Driving Economically

The Pheasant

Can anyone give me some tips on driving economically? I drive an '06 Volvo c30 1.8L petrol, delighted with it, great car, but lately it seems to be very thirsty...I keep the tyre pressure at the recommended PSI and I always drive in the highest possible gear but is there anything else I could be doing to maximise fuel economy?

For Forks Sake

The Pheasant wrote: »

Can anyone give me some tips on driving economically? I drive an '06 Volvo c30 1.8L petrol, delighted with it, great car, but lately it seems to be very thirsty...I keep the tyre pressure at the recommended PSI and I always drive in the highest possible gear but is there anything else I could be doing to maximise fuel economy?

Swap it for a 1.6 diesel model

irish bloke

The Pheasant wrote: »

Can anyone give me some tips on driving economically? I drive an '06 Volvo c30 1.8L petrol, delighted with it, great car, but lately it seems to be very thirsty...I keep the tyre pressure at the recommended PSI and I always drive in the highest possible gear but is there anything else I could be doing to maximise fuel economy?

Just don't do 80kph in a 100kph zone like most other people out there driving cars they can't afford.

Supergurrier

Welcome to the Motors section, please don't forget to pick up your complimentary winter tyres on the way out

The Pheasant

irish bloke wrote: »

Just don't do 80kph in a 100kph zone like most other people out there driving cars they can't afford.

Nah unfortunately I have the opposite problem...can't really stay at the speed limit if I have a nice stretch of road
infront of me - probably has something to do with my fuel consumption

Ronnie Beck

http://www.youtube.com/watch?v=THkVciVpmxs

Take what you ant from this. You don't have to go to the extremes he does but basically try to never stop the car. For example if the lights are red up ahead shift down true the gears and roll forward off the throttle in second and hopefully they will turn green when before you have to stop.

I use alot of this stuff driving the van around town as you don't want to stop all that weight. Tried the coasting in neutral thing but it's not good for a big diesel engine to be idling or any diesel engine really.

Ronnie Beck

The Pheasant wrote: »

Nah unfortunately I have the opposite problem...can't really stay at the speed limit if I have a nice stretch of road
infront of me - probably has something to do with my fuel consumption

I've found that all the eco techniques in the worldd make little difference if you've a heavy right foot. You'll need to find some sort of balance. They say to imagine you've an egg on your accelerator pedal. It works wonders for your mpg but gets very tedious after a while.

The Pheasant

Haha yeah I'm definitely gonna have to find a way to cut down the speeding or I won't be able to afford the luxury of speed anymore!

Ronnie Beck

The Pheasant wrote: »

Haha yeah I'm definitely gonna have to find a way to cut down the speeding or I won't be able to afford the luxury of speed anymore!

Hard times man. Doesn't seem that long ago that I didn't know nor care what mpg was.

That coasting in neutral buzz wasn't to bad while I was doing it. You could accelerate quickly up to say 105km/h and coast in neutral down to about 90 and repeat. You end up with the same mpg as you would tippin around real slow at 80km/h. If you want real high mpg the egg technique and low speed is the only way unfortunately. The problem with speed is that the air drag at 100km/h is double what it is at 80km/h.

Ronnie Beck

The Pheasant wrote: »

..I keep the tyre pressure at the recommended PSI

Add 2 PSI all around helps a good bit too. Especially if your doing alot motorway trips.

TheChizler

Ronnie Beck wrote: »

Hard times man. Doesn't seem that long ago that I didn't know nor care what mpg was.

That coasting in neutral buzz wasn't to bad while I was doing it. You could accelerate quickly up to say 105km/h and coast in neutral down to about 90 and repeat. You end up with the same mpg as you would tippin around real slow at 80km/h. If you want real high mpg the egg technique and low speed is the only way unfortunately. The problem with speed is that the air drag at 100km/h is double what it is at 80km/h.

Don't you end up wasting more fuel that way keeping the engine ticking over while in neutral than the energy you would lose through engine friction if you just took your foot off the accelerator?

Constant speed is the key to fuel consumption, any increase in speed results in a relative squaring effect of energy consumed, which you just discard whenever the car slows, every time you cycle your speed you lose a disproportionate amount of energy doing so, plus energy lost to friction. If you keep your speed constant it's purely energy lost to friction.

Ronnie Beck

TheChizler wrote: »

Don't you end up wasting more fuel that way keeping the engine ticking over while in neutral than the energy you would lose through engine friction if you just took your foot off the accelerator?

Not according to this guy anyway. On the flat or uphill at least you still have too inject fuel to compensate for the friction. Your also using less energy required to turn the gearbox which would be a large source of friction. It is a bit more complicated than that too, a bit of an art in itself. Sometimes it's better to roll in fifth going down a hill rather than in neutral if you know your going to have to stop or slow down for something any way.

I've since got a polo so might try it again and compare some mpg figures. After I fix the poxy gear selector leak anyway:P.

Constant speed is the key to fuel consumption, any increase in speed results in a relative squaring effect of energy consumed, which you just discard whenever the car slows, every time you cycle your speed you lose a disproportionate amount of energy doing so, plus energy lost to friction. If you keep your speed constant it's purely energy lost to friction.

Must get cruise control fitted at some stage!
Sometimes an increase in speed on the flat to build momentum to climb a hill in higher gear or in a more efficient rev band can reduce consumption. Approach a hill a 105 and drop to 97 rather than at 100 and drop to 90.
This works well if you time the acceration to put you closer to the car in front so they pull you up the hill.

That guy has a few more video's for different situations.

motorway

coldstart

downhill

uphill

coylemj

Ronnie Beck wrote: »

They say to imagine you've an egg on your accelerator pedal.

Or that there's an egg sitting in a saucer on the bonnet.

After he retired from F1, Jackie Stewart used to do promo work for Ford UK and I saw him once on TV driving a Granada around a test track with a large saucer on the bonnet in which there was sitting a tennis ball. The object of the exercise was to teach people how to drive smoothly and reduce fuel consumption.

dh0011

keep the car serviced
dont break hard
dont coast
I also use dipetane
With these four things i get 41mpg out of a 1.6L avenisi

sogood

I drive a 4.0l and it's a cruiser, not a race car, so I drive it accordingly. I average about 28mpg and sometimes, on long stretches, motorways etc.I use the cruise control and take note of the on board computer mpg (with a pinch of salt) but having said that, driving style is the biggest contributor to good or bad mpg.

But I don't get hung up over it. There are enough causes out there to take away from the pleasure I get from driving and worrying about the needle in the gague is one I tend to ignore.

If it bothered me that much, I'd be driving a Micra. Be sensible, don't be in such a hurry just to catch up with, or pass, the car in front, or to get to the next set of lights/roundabout/junction etc. Relax, enjoy the journey..........

keithclancy

Ronnie Beck wrote: »

Not according to this guy anyway. On the flat or uphill at least you still have too inject fuel to compensate for the friction. Your also using less energy required to turn the gearbox which would be a large source of friction. It is a bit more complicated than that too, a bit of an art in itself. Sometimes it's better to roll in fifth going down a hill rather than in neutral if you know your going to have to stop or slow down for something any way.

Nope, when your engine is in overrun the injectors are shut off, no fuel flows.

Easiest way to explain it is when the engine is slowing down the forward momentum of the car.

Hook up an ODB Reader and see it for yourself