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The numbers don't seem right even if we consider the external factors such as incline, wind direction.

In the Innova, 100 to 120 increases the revs by 250 RPM but 120 to 140 increases the revs by 200 RPM? The gear ratio doesn't change.

Similarly for the Verna CRDi, 100 to 110 increases the revs by 250 RPM and then 110 to 140 by 500 RPM? If the revs go up by 250 for every 10kph increase in speed, then 110 to 140 should see the revs move from 2000 RPM to 2750 RPM.

Does 1800RPM @ 100KPH make it right? :)
Gear ratio won't change for sure, but viscous coupling till its locked, give or take a few RPMs based on road and wind conditions.

Hyundai Accent GLS 1.6 DOHC (PETROL)

80 KMPH under 1650~ RPM
120 KMPH at 2800-3000k~ RPM

Toyota Yaris Petrol CVT, all figures tested with cruise control and torque pro app.

60kmph - 1000 rpm
80kmph - 1320 rpm
100kmph - 1690 rpm
120kmph - 2030 rpm

This is the first time I've taken the car to 120kph after spending 1 year with it. I must say I am very impressed by the way it masks both the speed and the noise. You'll only feel the speed if there are other vehicles around or by looking at the speedometer. Other than that, I could hardly feel the numerous potholes and suspension joints even at 120!

Reviving a old thread !
My father’s 2010 swift petrol(k-series ) does 80kmph at around 2200 rpm as checked in the morning. Now 80kmph is usually the cruising speed for me and my father and we get good fuel efficiency around this speed. Coming to my query, i drove my friends swift ( same engine and model as well as same year) yesterday and in his car ,80kmph is coming in around 2000-2050 rpm mark. Now i was baffled as how can same car with same engine have variations in rpm considering that both cars are driven with 1 passenger and driver?:Shockked:Also the effort taken to reach 80kmph felt lesser in his car than ours. I am ruling out clutch slipping since clutch was changed 9000kms back and the car is properly serviced at MASS in schedule.

Requesting experienced bhpian’s to share their opinion on this variation and tell me whats the ideal rpm for the swift petrol(kseries-2010) at 80kmph and 100kmph.

Thanks in advance:thumbs up

Two possibilities come to mind
1. Are the tire sizes different??
2. The tachometer or speedometer calibration could be slightly different. The error is around 5% and it's possible for an old car to have that different values shown.

A better test will be 80kmph (as indicated by a gps based speedometer app in your phone) and rpm numbers read directly from a OBD based app (eg Torque)

Note: Load also shouldn't impact rpm numbers

Honda Accord 2014 (2.4 I4 CVT)


60mph - 1800rpm
70mph - 2000rpm
80mph - 2300rpm


The car gives a gas mileage of around 27 mpg in the city and 30 mpg on the highways

Hyundai i20 1.0 liter turbo Sportz IMT
achieves 100 kmph @ 2300 rpm in 6th: and 90 @ 2100

While in 5th gear 90 comes @ 2500 rpm

Lexus RX350 - naturally aspirated 3.5 V6 100 kph @ 1600 rpm @ 8th gear.

Here are the engine RPMs at 6th gear (AT) with a 2.5 NA gasoline engine in my 2012 Fusion:
65 mph (105 kmph) @ 2000 RPM
80 mph (128 kmph) @ 2500 RPM

Tata zest 2016 diesel automatic, 90 ps, Fiat 1.3 multijet
80 kmph - 2100 rpm
100 kmph - 2600 rpm
120 kmph - 3100 rpm
All rpms in fifth gear, quite high for a diesel.

My 7-speed Vento TSi and 5-speed Elantra CRDi both have the same final gear ratio!

70km/hr at around 1500/1600RPM
~95km/hr at 2000RPM
100km/hr between 2000 and 2100RPM
120km/hr at 2500RPM

I think it's pretty sweet that a 1.2L turbo-petrol shares the same ratio as a 2.0L turbo-diesel. More than it's performance (the Vento does outperform the Elantra), I think the cruising characteristics help mask it's small displacement!

Out of curiosity, does anyone know what a G20 BMW 330i/2021 Merc C200's engine RPM would be at cruising speeds?

True i notice something similar in my 90ps sx4 and find it quite high for a diesel, Would have preferred it to be more relaxed for high speed cruising.

Here are some figures for my Chevy Cruze 2012 (150 bhp) AT-

5th gear-
* 60 kmph ~ 1100 rpm (TC locked up)
* 80 kmph ~ 1600 rpm (TC locked up)

6th gear-
* 80 kmph ~ 1300 rpm (with TC may or may not be locked up, technically rpm should be 1250)
* 100 kmph ~ 1500 rpm (TC definitely locked up)

This makes Cruze one of the most comfortable cruisers. Theoretically it can do 200 kmph @ 3000 rpm, but I haven't tried.

Please note the tyres are upsized (tyre wall), so the speeds are actually True speeds, as speedo error of 5% has been eliminated. Have tested it multiple times using GPS.

Tested VW Ameo 1.5 TDI 5-Speed MT.
It is slightly remapped at 130 bhp and 300Nm, from the usual 110 bhp and 250Nm. That makes it quite fast, and 5th gear a bit overpowered as well. I feel 5th is a bit short to my liking, since the engine is a bit noisy and harsh, not as creamy as the Hyundai's 1.6.

Here are the approx figures-
80 kmph ~ 1750-1800 rpm
100 kmph ~ 2150-2200 rpm

I have a tyre upsize in plan to improve the legs of the 5th gear slightly.