Question for the clever people

[KiwiBacon]

Dont forget, BSFC maps do not take into account factors outside the mechanical componentry of the vehicle.

Very true, the BSFC plot only concerns the engine. You need to know how much power is required to propel your vehicle (easily estimated from frontal area and drag coefficient), pick that power curve on the BSFC map and grab the best gear.

While the drag force rises with the square of speed (drag at 100km/h is four times the drag at 50km/h) the power required cubes (power to do 100km/h is 8 times the power needed to do 50km/h).

Most people don't realise that it takes around 100 people pedalling to generate enough power to push a car at 100km/h.

[tweake]

If you watch an instantaneous consumption meter you will realise that a low speed (around 40-55kmh) in top gear is dramatically more fuel efficient, but absolutely useless information as I've never yet met anyone who would want to travel long distances at that speed.

see plenty of them around here, even before fuel went up. i'm suprised there is not more or it may be a case of the really tight wads are simply not driving at all.

the silly thing is most of the ones driving slow are generally in vechiles where you have to be in 3rd or 4th gear to go that slow. i would say they proberly use more fuel than if they went a bit quicker and used 5th gear.

[Dr_PC]

Big block would do 4 mpg, small block would do 16 mpg that was on a trip. Race car (Dirt track Oval) with small block would do 2 gallon to the mile Words are the right way round
So 28mpg or better is a saving. Mud tyres at 38psi would knock 30 miles off a tank off gas for my Terrano at normnal running compared to HT pattern tyres. Just keep filling it up