How to get better mpg?

[Saracen]

It's all been said, really, but my 2p ...

- check tyre pressures. it does matter.
- gentle acceleration/braking
- read the road and anticipate
- it seems to help ... keep windows closed. Avoid aircon, too.

[Butcher]

It's all been said, really, but my 2p ...

- check tyre pressures. it does matter.
- gentle acceleration/braking
- read the road and anticipate
- it seems to help ... keep windows closed. Avoid aircon, too.

Windows closed definitely helps; an open window creates a lot of drag and you have have burn fuel to overcome that.

[Saracen]

Windows closed definitely helps; an open window creates a lot of drag and you have have burn fuel to overcome that.

Yeah, I understand the logic. I've just never seen hard evidence and my own tests aren't extensive enough to be conclusive.

[Bagnaj97]

Windows closed definitely helps; an open window creates a lot of drag and you have have burn fuel to overcome that.

Clearly for MPG you want windows closed and aircon off, but sometimes it's just too hot and you have to do something. I've read in the past that ~30mph is a transition point - below that it's more economical to have windows open and aircon off, above that aerodynamics are more important and it's more economical to shut the windows and use aircon. I can't find a source, and presumably the exact speed will depend on the aerodynamics of the car in question, but it sounds sensible.

Of course you could keep the windows shut and use the fans/blower without aircon...

[Zak33]

Yeah, I understand the logic. I've just never seen hard evidence and my own tests aren't extensive enough to be conclusive.

front windows open a tad aren't too bad

rear windows are a bloody nightmare... open to slow down ;-)

your eardums can tell you....the buffeting and the cabin pressure thrumming tells you,


Tyre pressures. In some cars the handbook states higher tyre pressures for genuine advantages. I run most of my cars highers than normal anyway .. I prefer the harder tyre walls particulalry on the rears, but they do lose a little grip in some conditions.

accelerate with about 40% throttle up to the speed you want then feather the throttle

dont fanny around really slowly building your speed... the fuel improvements are minimal compared to the time you lose in your life going no where

the best thing for fuel consumption though is your eye sight and your brain

traffic prediction....lift off WAY before the roundabout and coast (IN GEAR,.,.,never in neutral) and just roll towards it... . you;ll soon realise that you end up at the roundabout still needing the brakes!

NEVER leave a roof rack on! Ever.

but don't be tempted to drive like a vicar every day as all modern diesels hate it...and it'll cost you in fuel anyway when you then have to regen it and rev the nuts off it for 30 minutes to clean it out.

I'd rather see you doing 60 % throttle and getting it warm fast.. going at a proper speed..... and then improving your driving prediction and using the brakes less

don't forget... brakes cost you too......

use them less and you WILL use less fuel.

[Xlucine]

After eeking out the miles in my EV a while ago on a (for an EV) long trip, I found that aerodynamics play a far bigger role than I previously expected.

I found that going over 50mph and you start drastically losing efficiency. My idea was to nip in behind a lorry and get a bit of slip streaming going, but if you're limiting yourself to lorry speeds, you never catch up with one to slot in!

In my more fuel-hungry RS the big impactor has always been acceleration - not even aggressive acceleration, just slowing down for turns or traffic lights are a killer. Stonking it along at questionable speeds doesn't seem to have a major impact - maybe it's a more slippery car than the EV.

But yeah, as above for going on a trip.

- Reduce your weight, swap your space saver for a break down sub and a can of goo.
- Check your tyre pressures are correct
- Find a reputable garage with a Hunter tracking system and check your wheels are all straight (it's amazing how much fuel dragging a tyre sideways will use).
- Check your thermostat is working correctly, as engines need to be maintained at a correct temperature to be efficient

IMO the tyre goo is a false economy. A tyre with a hole in it can be repaired, a tyre with goo in it can't. And when you're replacing one tyre, you need to replace the other side of the axle or else the ABS will get upset (diff will get a bit hotter too, if it's a driven axle). Goo is also no good if you hit a curb and damage the rim, with the space saver that's an easy fix

[kalniel]

In my more fuel-hungry RS the big impactor has always been acceleration - not even aggressive acceleration, just slowing down for turns or traffic lights are a killer. Stonking it along at questionable speeds doesn't seem to have a major impact - maybe it's a more slippery car than the EV.

