What MPG do you get?

The published combined figures for my 1.2 Grande Punto are 47MPG but I checked my trip computer and for the last 300 miles I've managed to squeeze out 52MPG :D That is with a mixture of rural and urban driving (and even a few B-road blasts). I reckon I could get more if I didn't do most of my journeys with a passenger.

I know this is more than I was getting last year, but as fuel prices have increased I've started driving everywhere in 5th, keep a steady speed over my journeys, and avoid harsh braking/acceleration.

As fuel economy becomes more important has anyone else changed the way they drive?

When I had the induction kit on it I usually managed about 33-37 mpg (doing basic rough maths) with combined from my 1.6 Civic. Trouble is that the noise was quite nice so had a tendency to drive everywhere in a gear too low and rev it to about 6700 all the time (yup, basically I drive like a t***).

Anyway my brother has come back and had the kit away (as it's is anyway) and the consumption seemed to be looking really good on dual carriageway/town driving on the way to Bournemouth last week. Trouble is that I think it drinks much more at high revs than before and seems to have really dropped. Haven't checked it in it's un-modified state but hoping to have over 40 mpg at least, maybe 45 if I'm really sensible.

My old man managed to get 72 mpg out of my mum's 1.4 diesel 106 on his B/A road route to work. Basically he pinned it on 60 mph which he said was actually really tough to keep up with in some areas. Still it's a lot better than the 29 mpg he was getting from his Type R (now sold and replaced with a diesel Audi :bigcry: )

My 1.4 Fiesta I've calculated I've been getting 37MPG on motorway runs, not great by any means, but not disasterous either I suppose.

Since I'm switching to diesel I hope to do significantly better!

How do people without fancy computers work out MPG? I always brim the tank and divide whatever I've put in by 4.54. Then use the answer from that to divide whatever my trip says (zeroed whenever I fill up).

E.g if I put 45.4 litres in then that would be 10 gallons and if I'd done 330 miles on that then it would be 33mpg. Not sure if that's the right way to do it but at least if I'm consistent then I know when I've been more economical and when I'#ve thrashed it too much.

Jan, google for Mpg calculator and the first link is a good one to use. My car usually gets about 40mpg but since getting the head gasket done it's managed a record of 44! That's with crap normal diesel fuel. I'm hoping to get 50 out of it on the drive to and from Scotland on motorway roads this weekend and make it there and back doing 750 odd miles on one tank with some shell v power diesel in. Would be great if it were and hdi because i'd probably be able to get close to 1000 miles on a tank!

Top link Daniel, cheers :up:

I tend only to check on the forecourt using my mobile but is nice to do a proper check on it every now and then.

forgot to mention that it's 44 mpg with lots of stop start and b road driving where i'm not able to keep a constant speed. But I still try not to use the brakes and stay in a high gear to keep it as economical as possible.

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Originally Posted by Brown, Jon Brow

As fuel economy becomes more important has anyone else changed the way they drive?

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Well I always driven relatively smoothly since my uni days! If you find that hard to believe its because I got my car at the height of the fuel protest in 2000 so I've stuck to 5th gear whenever possible, shifting at 2000rpm and going over to 3000rpm or more when necessary.

I was quite happy to do 80mph on motorways but thats down to 75 to compromise a bit on speed and efficiency.

The only downer is that I've cut back on taking the scenic route :(

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Originally Posted by Mr Jan Yeo

How do people without fancy computers work out MPG? I always brim the tank and divide whatever I've put in by 4.54. Then use the answer from that to divide whatever my trip says (zeroed whenever I fill up).

E.g if I put 45.4 litres in then that would be 10 gallons and if I'd done 330 miles on that then it would be 33mpg. Not sure if that's the right way to do it but at least if I'm consistent then I know when I've been more economical and when I'#ve thrashed it too much.

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I always brim the tank too. I remember how many litres I put in during the last fill up. Then using google maps work out how many miles I'd done because I remember where I've been. Then work it out from there, pretty similar to you really.

At least my new car should have an inbuilt MPG readout which will be very useful to experiment with to see what driving styles use the least fuel. At the moment it's rough guesswork really.

I brim the tank too and just remember how many miles are on the trip meter and how many litres.

On the little POS that I'm currently driving I've measured 7.5 l/100kms, mostly during daily rush-hour traffic. I can't be bothered to do the conversion to MPG :mark: I figure that's about 35mpg.

