The things I think of while travelling from customer to  customer…

I’ve noticed that some people look for a “magic” way to improve fuel economy.

Often, it involves adding tablets, or other additives to the tank… but usually at an extra expense…

Why bother?

I don’t see the point in saving, say, $2 per tank, where an additive can cost $1 per tank…

The are many other proven ways of improving your petrol mileage, but many people avoid them.

Why? usually because these methods involve changing driving styles, attitudes, and doing regular maintenance.

Whats the best way of improving fuel economy?

Slow down. It’s so difficult for most of us to do, but its also the most effective way to save petrol.

Depending on your vehicle type, driving at 90kph instead of 110kph can improve your fuel economy anywhere between 10% and 25%

How much time will you “lose” by travelling at 90kph?

At 110kph, you will travel 110Km in 60 minutes.

At 90kph, you will travel 90Km in 60 minutes.

At 90Kph, it will take you 73 minutes to travel 110Km (ie: at 110kph, you save 13 minutes, but it costs you lots more (in extra petrol).

I’ve heard some people disagree that a lower speed saves petrol… The argument goes something like this: by going faster, I get to my destination faster, so I spend less time running the engine, so it gets less chance to burn fuel… so I end up saving petrol.

Of course the argument is false, as its well known travelling at higher speeds means you use more fuel per Km compared to travelling more slowly. The harder you press the accelerator pedal, the more petrol you send to the engine

The ideal way to maximise your fuel economy by driving slowly, is to travel as slowly as possible while you are in top gear… for example: its more economical to travel at 70kph (in 5th gear), compared to 90kph (in 5th gear); but travelling at 60kph in 4th gear is not as economical as 70kph in 5th gear.

The other “simple” way to improve fuel economy, is to maintain correct tire pressure. A correctly inflated tyre has a slightly larger diameter than an underinflated tyre, so each rotation allows it to travel slightly further (and it also runs cooler, and is safer due to better vehicle handling characteristics).

Some people also use “accelerate, then coast” to save even more petrol. I don’t think its worth it. The way it works is you accelerate up to, say 80Kph, then you switch off the engine, and coast until the speed drops to say 40 kph, then you turn on the engine again, and accelerate again…

This works well in theory, but I don’t thinks its practical, and it can be dangerous (it you suddenly need to accelerate).

I believe hybrid cars are more capable of implementing the “accelerate then coast” method, but I think simplest solutions can sometimes be the best.