Very much doubt it! It's more likely a surfeit of torque. I found the same when I had a torquey large diesel car - it was far less affected by air resistance. Which of course means they should have added a higher gear/run a more economic timing because they didn't need that much torque for the speed!

[Butcher]

IMO the tyre goo is a false economy. A tyre with a hole in it can be repaired, a tyre with goo in it can't. And when you're replacing one tyre, you need to replace the other side of the axle or else the ABS will get upset (diff will get a bit hotter too, if it's a driven axle). Goo is also no good if you hit a curb and damage the rim, with the space saver that's an easy fix

I've had one puncture so far on my car. The goo was useless as it had a huge rip in the sidewall. I had to get recovered to a nearby garage and buy a tyre at some expense (over a barrel and all that). The irony was I was having 4 new tyres put on a week or so later, so I spent a lot of money on a tyre for it to get maybe 500 miles usage tops.

[AGTDenton]

I would add:

Dont use daylight running lights. I disabled mine and saved around 40miles to a tank each fill, I was quite surprised how much they were using.
However, mine are older halogen bulbs, if yours are LED it wouldnt make that much difference.

Set driving mode to ECO mode if your car has it. Sport/Performance drinks far more fuel on acceleration. Cruising is the same, however.

Clean out your car, I often end up with work stuff litterered around the place. But you'd be surprised at just how heavy rubbish and stuff you dont need in the car are. Keep only emergency stuff, and overnight bits if long road trip. Every fuel/hotel stop clear out the rubbish.

Dont leave AC or fans on if you dont need it - wear more or less clothes depending on the temperature.

Turn off sub, or turn down bass on audio obviously not to a level that makes the drive boring, but your ears will soon adjust.

[Dashers]

IMO the tyre goo is a false economy. A tyre with a hole in it can be repaired, a tyre with goo in it can't. And when you're replacing one tyre, you need to replace the other side of the axle or else the ABS will get upset (diff will get a bit hotter too, if it's a driven axle). Goo is also no good if you hit a curb and damage the rim, with the space saver that's an easy fix

Not strictly true. I use Holts Tyre Weld, it doesn't kipper the tyre like some of the OEM stuff. Just wash it out and repair the tyre.

http://www.halfords.com/workshop-too...tyreweld-500ml

You're right about side-wall damage, if you have a blow out or something then no amount of goo is going to help you. But then it comes a trade off. How often, if you maintain your tyres correctly, do you have blow outs? Not driving into things at enough speed to damage things is actually surprisingly easy. If you do, you have to call recovery and likely pay over the odds on getting your tyre replaced at a local garage. But even a space saver does add a lot of weight to a car.

I could never bring myself to remove my space-saver in my last car, but most modern cars don't come with spares any more and now none of mine do. I've been lucky and when the wife shredded a tyre she did so at home so I could just take off and down to the garage for a replacement.

If I was going on a cross-continental tour though, I might consider adding a space saver

[Butcher]

Dont leave AC or fans on if you dont need it - wear more or less clothes depending on the temperature.

On the other hand, if you don't run your AC enough it will lose more gas, so it can be a false economy if you end up paying for more frequent regassing. It;s worse if like mine it has the stupid expensive gas, so can cost over £200 for a regas.

You're right about side-wall damage, if you have a blow out or something then no amount of goo is going to help you. But then it comes a trade off. How often, if you maintain your tyres correctly, do you have blow outs? Not driving into things at enough speed to damage things is actually surprisingly easy. If you do, you have to call recovery and likely pay over the odds on getting your tyre replaced at a local garage. But even a space saver does add a lot of weight to a car.

I've never had a blow out, however the above damage was done at just 30 mph. Hitting a rock does a surprising amount of damage it turns out.

[joshwa]

Well, after driving nearly 3000 miles around Europe, the speed I drove had the biggest impact:

60-65mph and I got 61.9mpg
70-75mph - 52.8-53mpg
75-80mph - 50-54mpg
90-100mph (Autobahn) - 46mpg

Racing around the Nurburgring and doing lots of short journeys, 29mpg

Tyre pressure was checked, tread is pretty decent. Better mpg was had when there was less stopping and starting, and the toll roads don't help with this, so the best mpg was had in the UK, where the lower speed limits also helped.

[bledd]

Slightly over-inflate your tyres, by say 10%.
Remove non required items from the car, they soon add up to extra weight