60Kph, then instead of going to 4th and then to 5th, can I jump directly to 5th?
I have been doing this on many occasions. But I am not sure whether it is right or not. My own opinion is that when you are at a speed of 55+ in 3rd gear, mocing to 4th gear will be some thing like downshifting. So I feel that there should not be any thing wrong about it.

Still experts' opinion matters.
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Old 13th October 2006, 09:21   #27
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I do this normally on the highways when I touch about 70 in 3rd and jump directly to fifth. Have had no problems so far. But like I said earlier make sure you know that the engine can take the load with no effort.
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Old 14th October 2006, 09:04   #28
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Used to do the same with my Esteem and no issues at all. Follow the same in my Safari & Scorpio as well and no problems whatsoever.

A little bird told me (on whose advice I started this practice) that it makes a difference to the FE. I have never really checked...

Quote:
Originally Posted by vikram_d
I do this normally on the highways when I touch about 70 in 3rd and jump directly to fifth. Have had no problems so far. But like I said earlier make sure you know that the engine can take the load with no effort.
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Old 14th October 2006, 11:19   #29
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Quote:
Originally Posted by WhiteKnight
Well said!.

One mistake many inexperienced drivers do is put the car in 5th gear asap. And when the speed goes down, they stand on the accelerator, instead of downshifting. This is the easiest way to reduce your mileage and engine life
I agree with you that most people are in a hurry to reach the top gear despite not the best condition ( read speed). In way it is always good to work your way through the entire gearbox to get the best FE

I dont skip any gears and go through all of them religiously even if i know i can skip 1-2 gear and go directly to a top gear, which really helps me in building up the momentum that i need for the top gear

Another major FE hamperers are using the clutch as a rest and though not related to FE but, lots of people rest their hands on the gear knob and such long time habit can result in gear ratios getting messed up...so please dont use either the clutch or the GK for resting your body parts
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Old 14th October 2006, 13:31   #30
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Earlier I used to follow sequential upshift of gears......but after grooving I used to ride from 1st to 3rd & 2nd to 4th........after giving initial acceleration say up to 10-15 I used to shift to 3rd & move on fast especially after standstill.......same with 2nd at 40 to 4th.........I started this practice & found that using less gear shift gives relief in city driving........although not observed FE..............

Enjoy..........

Last edited by finetuning : 14th October 2006 at 13:33.
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