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Old 5th July 2011, 09:49   #31
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Default Re: Help with Rpm vs Speedo Speed

Toyota Innova

Gear Ratios/kph per 1000rpm
1st 3.928/7.71
2nd 2.142/14.15
3rd 1.367/21.69
4th 1.0/30.31
5th 0.851/35.62

Final drive 3.909:1

Source: Indiacar.com
TOYOTA INNOVA 2.5 D-4D
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Old 5th July 2011, 12:43   #32
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Quote:
Originally Posted by ecenandu View Post
Toyota Innova

Gear Ratios/kph per 1000rpm
1st 3.928/7.71
2nd 2.142/14.15
3rd 1.367/21.69
4th 1.0/30.31
5th 0.851/35.62

Final drive 3.909:1

Source: Indiacar.com
TOYOTA INNOVA 2.5 D-4D
Thanks ecenandu, Got these values -
Engine Rpm / Gear Ratio / Final Drive Ratio X Wheel Circumference (Inches) X 2.54 / 100000 X 60 :

(1000 / 0.851 / 3.909 ) * 80.519 *2.54/100000 * 60 = 36.88
1500 RPM -> 55.32
2000 RPM -> 73.76
2500 RPM -> 92.2
3000 RPM -> 110.64

I see 60 & 80 for 1500RPM and 2000RPM. Maybe reading error while driving! Otherwise, it appears to make sense. I will try to check the speedo little more closely
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Old 12th July 2011, 15:33   #33
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Default Re: Help with Rpm vs Speedo Speed

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Originally Posted by samm View Post
This is what I saw on my Innova, all data on 5th gear. Sorry I dont know the gear ratios, so didnt do any calculations.
a) 1500RPM-> 60KMPH; 2000RPM->80KMPH; 2500RPM->90KMPH. This gives me a overall ratio of 1500/60 = 25. I expected, that the car will reach 100KMPH at 2500RPM (=100*25)...
b) sometimes, the rpm goes to 1750 or more, with the car speed at around 60KMPH. Seems like it is not linear?
Any help is appreciated! Thanks!
Dear samm isn't it contradicting ? (bold underlined)

Please understand at a given RPM and given Gear, vehicle speed has to be constant NO MATTER what may be the load, incline etc. etc. may be .

This is a mathematical relationship so does not depend upon torque curve or Bhp delivery etc. also.

Cheers
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Old 12th July 2011, 16:13   #34
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Default Re: Help with Rpm vs Speedo Speed

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Originally Posted by sanagg1 View Post
Dear samm isn't it contradicting ? (bold underlined)
Right, that was what I too understand, unless clutch slips, which is not possible for a new car.
With the gear ratios that ecenandu provided, it appears more logical. Seems like there is a parallax reading error from my side. Also, I would have approximated from both rpm and speedo, while driving. Have to check it little more closely.
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Old 12th July 2011, 20:42   #35
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Default Re: Help with Rpm vs Speedo Speed

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Originally Posted by samm View Post
This would mean that, for a given RPM, the vehicle speed should be constant?
Also, it would mean that if RPM increases at a given gear, the speed should also increase?
Again, the vehicle speed and the RPM will change in a linear manner?

This is what I saw on my Innova, all data on 5th gear. Sorry I dont know the gear ratios, so didnt do any calculations.
a) 1500RPM-> 60KMPH; 2000RPM->80KMPH; 2500RPM->90KMPH. This gives me a overall ratio of 1500/60 = 25. I expected, that the car will reach 100KMPH at 2500RPM (=100*25)...
b) sometimes, the rpm goes to 1750 or more, with the car speed at around 60KMPH. Seems like it is not linear?

Any help is appreciated! Thanks!
Your ratios are
1500/60 = 25
2000/80 = 25
2500/90 = 27..... obviously wrong, should be 2250 rpm!