My 100L tank takes a little over 100 litres and does up to 400 miles if I drive like a granny and don't tow too much.

If I'm towing (which I do about half the time) and it's windy, town driving or large loads, it's far worse.

In short - I dare not work it out :s

I get 12km/l I dont know how mpg that is but I dont think its much

I'm going for a record. My exhaust has fallen off so i'm getting a 100mile plus lift on a flatbed truck which should make for some great mpg figures. **** you car!

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Originally Posted by Daniel

I'm going for a record. My exhaust has fallen off so i'm getting a 100mile plus lift on a flatbed truck which should make for some great mpg figures. **** you car!

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At Rally GB last year we got recovered from Cardiff to Fife, I wasn't happy, would rather have driven it :(

Daniel get a better car!!! :mad:

I have got on average for the last 3500 miles about 33-34mpg. Although I have my nice fancy mpg computer jobbie I rarely press the button to update it. I know the last time I did was that far ago as I wanted to remind myself I was 4k miles from a service and now I'm only 500 miles away. I just accept I have rubbish fuel economy and just get on with it. :)

A friend of mine recently said to me he got 1000 miles out of his tank and was quite proud of himself. I then asked him how much his tank of fuel cost him and he said £90. Doh, what a moron, thats not good fuel economy, infact it was almost as worse an mpg that I get. He then asked me how much my fuel tank cost and how far I could go but he didn't seem to get it. :s

Doing a lot of motorway driving you can really tell that in the last 6 or so months on average people have really slowed down on the motorways.

Its quite surprising how much you can get out of a gallon if you really try, and it doesn't necessarily involve driving like a granny either.

I run a 2.5 Boxster, and when I bought it, I looked at the official euro fuel consumption figures as that was one of the considerations when buying that car over something like an Audi TT. It's pretty easy to beat the 'official' numbers, so I looked into how the official numbers are arrived at.

It turns out, that there is a standardised procedure for doing an MPG test on each car, and all tests are done on a rolling road, by 'drivers' who are representatives of the manufacturer, and so they have a vested interest in trying to get the best numbers possible. So, you would have thought that the MPG figs produced by the manufacturer would be pretty hard to beat?

Not so!

After having had a think about it, a rolling road really isn't the best way to determine these things, as it can't take account of two major factors.

1, The weight of the vehicle
2, The drag (0r more simply how aerodynamic the vehicle is)

So, a car which is heavy, and with brick like aerodynamics will do comparitively well in the test, but give rubbish figs in the real world, and a car which is fairly light, and aerodynamic will do poorly on the test, but will give better figures on the road.

Now, I couldn't find much out about this rolling road test, but surely it can't be that simple, can it? The way I see it, the testing procedure must be flawed. Does anyone know anything about how the official mpg figs are arrived at?

It wouldn't normally matter much, but these days the car tax is calculated according to the CO2/km (a stupider measure would be hard to think of, what is wrong with plain old MPG which anyone can work out?) so there are financial consequences for car owners if the testing isn't properly accurate, especially if it means paying hundreds of pounds a year more or less.

Anyway, I never get less than 30mpg out of my Porsche, and on one motorway run, at a more or less steady 70-75mpg managed 36mpg. If I were to buy a post 51 reg model, then the road tax would go up from £210/yr, to £380-£400/yr, this would plainly not be fair, as I get better mpg than many, but would be taxed more highly!

Anyway, no point complaining about tax, 'they' will have your money off you whatever you do... Just don't expect me to be voting labour in the next election.

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Originally Posted by Kneeslider

Anyway, I never get less than 30mpg out of my Porsche, and on one motorway run, at a more or less steady 70-75mpg managed 36mpg.

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It's only taken me about seven years to catch you talking bollocks on here mate ;) Although maybe it was a typo! Still - it's amusing nontheless that you bought a 2.5 litre 6 cylinder sportscar and then started chasing economy!

You make a very valid point though about the MPG test. The CO2 measurement is particularly stupid though as whilst EU4 diesels are lower on CO2 and CO emissions, their economy is actually worse:

My last car was a BMW 320d (e46 generation) and day to day driving it returned a genuine 49mpg (measured by me & a GPS unit - not the on board computer which always overread!). If I drove like a Nun on a long motorway journey (i.e. slap cruise control on at 65mph) it would actually return 60mpg!

