Once underway, the real eco-driving
can begin. Some eco-driving proponents say the driver should shift up from one gear to the next at no more than 2,000rpm. While this might make sense in light traffic or on smooth, flat roads, the reality is some more engine revs may be required for the driving conditions. What we can do to minimise fuel consumption is change up through the gears as soon as possible. Petrol and diesel engines require different engine revs for any given situation, but common sense and a feel for the car tells the DIAmond driver when to change up to best balance progress with economy. Once in a higher gear, some eco-
driving gurus also reckon it’s wise to leave the car in as high a gear as possible at all times. Again, experience proves this is not always the most frugal way to drive, as it can put undue strain on the engine and transmission. Allowing the engine to labour also doesn’t make for safe driving. Among eco-drivers, there’s a group
called hypermilers, who see maximum fuel economy brought on by driving style as the ultimate goal. Hypermiling owes much toWayne Gerdes, who is known as the father of hypermiling and has done much to publicise this style of driving in the US. Gerdes and some of his followers go
to extreme lengths to gain the best fuel economy, claiming to see improvements of up to 60% in the fuel economy of their standard cars over the manufacturers’ official figures. They practice coasting and ‘drafting’, though not always in everyday driving conditions. Neither of these techniques can be regarded as safe and one of the UK’s leading hypermilers, Karl Dyson of
www.hypermiler.co.uk, is quick to point out these methods are questionable and should not be used. Many hypermilers call coasting a ‘forced
A car in fine fettle rewards its driver with good
economy and reliability
auto stop’ (FAS) where the engine is switched off and the car is allowed to roll to a standstill. In a modern car, the FAS method means forgoing power steering and effective braking, so it can only be seen as dangerous. Dyson says: “Safety must always
come first. Driving for the best economy, however, is easily compatible with safer driving as both require the driver to leave more time and room to think and manoeuvre. By giving yourself more time and road space, not only is your driving safer it gives you greater time to plan a more fuel efficient path through traffic.” Coasting with the gearbox in neutral but
the engine still working is another option, but not one to be recommended, as the driver still does not have complete control of the car. Coasting also offers no real
April / May 2011 | driving
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68