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Old 31st December 2004, 14:36   #16
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Ohh...did I forget to mention that I am not an expert :( But I do know little bit about IC engines, gearing etc.
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Old 31st December 2004, 14:53   #17
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Quote:
Originally Posted by speedsatya
hey rajdoll,
first of all trying to slow down from 100kph only using ur brakes is a not such a great idea.as after sometime ,the brakes will get heated up and cud lose their efficiency.so u cud use engine braking if its not an emergency stop.
like say if u r approaching a toll booth at 100-120kph ,u can lift off the throttle and then shift to 4th from 5th.and at the same time pump ur brakes.in this way u can warn others behind u of ur intentions .and then when the rpm falls below 2500-2000 maybe u can downshift to the next lower gear.in this way u can use engine braking and not lose control also .
but if its an emergency stop then u have to brake .
now for when to change gears so that the engine does not stall....[b]when u dont want to accelerate u can shift from 5 th to maybe 3rd or 4th and wait till the engine is about to stall i.e when the rpm is abt 1000 but the car is rolling due to inertia. and then shift to the appropriate gear.
but if u want to gain speed and u have shifted from 5th to 4th ,then maybe u have to change to a lower 3rd or 2nd gear to accelerate.

rajdoll,
read this.even i am not a pro .but after being here ,i have atleast learnt to say a few things.
cheers,
satya
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Old 31st December 2004, 15:59   #18
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See, the engine is like the heart, it needs to work at a cetrain speed to function. The general heart rate i guess is 72 beats per min. What do you think will happen if the heart starts beat at 30-40 beats per sec? It wont be able to pump enuf blood into the body for a given time, meaning that you will start feeling weak, you reaction levels will come down and if this continues, it will eventaully turn fatal.

The same goes for the engine, it has to run at it's idling speed. Anything below that will make the engine jerk and then it'll just stall.

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Old 31st December 2004, 20:34   #19
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plus there will be load on the engine.. cozing wear n tear n more fuel..
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Old 17th March 2005, 16:50   #20
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Quote:
Originally Posted by RX135
or, do what most truck drivers do. Hit the clutch and disengage engine, let the engine gain higher RPM, engage it. It will be able to accelerate again.
I would not suggest doing that. The trucks gear-boxes are a bit different than the cars. Besides, the truck gearboxes are exposed to a lot of wear and tear because of precisely the technique you've mentioned. This also causes the engine to be overloaded all of a sudden from free-revving state. Its always better to down-shift to accelerate, for long life of the engine as well as the gearbox..

Cheers,
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Old 17th March 2005, 17:23   #21
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Quote:
Originally Posted by man23ish
I would not suggest doing that. The trucks gear-boxes are a bit different than the cars. Besides, the truck gearboxes are exposed to a lot of wear and tear because of precisely the technique you've mentioned. This also causes the engine to be overloaded all of a sudden from free-revving state. Its always better to down-shift to accelerate, for long life of the engine as well as the gearbox..
I would not suggest doing that either :-) What I said, was the crudest alternative to downshifting, if someone is hell bent on accelerating in same gear.
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Old 17th March 2005, 19:44   #22
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Quote:
I would not suggest doing that either :-) What I said, was the crudest alternative to downshifting, if someone is hell bent on accelerating in same gear.
Actually what the truck/bus drivers do is blip the throttle while downshifting. I bet they don't even know what it means but since they've been driving for so long, they kinda figured it out themselves.

Blipping the throttle and releasing the clutch in the same gear won't do any good. You'll just get a slight jerk and the revvs will immediately fall back into place.

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Old 27th March 2006, 19:22   #23
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Example:

Doing 100 kmph wanted to stop due to a traffic ahead at breakable distance.
____________________________
I normally apply the brakes, press the cluth well before the car knocks & shift the gear into neutral. Is it wrong?

Here the suggestion is that we need to apply brake & downshift to 4th gear. While downshifting, is it not that we need to press the clutch. If so, is it that we need to press the clutch, downshift to 4th. Apply brakes again, press the clutch & downshift to 3rd.........................

Confusing

The other query:

When I want to take a U turn & if there is no traffic & suppose Iam in 3 rd gear, I will take the turn with the clutch pressed. Once I complete the turn, I downshift the gear to second & accelerate the car. Is this wrong?
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Old 27th March 2006, 21:51   #24
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Quote:
Originally Posted by Surprise
Example:

I normally apply the brakes, press the cluth well before the car knocks & shift the gear into neutral. Is it wrong?
Its not"wrong". But your brakes would last much longer if you used engine braking to slow you down by shifting donw through the gears.

Quote:
Here the suggestion is that we need to apply brake & downshift to 4th gear. While downshifting, is it not that we need to press the clutch. If so, is it that we need to press the clutch, downshift to 4th. Apply brakes again, press the clutch & downshift to 3rd.........................
No, you can downshift while maintaining a constant pressure on the brake pedal. Obviously you would press the clutch pedal to downshift. And to make downshifts smoother you can blip the throttle just before releasing the clutch. All the above requires some skillful footwork and practice. So start by doing it on an empty road.


Quote:
The other query:

When I want to take a U turn & if there is no traffic & suppose Iam in 3 rd gear, I will take the turn with the clutch pressed. Once I complete the turn, I downshift the gear to second & accelerate the car. Is this wrong?
It is always best to downshift while braking for the turn and before you put any input on the steering wheel.
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Old 27th March 2006, 22:00   #25
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Quote:
Originally Posted by Deeps
Its not"wrong". But your brakes would last much longer if you used engine braking to slow you down by shifting donw through the gears.
If you misjudge it then you can screw your gearbox.
And in price of one gearbox you can buy 10 sets of break pad.
Now new cars coming with disk breaks and all I won't suggest engine breaking to any new/limited experienced driver.
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Old 28th March 2006, 17:25   #26
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Quote:
Originally Posted by Deeps
No, you can downshift while maintaining a constant pressure on the brake pedal. Obviously you would press the clutch pedal to downshift. And to make downshifts smoother you can blip the throttle just before releasing the clutch. All the above requires some skillful footwork and practice. So start by doing it on an empty road.
blip the throttle- what it means?

I really dont understand this method. Request to explain in detail. Eager to try this out.

The other reason that I want to try it out is to bring the car to halt during emergency situations using engine braking in addition to the brake pedal
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Old 28th March 2006, 18:05   #27
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Surprise, go through this: http://www.team-bhp.com/forum/techni...nge-gears.html (How to change gears)

It should answer your queries.

Adya, using engine braking alongside the regular brakes can proove to be a life-saver in certain circumstances as it reduces the braking distances (you probably knew that). Therefore, even for a novice it'd be better to get the hang of it as soon as possible.
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