Replaced this with a BMW 118d (cheaper co car tax due to lower emissions). Now, this is the same engine, detuned from 167hp to 138hp and 'cleaned up' to EU4. In 90,000 miles I have never had a better return than 47.4 mpg from this car. Interestingly it actually has longer gearing which should help economy.

Other cars we run at work have the same issue - I have two diesel Mondeo's on the fleet, neither of which clear 40mpg easily. Yet an old 1.9Tdi Audi clears 55mpg with ease...

I think the emissions equipment (whatever it may be these days) hurts fuel economy in the quest for lower carbon emissions. Yet we're actually burning more fuel, which has to be refined with a larger impact on the environment...

Net conclusion - it's not a green tax at all. It's just a tax.

Kneeslider - Subaru just built a 4 cylinder boxer turbo diesel. What price Porsche to produce a Flat 6 diesel?

Particulate filters absolutely murder fuel economy. My 406 gave 45 mpg over about 500 miles most of which was done with a broken exhaust as well as a lot of time sat still on the m60 and m62 on friday night not moving for a long time as well as an 80 mile thrash (if you can call driving a diesel a thrash) through Snowdonia. Not bad for an old school 1.9 turbo diesel 406. I've chucked some v power diesel in today and am back to nun mode so we'll see what it's really capable of.

I came back from Melbourne and used 35.3L to travel 830km. That's 23.51km/L or 55.301mpg US and 66.418mpg imperial.

Having done the 600 mile round trip for the McRae Stages - I averaged 37.9MPG, that's for a 1998 Seat Ibiza Cupra, not brilliant but not too bad. But still looking for a replacement, not sure though - tempted by a year old Skoda Fabia vRS SE. That is the sensible option, the silly option is for a Renaultsport Twingo 133 Cup - but doesn't have a Trip Computer - which I use all the time when driving. Yeah, sad I know.

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Originally Posted by fizzicist

It's only taken me about seven years to catch you talking bollocks on here mate ;) Although maybe it was a typo! Still - it's amusing nontheless that you bought a 2.5 litre 6 cylinder sportscar and then started chasing economy!

You make a very valid point though about the MPG test. The CO2 measurement is particularly stupid though as whilst EU4 diesels are lower on CO2 and CO emissions, their economy is actually worse:

My last car was a BMW 320d (e46 generation) and day to day driving it returned a genuine 49mpg (measured by me & a GPS unit - not the on board computer which always overread!). If I drove like a Nun on a long motorway journey (i.e. slap cruise control on at 65mph) it would actually return 60mpg!

Replaced this with a BMW 118d (cheaper co car tax due to lower emissions). Now, this is the same engine, detuned from 167hp to 138hp and 'cleaned up' to EU4. In 90,000 miles I have never had a better return than 47.4 mpg from this car. Interestingly it actually has longer gearing which should help economy.

Other cars we run at work have the same issue - I have two diesel Mondeo's on the fleet, neither of which clear 40mpg easily. Yet an old 1.9Tdi Audi clears 55mpg with ease...

I think the emissions equipment (whatever it may be these days) hurts fuel economy in the quest for lower carbon emissions. Yet we're actually burning more fuel, which has to be refined with a larger impact on the environment...

Net conclusion - it's not a green tax at all. It's just a tax.

Kneeslider - Subaru just built a 4 cylinder boxer turbo diesel. What price Porsche to produce a Flat 6 diesel?

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Yup, guilty as charged! Sometimes even I get typo-itis!

So, what is perverse about buying a sporty motor, and then chasing economy? I want my cake, and I want to eat it!

Has anyone taken the trouble to look into exactly how the EU standard emmissions testing is carried out?

If it really is all cobblers, then why aren't there more people who are up in arms about it, or is it just me? Does anyone ever bother? Maybe someone like James May would take an interest in something as anoraky as this?

There are many ways of reducing your carbon footprint, and alas, all of them are dreary! I just have a horrible sense of fatalism about having to pay Gordon £400/yr for the priveledge of driving my next car on his roads. If I end up doing so because of faulty thinking by the government, then I will have no option other than becoming very cross.

Good to see you back btw!

£400 = 4 hours of flying for goodness sake!

Just admit defeat and get a diesel mate! For my next machine I've taken the option of going for the tax effecient economical choice. When it eventually arrives (14 weeks to build a bloody car!) I shall simply drive it to a rolling road and have the engine management reprogrammed and for the princely sum of £350 gain another 45hp and 50nM of torque. But for tax purposes it'll still be a nice "clean" diesel...

