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Old 11-05-2013, 04:27 PM   #6 (permalink)
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GasDwarf - '13 Volkswagen up! EcoFuel CNG
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Originally Posted by krrcan View Post
How to drive slower, in a efficient way?
Should I just drive at 2300-2700 in third gear, and stick to the speed that gets me?
The idea is that you use the sweet rpm range while accelerating, and in top gear, if possible (that is : if it doesn't mean you'd be going too fast).

You may have noticed that it's possible to get more or less the same fuel consumption at different speeds, despite being in the same gear ?

You might get a nice fuel consumption at a lower speed, and lower rpm than the sweet spot - then get the same fuel consumption at a higher speed but with rpm in the sweet spot.

That's when the better BSFC offsets the extra drag due to higher speed.

With the up! , I need to be around 2500 rpm on the motorway - that's around 85 - 90 kph.
Going slower doesn't mean the fuel consumption drops along with the speed.
FC might actually go up.

If I can follow a truck, I can go slower and have better fuel consumption as there is less drag to overcome, even at the distance that I follow.

As it's colder now, strangely enough I can't go as slow as I used to be able to in summer (warmer = lower density air = less drag).
GasDwarf's fuel consumption :

Last edited by euromodder; 11-05-2013 at 04:37 PM..
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