ALF
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Official "combined" mpg's - officially useless?For some time drivers of modern turbodiesels have been questioning the validity of official combined mpg figures, now the disease seems to have spread to most new cars - especially (but not only) turbos.
I bought "Car" magazine the other day (as I needed cashback and couldn't find a cash machine!) and it has all sorts of long term testers in the back. With the exception of a handful of cars, notable the IS-F (which seems economical for that sort of car) the cars were all way, way underperforming compared to the official combines mpg. There was a day when, because the official test is urban-based, you could expect to easily better it in normal use (as I have with the GTA). Now, it seems if you are with 25% of it in normal use, that's a bonus. The allegedly green cars seem the worse offenders, and the rapid Twingo was shocking at about the same as I'm getting from the GTA on long runs! What's the point of a weeny car with a shitty little buzzbox of an engine if you can't feel smug at the pumps?
On another note Car magazine officially has the weirdest lack of connection between star ratings and comments on various cars, and an even wirder stance on Alfas than Autocar. If the 159 and Brera are not advances over the 156 and GT, for 99% of drivers, then I'm the Pope.
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Blarno
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Official combined book figure for my Clio is 34 mpg.
Last month's average: 34.3mpg.
Light car + torquey engine = smugness!
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Guitar Zero
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If you look at the speeds achieved during the combined tests, I don't think the car goes over 75 mph.
So, to replicate the official figures, you have to drive very slowly whilst treating the accelerator like the detenator on a thermo nuclear doomsday device.
Just assume you were in charge of designing a new economy test - how on earth would you replicate a typical urban drive ?.
I'd just take constant fuel economy readings every 10 mph starting at 20 mph in the highest gear practical.
I suspect the readings at 40, 50, 60, 70 and 80 would prove most useful.
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ALF
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| Guitar Zero wrote: |
Just assume you were in charge of designing a new economy test - how on earth would you replicate a typical urban drive ?
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I wouldn't want to - it's just townies making the rules  I can't be alone in hardly ever crawling along in traffic for any length of time, plenty of other drivers must be in the same situation - especially across much of the rest of Europe where "urban" driving must make up a really small % of the average car's use.
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Guitar Zero
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Exactly - it's hugely different for every driver so doing an urban test is a waste of time.
My suggestion sounds top - let's tell the Guvverment fukks to use it.
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TimR
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Dunno if you noticed this ALF but at the back section, where they've got the manufacturer named and it's equivalent pop band  they also supply last year's sales figures.
Re - the Alfas do you really think the Brera and 159 are an acceptable improvement over the GT and 156 given the 6 or 7 years between them?
If you take the V6 versions then by all accounts the engine alone is a disappointment and added to the extra weight makes them a poorer car.
I know I'd much rather have a GT than a Brera.
At least they're telling us what the cars are worth at the end of the test, although last month they kind of glossed over that in the text for Georg Kacher's Audi, perhaps because he'd had it painted beige and fired a shitload of other extras at it - just like their Audi TT TDI actually (28% loss in actual cost over 6 months and 8k miles  )
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DaveGibson
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The combined figure on the IS250 is 28.8mpg and that's about what I get from mine, even though it does far too many short trips. If I were still doing the sort of mileage I did when at work, I'd be expecting about 35mpg.
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gonnabuildabuggy
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Welcome your holiness - is the next car going to have a big glass dome?
I suggest that car's are tuned to max the figures on the tests, in anything else they will fall short - but then who doesn't work hard to hit their targets at the cost of other factors sometimes.
328 does 28mpg sitting a silly speeds on the motorway, urban it plummets.
I loved the M3 vs Prius test Top Gear did which showed the Prius to be less economical than the M3 when driven like one.
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Gurney
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I was told that some engine mgt systems are so clever that they can detect the Govt economy test and artificially/temporarily go into a mode naff for road use but excellent for bamboozling co2/mpg figures.
It's a conspiracy I tell you 
Don't much care I was doing precisely 11.2mpg when I mullered a desperately accelerating Clio 182 as we both joined the M67 very late last night. He didn't look pleased.
