I read this and think I should share it with you;

A petroleum expert has revealed how car owners can get the maximum value for their money each time they fill their vehicles.

Vehicle owners can get more of their money’s worth for every litre of petrol, if they fill up early in the morning when the ground temperature is still cold, says Ramesh Patel who works at the Marian Hill Pipelines, Durban, South Africa.

“Remember that all service stations have their storage tanks buried below ground.

“The colder the ground, the denser the fuel, when it gets warmer petrol expands, so buying in the afternoon or in the evening, your litre is not exactly a litre,” reveals Patel, who has been at the petroleum work for about 31 years now.

The expert says that in the petroleum business, the specific gravity and the temperature of the petrol, diesel and jet fuel, ethanol and other petroleum products play an important role.

“A one degree rise in temperature is a big deal for this business,” he notes, adding that “service stations do not have temperature compensation at the pumps.” Another important tip to cutting petrol cost, Patel says, is to fill up when your tank is half full.

“The reason for this is the more fuel you have in your tank, the less air occupying its empty space.

“Petrol evaporates faster than you can imagine. Petroleum storage tanks have an internal floating roof. This roof serves as zero clearance between the petrol and the atmosphere, so it minimizes the evaporation.”

The petroleum specialist also counsels vehicle owners not to fill up, if there is a fuel truck pumping into the storage tanks, when they stop to buy.

“Most likely the petrol/diesel is being stirred up as the fuel is being delivered, and you might pick up some of the dirt that normally settles on the bottom,” he says.

http://thepmnews.com/2008/09/10/how-to-save-money-on-fuel

I shared this with a couple of friends and they all agreed that it is real. But it will take lot discipline to stop by on my way to work amidst hold up to refill my car.

there some other ways to economize on fuel. The ones I hav noticed and heard are:

-You shouldnt drive like u r racing,
-I heard somethin abt having the right pressure in all four tyres
-When drivin very long distances, its better the windows are wound up. There would be less drag on the car
-The higher the gear, the less work ur engine is doing and the less fuel it burns
-Dont idle ur car for say more than 3 mins, except when u wanna warm it in the morning
-Services ur automobile regularly.

But some cars generally consume more fuel that others, like a 6 cylinder engine would definitely burn more fuel than a 4 cylinder engine

You can now use water as fuel
It's real

have a look

http://milliondollarsreviews.com/topic/how-to-run-your-car-on-water