Why not invest in a 330Cd - it at least has 6 cylinders.

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Originally Posted by fizzicist

Just admit defeat and get a diesel mate! For my next machine I've taken the option of going for the tax effecient economical choice. When it eventually arrives (14 weeks to build a bloody car!) I shall simply drive it to a rolling road and have the engine management reprogrammed and for the princely sum of £350 gain another 45hp and 50nM of torque. But for tax purposes it'll still be a nice "clean" diesel...

Why not invest in a 330Cd - it at least has 6 cylinders.

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Wouldn't that invalidate your warranty?

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Originally Posted by fizzicist

Just admit defeat and get a diesel mate! For my next machine I've taken the option of going for the tax effecient economical choice. When it eventually arrives (14 weeks to build a bloody car!) I shall simply drive it to a rolling road and have the engine management reprogrammed and for the princely sum of £350 gain another 45hp and 50nM of torque. But for tax purposes it'll still be a nice "clean" diesel...

Why not invest in a 330Cd - it at least has 6 cylinders.

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I do wonder if Diesel is going to be in front in terms of fuel efficiency for much longer. Direct injection and camless engines are going to be very common in a few years. Fiat have their Multiair engines coming out within the next year. They're going to be able to get the same amount of power and BETTER efficiency from a 2 cylinder 900 cc engine as they did from a 1.2l engine. With a very small turbo the power, emissions and fuel efficiency on the same engine will be better than the current 1.4 engine.

I like my 406. It's nice and torquey but it's still not as good to drive as a petrol engined car, I went to pass another car today after a roundabout and pulled out in 2nd with my foot down, revved to just over 4k and no power, so went into 3rd and the same thing and had to change into 4th to finally get past the other car. It's efficient compared to a comparable petrol engine but if direct injection + hydraulic valves give as good fuel efficiency as a diesel with more power and torque over a conventional engine then this will be my first and last oil burner.

Remapping is pretty hard to spot so I doubt he'd have problems with his warranty Andy :)

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Originally Posted by Daniel

...Remapping is pretty hard to spot so I doubt he'd have problems with his warranty Andy :)

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Actually, I thought it's fairly easy, but as long as you remember to re-map to factory settings before you bring the car in for servicing there's no problem ;)

Usually get 42-43mpg in my mum's 1.2 Punto, or if I take it really easily I can get 50, but it takes you hours to get anywhere so I rarely try.

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Originally Posted by fizzicist

Just admit defeat and get a diesel mate!

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The world of commerce and necessity continues to turn about it's axis because people like me refuse to admit defeat when the chips are down. Engines today are good, but not anything like as good as they could be. Diesel is probably the fuel of the future, because of the way that you get more energy from each litre than you can from petrol. Nothing wrong with that, but it's not the whole picture. I like the way that a petrol engine makes it's power, how you can measure it incrementally with each twitch of your right foot, and that is what matters when you are at the edge of grip at the apex.

However, for normal driving, where performance matters for little, then a diesel is going to deliver the performance you need at minimal cost.

Because of this, I very much doubt that anyone is going to make a useful sporting diesel motorcycle. The power delivery simply isn't good enough.

I think kneeslider has hit the nail on the head. My diesel is fine to drive on the way to and from work but on a nice bit of road it's very disappointing. You just don't get the performance per litre (engine size) that you do with petrol. Caroline's car is two years older than mine with a similar sized engine with a turbo. It's got about 120 more bhp than my car and does 0-60 in half the time my car does it in. Sure it does about half the mpg but it gives you a lot more performance. I managed to keep an mr2 behind me on Sunday on the twisty bits over the denbigh moors but as soon as there was a straight bit of road he sailed past. Not that it's a race or anything but in a petrol turbo he wouldn't have got past me unless he wanted to overtake on a blind corner or something.

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Originally Posted by Daniel

I think kneeslider has hit the nail on the head. My diesel is fine to drive on the way to and from work but on a nice bit of road it's very disappointing. You just don't get the performance per litre (engine size) that you do with petrol. Caroline's car is two years older than mine with a similar sized engine with a turbo. It's got about 120 more bhp than my car and does 0-60 in half the time my car does it in. Sure it does about half the mpg but it gives you a lot more performance. I managed to keep an mr2 behind me on Sunday on the twisty bits over the denbigh moors but as soon as there was a straight bit of road he sailed past. Not that it's a race or anything but in a petrol turbo he wouldn't have got past me unless he wanted to overtake on a blind corner or something.

