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Old 18th December 2008, 21:52   #1
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Default Does engine CC / power matter for steady reverse on incline?

There’s an incline before the parking space I have. (apprx 1.5 - 2 feet above ground) Sometimes I enter the parking space in reverse to prevent taking reverse while coming out of parking. It’s Alto.

What I notice is that, if from standstill I have to pull the vehicle up on that incline while preventing it from moving forward, then I have to race the engine more as I release the clutch but though I race it more it does not move so easily. And then eventually at one point even though I am slowly increasing the accelerator, it gains fairly good speed in no time in reverse.
I notice others pulling their vehicle up on similar incline in adjacent parking spaces very slowly! Is this because Alto has just 800 CC engine?
Other members have Santro or higher CC models like Ford etc so do they get better power and steady control while pressing the accelerator.
Or is it that I need to be more in tune with the clutch-accelerator operations.
Thx.
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Old 20th December 2008, 12:43   #2
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Engine power is adequate for Alto. It is your clutch which engages the transmission. You need to practice the "bite" at which it will transfer the power without raising the engine rpm. It takes a bit of getting used to. It varies from car to car.
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Old 20th December 2008, 14:08   #3
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practice make driver perfect.
alto has adequate power. after some more time, it will be easier for you.
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Old 20th December 2008, 14:18   #4
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this has nothing to do with the cc/ power of ur car
alto has enough power , and also the reverse gear ratio is lower than 1st , so it would be easier for the car do the same incline in reverse than first, u just need to practice,

Last edited by siddartha : 20th December 2008 at 14:19.
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Old 20th December 2008, 14:28   #5
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well i dont deny that 800 cc in alto does make this a bit difficult as compared to other cars. but the difference is not as huge as you think, especially when compared to cars like santro, the difference is not much. yes, if its a diesel car, it will be much easier as they have much higher torque which matters the most in such situations.

practice the acc-clutch modulation.
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Old 20th December 2008, 14:33   #6
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Quote:
and also the reverse gear ratio is lower than 1st
Which means that the engine revs have to be higher to the same speed in reverse as forward in first.

This is why you have to race the engine more.
Quote:
but though I race it more it does not move so easily. And then eventually at one point even though I am slowly increasing the accelerator, it gains fairly good speed in no time in reverse.
It sounds as if you are letting the clutch slip too much.

Yes, you do need "to be more in tune with the clutch-accelerator operations.". As Siddartha says, practice makes perfect.

You need to perfect this technique --- the alternative would be wearing your clutch out!

An alternative is not to do the 'hill start' but to 'hit the ground running' by having the car moving for a few yards before coming to the slope.
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Old 20th December 2008, 16:20   #7
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Thx friends..yeah I should practice it more with such situations.
Just wish to understand what is exactly meant by
Quote:
the reverse gear ratio is lower than 1st
and also what is meant by
Quote:
letting the clutch slip too much
Does this mean I am releasing the clutch more or not that enough.

Thx
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Old 20th December 2008, 22:32   #8
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the reverse gear ratio is lower than 1st = for the same car speed, the engine revs will be higher.

letting the clutch slip too much --- not full engaging the clutch. Sometimes if we are feeling a little nervous about stalling on a steep slope we might rev the engine too much, compensating by depressing the clutch slightly.

I hope that helps: someone else putting in different words would be good too.

It is a perfectly valid technique in first or reverse gear to control car speed with the clutch, but it should be used sparingly. A fully engaged clutch (no foot on the peddle) does not wear, nor does a fully disengaged clutch.
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Old 21st December 2008, 16:31   #9
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Usually in most of the cars wheels don;t rotate at the same speed (rpm) of the crank shaft at 1st, 2nd and 3rd gears. 4th and 5th gears are a different topic where you get more speed, better fuel efficiency but a poor pulling power.

Reverse gears always have the highest gear ratio ie., the number of turns the crank shaft should turn for one full rotation of the wheels is high. That's the reason you get a lot of pulling power in reverse than in first. If you want to experience take your Alto to an empty road or open field and try just releasing the clutch without any acceleration and press try with acceleration as well. You will see that the car bites the road but can't go faster as in front gears.

Having said that on slopes even the reverse gear ration wont be sufficient to pull the entire load of the vehicle there you need to start maneuvering with your clutch. Imagine that you are going to further increase the gear ration so that you can pull more load caused by the inclination as well, which can be accomplished by not letting clutch go fully rather releasing it only until the wheels starts rotating and engine doesn't lug. As raj_5004 mentioned Diesel engines have higher torque on lower rpm's hence this steps are quite easy. But for petrol you need to raise the RPM a bit to keep up the torque.

When I was having Matiz I have to raise the engine for getting it into my parking lot but after switching to Palio Diesel I don't even touch the accelerator now for parking.

Hope this helps
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