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ALF
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Here are the CAR figures, since I'm at home. Actual achieved on long term test first, claimed in brackets. These cars are doing serious mileage as well, not just a few miles of B-road fun:
A5 3.0TDi - 29.3 (42.8)
Kuga TDCi - 34.9 (44.1)
Toyota iQ - 47.1 (65.7)
Toyota Avensis diesel - 38.8 (50.4)
Fiesta (model - some green shyte) - 56.3 (76.3)
Jag XF (assuming 2.7D) - 29.6 (37.6)
Audi TT (diesel again - yawwwwwwwwwn rattle rattle) - 42.5 (53.3)
Golf 6 TDi - 41.9 (52.3)
Renaultsport Twingo - 30.1 (40.4)
Lexus IS-F - 24.0 (24.8)
Bentley GT - 16.8 (17.0)
Pretty shocking overall. Generally the bigger NA petrol stuff is doing better, and the small engines worse.
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Gurney
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Ah, that makes me feel better 
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Eff One
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That Twingo figure is very poor, and unfortunately replicates Autocar's road test figures. I was quite tempted by the pics and reports, but part of the appeal is fun on a budget. My Fiat Barchetta and MX-5 - both heavier, more powerful and poorer aerodynamically - both managed 32-35mpg with ease.
Mind you, I'm no leadfooted road tester - my GTA never dipped below 26mpg over a tankful and was normally in the low 27s.
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Pkh72
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Now my commute is mostly stop/start on Derbys outer ring road the average fuel consumption on the ST has fallen to about 25/26.
A nice run up to York and back last weekend saw it rise to the low 30's.
The old girl's not that keen on the old stop/start stuff, much like the owner really.
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ALF
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If I thought I could get low 30's from an ST I'd add it to the list - I thought the 5-pot was not that economical?
Looking at what I actually get from 60 litres, the GTA's gauge is probably a couple of mpg optimistic - I'd need to be doing 400 miles between fill-ups to genuinely reach 30mpg, and it's rare I've managed that. The Audi makes 500 between fill-ups in similarly good conditions (38mpg) and tends to manage 450 even when driven quite hard (34mpg) - good for a car that is not small and far from slow...
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Dr. Hfuhruhurr
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Filled up yesterday: 55.67 litres after 244 miles, which makes just a whisker under 20 mpg. Not great, until you consider that most of that was autobahn. What was definitely not great was the price: €1,48 per litre!
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gonnabuildabuggy
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| Pkh72 wrote: | | A nice run up to York and back last weekend saw it rise to the low 30's. |
What speeds a nice run?
From what I've seen I'm doing well - solid average of 28mpg (on OBC so perhaps needs a check) on my commute based on tanking (and I mean tanking) up and down the M'way for 50 miles, 7 mile A Road at strady 60 due to cameras and 3 mile B road blast.
And to point out this is a 130K mile engine.
I'd be hacked off to have an Avensis diesel and only be getting 38.8. 
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Pkh72
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| gonnabuildabuggy wrote: | | Pkh72 wrote: | | A nice run up to York and back last weekend saw it rise to the low 30's. |
What speeds a nice run?:grin:
From what I've seen I'm doing well - solid average of 28mpg (on OBC so perhaps needs a check) on my commute based on tanking (and I mean tanking) up and down the M'way for 50 miles, 7 mile A Road at strady 60 due to cameras and 3 mile B road blast.
And to point out this is a 130K mile engine.
I'd be hacked off to have an Avensis diesel and only be getting 38.8. |
It took 90 minutes to do 99 miles coming back home. I'm too thick to work out an average speed.
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"him"
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66 mph
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Pkh72
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| ALF wrote: | If I thought I could get low 30's from an ST I'd add it to the list - I thought the 5-pot was not that economical?
Looking at what I actually get from 60 litres, the GTA's gauge is probably a couple of mpg optimistic - I'd need to be doing 400 miles between fill-ups to genuinely reach 30mpg, and it's rare I've managed that. The Audi makes 500 between fill-ups in similarly good conditions (38mpg) and tends to manage 450 even when driven quite hard (34mpg) - good for a car that is not small and far from slow... |
It depends very much on the type of journey you have to do and your style of driving.
I tend to anticipate reasonably okay so on a day to day basis i keep things flowing, which i think helps.
I do overtake stuff and explore the upper reaches of the rev range where appropriate but i don't drive round like my arse is on fire all the time.
That may be why my mpg doesn't sit in the low 20's like some do.