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It does remain to be seen how my diesel performs in that sort of situation. On paper it seems promising, 10bhp more than my petrol engine and almost double the torque, but of course that's not the entire story. Now what I've bought it for is motorway cruising, which is about 95% of my driving these days.

I wonder how it will perform up on the moors when I'm just out for a drive.

Well a turbo diesel will compare favourably when compared to your average normally aspirated petrol engine. But if you compare it to a turbo petrol or a really good normally aspirated engine them there's no comparison.

Not being rude Daniel but in terms of diesel technology the 406 is pretty ancient, even with the HDI engine. Consider that BMW now produce a 2.0turbodiesel with 204bhp and 400Nm of torque and still returns 45-50mpg.

You cannot get that performance & economy from petrol.

Kneeslider is absolutely right in what he says about power delivery for the track and petrol being better for steering a car on the throttle. However on the road, what you want is huge torque and a flat torque curve. Drive a modern performance diesel and you'll quickly discover that on a decent A road you need 4th gear and nothing else - that pulls hard from 30mph to 85mph.

Oh I know. Mine is an old school non-common rail one as well so it's quite primitive. I realise the engines have got better but it's still not the same. No offence taken :p

What's the 0-60 on a 320d? Caroline's ancient Subaru does it in a little over 6 seconds. Now we're talking a car that's 14 years old and an engine which was designed earlier so we're not talking the height of technology. A modern car with a decent engine would be even better in that respect. I realise 0-60 isn't a complete measure of performance but it's a decent measure.

When it comes to fuel consumption there is no comparison as you say. But petrol will get better. Testdrive a mito when they bring out the multiair engines. From what i've heard it's going to narrow the gap in consumption and make the gap in performance even greater.

I've often heard said that when considering petrol vs diesel then it's the 30-60 time that is more indicative. As when out driving you will more often be accelerating from a lower speed rather than stopped

It's also an important consideration when overtaking, where you need to go from around 30mph to over 60mph as quickly as you possbily can.

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Originally Posted by Mark

I've often heard said that when considering petrol vs diesel then it's the 30-60 time that is more indicative. As when out driving you will more often be accelerating from a lower speed rather than stopped

It's also an important consideration when overtaking, where you need to go from around 30mph to over 60mph as quickly as you possbily can.

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True but it depends where you do most of your driving. If you drive mainly in the city then you'll want something that's quick up to 30 and any performance beyong that will be a nice surprise for those times you get on the motorway. My car has a bit of a poke from 30-60 which

Sorry for taking the thread off topic (actually it's Kneeslider's fault but I haven't helped) but I just enjoy good clean discussion. If this were the the F1 forum I'd have been accused of bias against diesel, racism, ethnic cleansing and various other things already :cheese: :mark:

P.S Fizzi, do modern diesels still spew unburnt fuel out the exhaust if you put your foot down in 5th @ 30mph? Nothing gets someone tailgating your more pissed off than a showering of diesel smoke :)

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Originally Posted by Daniel

P.S Fizzi, do modern diesels still spew unburnt fuel out the exhaust if you put your foot down in 5th @ 30mph? Nothing gets someone tailgating your more pissed off than a showering of diesel smoke :)

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From experience in following diesels. The TDi engined ones (usually the VW units) still do give off black smoke. But the PSA TDCi engines (in Peugeot, Citroen, Ford etc) give off a more clear emission, but you can still see it, if you see what I mean.

Did VAG only recently move over to a common rail system on their diesels? Could be a reason for what you've seen. Or not :p

As far as I know VW still don't use common rail?

I wiki'd it and they do on some of their newer engines.

No idea if the other half has a Vag common rail engine, all I know is that I can't drive it for Jack and that's putting it politely. I should really get a diesel as I drive enough miles to warrant the extra expense but I just can't drive them. The other half has a 2.0l 170bhp diesel and it's alot faster than my 2.0l 150bhp petrol but theres just something I don't like about getting all your power in one massive lump. I know I don't rev my engine high enough to use the majority of its power but I'd still rather my petrol than a stinky diesel anyday.