1. RPM to speed is linear at any given gear, unless the clutch is slipping

2. In case the tyres are slipping you will not know as the speedometer is connected to the gearbox output shaft.

As speedometer error may be non linear, the best method is to use a GPS to calibrate your speedometer at each 10km interval.

If the RPM or Speedometer are driven by sensor/electronics, the cause may be a loose wire. If it is old style using a drive cable, then it may be a slipping gear.
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Old 18th May 2012, 20:53   #36
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Default Gear-wise Speed & RPM values for non-tacho cars

I have a Swift Ldi and as we all know, it comes without a tacho.

Problem- I don't know if I should engage the 3rd gear at 30 kmph, 40 kmph or can easily take it to 50/60 kmph without hurting the engine.

I'm looking for Gear-wise Speed & RPM values for Swift DDiS from fellow bhpians. I know it'll require some effort but hopefully someone might have some free time on a Sunday and can get this for me.

I'm not certain if I'm the only one who's looking for something like this but in case there are others too, well they can use this thread to get gear-wise speed & RPM values for their cars.
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Old 18th May 2012, 21:25   #37
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Default Re: Gear-wise Speed & RPM values for non-tacho cars

@Fine69, I would suggest that you work out the speeds that you are comfortable with. Maruti Suzuki may suggest certain values in the book, but not every one - rather, hardly anyone would use that as a bench mark.

Another way of identifying the gear-shift point is when you dont lug the engine. i.e., change at the speed that is high enough to avoid lugging. (For more details on lugging, we have a thread on lugging .. do search for it)

Personally, though my cars have a tacho, I use the speedo to change gears.
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Old 18th May 2012, 21:27   #38
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Default Re: Gear-wise Speed & RPM values for non-tacho cars

Quote:
Originally Posted by fine69 View Post
I have a Swift Ldi and as we all know, it comes without a tacho.

Problem- I don't know if I should engage the 3rd gear at 30 kmph, 40 kmph or can easily take it to 50/60 kmph without hurting the engine.

I'm looking for Gear-wise Speed & RPM values for Swift DDiS from fellow bhpians. I know it'll require some effort but hopefully someone might have some free time on a Sunday and can get this for me.

I'm not certain if I'm the only one who's looking for something like this but in case there are others too, well they can use this thread to get gear-wise speed & RPM values for their cars.
The speeds I have mentioned below are done on my Ritz DDiS. Been doing this for an year now which has clocked 56K kms.

I don't think there would be much difference between the Ritz and Swift DDiS so you can try these out once. These gear shifts are when the tachometer is just near 2000 rpm that is when the Turbo boost comes into picture (I know the thread is for no -tachometer equipped cars) This is just for the information.

1st to 2nd gear @ 0 - 20 kmph,
2nd to 3rd gear @ 20 - 35 kmph,
3rd to 4th gear @ 35 - 50 kmph,
4th to 5th gear @ 50 - 70 kmph.

I get a mileage of 20 kmpl constant with this kind of upshifting and downshifting when done in the given ranges does not harm the engine or it does not over rev the engine.
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Old 18th May 2012, 21:40   #39
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Ok, when i said i don't want to hurt the engine i mean what's the limit i can push it to, in every gear, say up to 4k rpm. I'm very comfortable driving with the feedback received from engine noise and speedo however if i could safely (without bothering with the fuel efficiency) take the car upto 50 kmph in 2nd gear i'd want to do that.

So that's the reason to look for gear-wise speed & respective RPM values.

FE is not really something i'm bothered about, all i want is to utilize the rpm range when i know that changing the gear to 3rd at 40 kmph means only to downshift a few seconds later in delhi traffic. So if i knew that i could take the speed upto 50 kmph in 2nd gear and still wouldn't touch the redline then i'd rather do that.
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Old 20th January 2013, 20:49   #40
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Default Re: Help with Rpm vs Speedo Speed

My esteem hits 70 km/hr at 3000 rpm in 3rd gear and 98 km/hr at 2500 prm in 5th. Is that okay ?
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