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Old 27th August 2011, 16:18   #1
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Default Cielo -A/T-Concern while overtaking

Dear all,
My dad has been using cielos for a while now(almost 8 yrs now).He has shifted to a cielo A/T now considering ease of use.While driving the car i found that while overtakking the car automatically shifts down and guns forward.I was surprised at this behaviour.Why is this happenning?Can any one throw some light on this.
ram
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Old 27th August 2011, 16:47   #2
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Default Re: Cielo -A/T-Concern while overtakking

It means that someone knew how make a good autobox. Once upon a time

Seriously, it's a good thing. It means that the box knows you're in the wrong gear. If you are in low revs and stab the accelerator, a downshift puts the car in correct gear for the rev range.
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Old 27th August 2011, 16:49   #3
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Default Re: Cielo -A/T-Concern while overtakking

Depending on how hard & fast he presses the acclerator, the car automatically downshifts 1 or 2 gears, eg from 4th to 2nd. It's like you doing the same on a manual tranny to overtake.
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Old 27th August 2011, 16:52   #4
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Default Re: Cielo -A/T-Concern while overtakking

Isn't the Cielo A/T a 3-speed autobox? It is shifting from 3rd to 2nd to put out greater torque. This is since the acceleration demand set at the start of overtaking (acc pedal position and rate of pressing) would have corresponded to higher torque and speed. The top gear in that autobox does not have much torque, especially for fast acceleration.

Last edited by DerAlte : 27th August 2011 at 16:54.
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Old 27th August 2011, 17:21   #5
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Default Re: Cielo -A/T-Concern while overtakking

I had a Cielo ATs.

The basic auto box downshifts very fiercely if you stab the throttle hard. Alternatively, if you press the accelerator gently, the car downshifted less often, and more smoothly.
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Old 29th August 2011, 11:35   #6
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Default Re: Cielo -A/T-Concern while overtaking

I had a drive of arround 250 kms yesterday and i found that when pressed lightly it downshifts to the next lower gear but when pressed hard it goes 2 gears down.It is one great experience altogether.

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Old 29th August 2011, 11:44   #7
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Default Re: Cielo -A/T-Concern while overtaking

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Originally Posted by ram_hyundai View Post
I had a drive of arround 250 kms yesterday and i found that when pressed lightly it downshifts to the next lower gear but when pressed hard it goes 2 gears down.It is one great experience altogether.

ram
It is normal for the all Automatic Transmissions, all of them downshift and upshift based on Accelerator input. Most AT cars come with a Kickdown button at bottom of the Accelerator pedal, when pressed the car goes into max acceleration mode.
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Old 29th August 2011, 13:03   #8
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Default Re: Cielo -A/T-Concern while overtaking

I have driven santro auto as well as wagon r auto.I have never noticed this features with them.
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Old 29th August 2011, 14:52   #9
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Default Re: Cielo -A/T-Concern while overtaking

You mean to say Santro AT and Wagon R AT do not downshift based on accelerator inputs?? When i drove i10 AT(Same transmission as Santro) it did, just like all other AT cars.
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Old 29th August 2011, 16:20   #10
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Default Re: Cielo -A/T-Concern while overtaking

Kickdown is normal behaviour on AT cars. it's also essential since in most older ATs you don't have manual override option.

Maintain even and steady pressure on the accelerator, i.e. drive with a "light foot" and you will not notice this happening much.
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Old 29th August 2011, 18:39   #11
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Default Re: Cielo -A/T-Concern while overtaking

this type of behaviour is common for auto boxes. thats why some of thse more expensive cars have 'sports mode'... thats all it does. late upshifts and early downshifts.
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Old 29th August 2011, 19:01   #12
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Default Re: Cielo -A/T-Concern while overtaking

Kickdown is very much present in i10 AT. However you can kiss smooth acceleration goodbye....the 4 speed auto downshifts at least 2 gears and you're in the 4.5-5k rpm mark immediately.

Net result - upshift again and a consequent slowing up on the initial acceleration.

And the engine SCREAMS "Give up give up " while at it
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Old 29th August 2011, 19:21   #13
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Default Re: Cielo -A/T-Concern while overtaking

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Originally Posted by JishD View Post
Kickdown is very much present in i10 AT. However you can kiss smooth acceleration goodbye....the 4 speed auto downshifts at least 2 gears and you're in the 4.5-5k rpm mark immediately.

Net result - upshift again and a consequent slowing up on the initial acceleration.

And the engine SCREAMS "Give up give up " while at it
actually this cant be helped. A/T originates from huge high torque tall geared ratioed american cars that only drive on highways.... pull out that transmission system and plonk it into an i10 that drives round on indias crowded streets... do the math... what can we expect?
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Old 29th August 2011, 20:27   #14
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Default Re: Cielo -A/T-Concern while overtaking

Quote:
I have driven santro auto as well as wagon r auto.I have never noticed this features with them.
Yes, that's because the 'kitna deti hai?' would be replaced by 'kitna leti hai?'.

The mileage of an engine subject to this kind of treatment would be far lower than its manual cousin, and look bad on the brochure.

Cars are built to different needs, probably the ones you refer to are built for economy?

The only autobox I've driven is a Civic. With due apologies, it's a twit to drive compared to its manual cousin.
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Old 29th August 2011, 21:51   #15
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Default Re: Cielo -A/T-Concern while overtaking

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Originally Posted by naturaldisaster View Post
actually this cant be helped. A/T originates from huge high torque tall geared ratioed american cars that only drive on highways.... pull out that transmission system and plonk it into an i10 that drives round on indias crowded streets... do the math... what can we expect?
We cannot compare with American ATs. Their cars have huuuge engines ( by indian standards ) and a high resultant torque. Hence, plenty of reserve power to catapult the car forward with a shove. 2000cc is considered tiny by them.

BTW, what you said about plonking it into i10 is possible? I doubt. Or, did you say it in a jest?
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