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I have had KIA diesel half a year. On motorway I can drive 80 km/h, and consumption of fuel is about 4.5 l/100 km.
When I rise speed up to 120 km/h, the consumption is almost double.
On curved sand road consumption is triple, and speed is about 50 km/h.
On asphalt KIA uses fuel 3.5 litres/100 km with speed of 50 km/h.
I pay quite much atention, how I burn fuel on road nowadays.
But I live in Helsinki, and my trip to summer cottage is 150 km. It takes 2.0 hours to drive. If I start from Helsinki during rush hours, trip takes one hour more.
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If I drive 20% over speed that 150 km, I am in destiny 10 minutes earlier.
That is theory about speed and fast cars.
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