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Old 11th January 2005, 15:01   #16
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do you know people who alter gear ratios? how safe is it?
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Old 11th January 2005, 15:15   #17
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Quote:
do you know people who alter gear ratios? how safe is it?
If a person knows what he's doing, altering your gear ratios will make your car handle corners better and your acceleration coming out of corners will be better.

But there's no such thing as a perfect set of ratios, F1 and WRC cars have their gear ratios tampered with, for each and every GP, Rally. Even their top speed depends on the track.

In a straight line though, gear ratios can only increase the rate of acceleration through the gears, but you maynot see much improvement in your 0-100 timings.

Shan2nu

Last edited by Shan2nu : 11th January 2005 at 15:17.
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Old 11th January 2005, 18:49   #18
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Hey Shan2nu,

got the gear ratios. In order they are
3.908
2.158
1.345
0.974
0.829

final ratio 3.867

im running 195/60R14 tyres. i did a brief excel working, the speedo is showing 60kmph instead of 57. an error i can live with ;-)

Thanks dude!!!

btw, what do you do?

Rahul
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Old 11th January 2005, 19:02   #19
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Yeah it's showing 57, which means that your car has a speedo error of 4%. 100 will actually be 96. That's pretty reasonable i guess.

But if you test your car with a GPS device, it might show you 55-56 kmph, coz there will be some diff between therotical and practical results.

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btw, what do you do?
Me? I'm a fine arts student.

Shan2nu
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Old 11th January 2005, 21:46   #20
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the palios before the Nv had this problem due to which people used to think that the car was giving bad FE figures.
the fact was that the pre-NV palio's had speedo's calibrated for diff tire specs.
so mabbe ur petrs/siena' s have this problem
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Old 12th January 2005, 12:50   #21
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per this math, my speedo seems to be right, 2000rpm, 40kmph, calculated 41kmph OK


my 224/192 still unsolved, may be the gear is intermittently meshing?! Yesterday I also saw when I breaked at 40 indicated speed, the speedo actully rose to nearly 60 before it dropped, i'll get it checked this time when i go to service
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Old 12th January 2005, 13:17   #22
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my 224/192 still unsolved, may be the gear is intermittently meshing?!
Do some more tests before you come to any conclusion.

I think the speedo, odo and tripmeter, all run on the same principle and are interconnected. I don't think only the odo or tripmeter can have error. If your speedo has no error, your tripmeter can't possibly have that much error.

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Yesterday I also saw when I breaked at 40 indicated speed, the speedo actully rose to nearly 60 before it dropped,
I have no idea how this can be possible

Shan2nu
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Old 12th January 2005, 15:40   #23
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Shan2nu, It is actually fuelling my doubt that the connection at the worm end is intermittent.

Here is what i guess (only guess, not sure), I may be actually be driving at 60 but the speedo was showing 40 as it only had a partial contact, inertia of breaking could have triggered it to mesh fully, this may momentarily indicate the actual speed.
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Old 12th January 2005, 19:39   #24
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Hey DRC,

Try going much faster, say about 100km/h and listed for any grinding or whining from behind the dash.
If its a worm gear thats slipping then i dont think there would be any noise other than an occasional click if at all.
Im not sure of exactly what the system is behind the dash, but this would be one test to run.

Also, if your accelerating and the speedo just stops rising at a certain speed (maybe 40-60) you could be assured its a slipping mechanical connection somewhere.

cya
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Old 26th January 2005, 03:44   #25
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Hey DRC,

Did you get the problem fixed yet?

Let us know.
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