Fuel Savings: Based on Newsletter Challenge (07/17/07)

In Australia I believe the temp of the fuel being delivered is taken into concideration, and the price varied according to its temp, not sure of the facts but vaguely remember some fuss about in the news, and I believe the garage owners got there way, it must be the day they lower the fuel price per litre?

For a set throttle opening, all other things being equal, each injection will pump less energy per volume as the fuel expands due to temperature rise. The vehicle will therefore slow down and you will have to increase throttle opening to maintain the original speed.

As you know the road so well, you will do better by planning your driving pattern well ahead. Look as far ahead as possible to anticipate road conditions, silly drivers interrupting your driving etc. Gently trail the the throttle earlier as you approach junctions, bends and jams, accelerate using about 80% throttle to obtain cruising speed reasonably quickly then consciously lift the throttle to go into cruise mode. If the car has a computer on board you will soon know that you will get about 6 to 7 mpg as you accelerate and 200 to 300 mpg as you trail the throttle. Dont floor the throttle on hills, you will eat fuel as you accelerate up a hill, Trail the throttle increasingly as you approach the brow and cruise downhill. Avoid dual carriageway routes with roundabouts, that can lose you 5 mpg an a trip, and so on. Even a slight decline can reduce your consumption enormously at a steady speed. A slight extra touch of throttle at any road condition sucks up the fuel. Think, if I were a cyclist where would I be using most muscle.

hope this helps

In Canada all the fuel pumps at gasoline stations have a notice stating that the gas temperature is assumed to be 15 deg C. The flow is measured by volume and not as a mass flow. If you filled up at the coldest part of the day in winter you might get some advantage, but as the tanks are below ground the temperature is probably quite constant.

As for your idea of heating the fuel this has been tried many different ways, with the most common problem being vapour locks if the liquid vaporizes to a gas in the fuel line. You are better off to get the air entering the engine as cold as possible to make it more dense and therefore more Oxygen. The new cars due however have a mass air flow sensor and will deliver more gas to maintain the fuel air ratio for the least pollution.

The best way to improve gas mileage is to modify your driving habits, easy on the gas peddle and coast whenever possible.