praji.ooo 0 Report post Posted January 27, 2010 Why all vehicles are getting its maximum mileage at the speed of 45-55 kph...? Is that the company itself making the engine-tuning to thal level... Quote Share this post Link to post Share on other sites
creativebala 178 Report post Posted January 27, 2010 Actually Mileage is the result of getting the engine run to the minimum. Say an Accelerator is like a faucet, you open it more, the tank(petrol) gets empty soon. So if you press it very firmly and make the engine run around 1500rpm-2000rpm, very less fuel will be taken and when this 1500-2000, is kept in topgear, it results in 50-60kmph, so the Best Mileage. Also when you drive faster, the Aerodynamic drag strains the engine and wastes fuel, and it will optimum around 50kmph. So the best mileage. Quote Share this post Link to post Share on other sites
sb-alto 21 Report post Posted January 27, 2010 I think it is the correct gear combination along with that speed which helps FE. If gear shifts are done in between the rev limits rather than towards the end of rev it will strain the engine less and hence less Fuel consumption. 1st gear-10kmph 2nd gear-25kmph 3rd gear-35kmph 4th gear- 45kmph 5th gear- 55kmph These shift speeds actually means that engine runs at mid rpm. So more FE. Aerodynamic drags at high speed is also another cause. If rear windows are rolled up and front windows half up(without ac) then it reduces drag and delivers more FE. Keeping a constant speed of 55-60 in 5th gear helps getting more FE. So its just not about the speed but many other factors as well. Keeping correct tire pressure, clean air filter, good engine oil, less braking and less quick acceleration are other measures to get good FE. Speed limits of 40-50kmph are recommended as it delivers more FE and it is a safe driving speed. Quote Share this post Link to post Share on other sites
