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Old 6th December 2007, 12:37   #1
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Speed & Gear combination for Chevrolet UVA

Hi,

Request anybody who own UVA or has experience on Chevrolet cars to advice me about the optimum speed to shift gears. I usually follow this

on level roads,

1st Gear : 0-10
2nd : 10-20
3rd : 20 -30
4th : above 40
5th : above 60

This is what I used to do in my Santro.

When I do the same in UVA, first 2 gears are ok. But when shifting to 3rd gear, there is a slight jerk. I tried varying the speed between 20-30. Some times its smooth, but gives a jerk most of the times.

Its a new car, less than 1000km. And I dont have tacho in the car.

cheers,
Arun
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Old 6th December 2007, 16:34   #2
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Feel not read the speed

Mod Note : Post edited to remove FONT tags. Please do not cut-copy-paste from other word softwares. It results in a formatting error. Thanks

Hi Arun,
The gear change should not depend on the speed rather it should depend upon the engine state.
Gears are to modify the engine out so that the output power is tunes to meet the terrain requirement.
A Gasoline engine does not have ability to give varying torque and takes some time to pick up speed up (torque is depends on the speed)

The gear box helps to modify the engine output torque which is required to meet the terrain requirements

Try to understand the engine behavior; a Hyundai engine is different from a UVA. You need to understand
- is your engine a high rpm engine (like Opel)
- is your engine a low rpm engine (like Honda)

The torque curve is what this gives; unfortunately GM does not give Torque curves for its models. So you need to guess engine performance and manage it

I personally feel the engine and drive (same with my Bullet).
1. Keep a close tab on mileage this will tell you if you are behaving with the engine properly
2. Try to understand the engine humm.. this will tell you if you are straining the engine (sure you would have observed auto drivers going up a flyover.... closer to the top the sound of engine is just like .... man spare me spare me....) try this over some time only then will you be able to appreciate this point

Summary
Gear Change is to be done with engines ability to provide the required torque and not by speed (the speed limit is for general public and since you have come here you are not really in that category)
The engine sound is a good indicator (in absence of a Tacho)

Try to learn how to hear our engine and change gears

Cheers

Last edited by GTO : 6th December 2007 at 17:50.
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Old 9th December 2007, 12:53   #3
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arunn its not a good idea to drive at such low speeds specially when you are running-in your car.

I would advise you to go through Team-BHP's guide to running-in your car
https://www.team-bhp.com/forum/ownin...r-new-car.html

As for driving speeds, well speedometer is probably not the best choice I would say.
Start getting to know the engine. A single gear can run over wide band of speed. its all about finding the sweet spot.
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Old 9th December 2007, 13:29   #4
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Just read the user manual. All manufacturers provide the optimum shift points (wrt to engine rpm as well as vehicle speed) when driving under normal conditions.

Shan2nu
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Old 9th December 2007, 16:37   #5
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Quote:
Originally Posted by Shan2nu View Post
Just read the user manual. All manufacturers provide the optimum shift points (wrt to engine rpm as well as vehicle speed) when driving under normal conditions.

Shan2nu
Yup! Would like to add that don't pay too much focus on the technicalities. The thing to keep in mind is try not exceed 90-100 kmph before first 2k and too ensure the engine, gearbox gets worked out in the city i.e. a mix of city and highway driving!

Elito

Last edited by Elito11 : 9th December 2007 at 16:38.
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Old 9th December 2007, 16:48   #6
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Tell us

You are now the resident expert, you tell us where the shift points are (just do not over rev it until it's run in a bit, okay?)

Third gear is a little notchy on a lot of vehicles. You will see some write ups on this in this site. There are some technical reasons for this that I can not remember...anybody help out here?.....I would give it a little run in time and see if the problem diminishes. Coax it into gear a bit for awhile.
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Old 10th December 2007, 23:01   #7
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Thanks for the all good advice..
GM dont give any speed details in the user manual. The documentation need lot more improvement.
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