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TimR
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| Gurney wrote: |
Don't much care I was doing precisely 11.2mpg when I mullered a desperately accelerating Clio 182 as we both joined the M67 very late last night. He didn't look pleased. |
I bet he looked a bit happier when he managed to pass the next petrol station though
From the CAR figures it's not just the small petrols that struggle but all the diesels too.
Maybe they'll get a Pious soon and we can see how that compares.
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Gurney
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| TimR wrote: | | Gurney wrote: |
Don't much care I was doing precisely 11.2mpg when I mullered a desperately accelerating Clio 182 as we both joined the M67 very late last night. He didn't look pleased. |
I bet he looked a bit happier when he managed to pass the next petrol station though
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I tailed him all the way from Penistone over the Woodhead, he braked so often I was surprised he had any pads left by the time he got to the end of the M67. He was unnecessary ballast in a fine car.
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Dr. Hfuhruhurr
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| Gurney wrote: | | I tailed him all the way from Penistone over the Woodhead ... |
Don't you just hate it when that happens. Great road, but if you get stuck behind something ...
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Gurney
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| Dr. Hfuhruhurr wrote: | | Gurney wrote: | | I tailed him all the way from Penistone over the Woodhead ... |
Don't you just hate it when that happens. Great road, but if you get stuck behind something ... |
He was at least faster than the 20 odd cars and Shell petrol tanker on the outward journey. 25mph virtually all the way, oh the agony.... 
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Dr. Hfuhruhurr
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I once managed to get past a Shell tanker on what must have been the only overtaking spot. Hence clear run all the way down ... bliss!
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Martin
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It's possible if you drive like a granny. I went with the flow on the A420 to Oxford earlier in the week and was trying to be particularly smooth to see what I could get. The average for the whole journey of 40 miles at 40-50 on single carraige way and 70 on dual carraige way was 58.2 (probably a real 55ish)
Some quick driving down the M5 and A417/419 gave me 36.2mpg on the 60 miles from filling up which is definately my worst so far. That's back up to 44mpg now, after a couple of trips to MK.
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TimR
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The difference between real and official figures is highlighted again in the latest issue with the 'green' test of the Honda Insight, Golf, Focus and Megane.
The worst performer is the Honda with an actual of 42.7 against claimed 61.4.
The Focus does 47.7 against 65.7.
The Megane was 44.5 against 55.4.
The Golf was 49.8 against 57.6.
The Focus was an Eco version with a 1.6 diesel and 5 gears.
I wonder what difference it would've made trying a bigger engined 6 speed one (if they still do a 1.8 or 2.0 diesel).
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Bryan M
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I think it also depends on the age of the cars especially with the Diesels - when new mine would struggle to make 42mpg av but with 30k on the clock it is easy to average over 53mpg and indeed 70mpg as I was showing everyone on Saturday!!!!
do they run cars in before they do the economy tests?
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cbeaks1
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My last car was a 1.6 TDCi 5 speed C-Max and its average (indicated admittedly but I think it was very close) was over 55mpg. it wasn't difficult to do over 60mpg when trying.
My current Mondeo is still at 54mpg after 1600 miles.
Its all a bit pointless really - how could you hope to hit a figure made in controlled conditions and the parameters of which you can't replicate. Even doing 75mph instead of 70mph on a motorway makes a big difference.
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TimR
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I noticed my diesel Stilo took a good 10k miles to give it''s best performance/economy.
I think magazine tests are usually done on fairly low mileage cars - often under 1k.
I forgot to mention before how irritated I was that Ben Oliver went to Hungary to test the new Lexus RX450 hybrid (the SUV one) and there was no mention of actual economy.
Surely that's the whole point of the hybrid version?
I bet there's no way it gets close to 44.8mpg.
Actually perhaps mag tests should start telling us the real emissions.
If the 4x4 hybrid is supposed to do 44.8 mpg and 148g/km but really does,say, 25mpg then what is the actual g/km?
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Dr. Hfuhruhurr
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| TimR wrote: | | If the 4x4 hybrid is supposed to do 44.8 mpg and 148g/km but really does,say, 25mpg then what is the actual g/km? |
265.2 would be my guess, since I presume it's more or less proportional to mpg.
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TimR
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I didn't actually mean for someone to work it out but thanks anyway
Have any of the mags done a proper test of a hybrid against a sensible diesel yet?
The only tests I know of are the Top Gear Pious v M3 and EVO's test of a Pious against a Panda 100HP.
Neither is particularly 'real world'.
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