Big engines are more economical?

[Palfrem]

Smallest cars 'worse for fuel economy' - Telegraph

Well, well, well.

What a revelation. Even more I guess when passengers, etc. are factored in.

So does that mean the CO2 figures will be wrong as well?

 

[moonloops]

Performance models with larger engines delivered worse fuel economy, but the test results were closer to manufacturers’ estimates.

..?

 

[Giantvanman]

That makes for interesting reading. Would like to see a larger study, government U-turn, and minimum legal engine capacity of 3 litres.

 

[blue gnome123]

Well ... it depends.... on where you are driving...and how you are driving. Small engine in city driving is always going to be good and bigger engines / long ratios are best on faster roads/motorways.

..... goes to look at V8's.....

 

[boxbrownie]

But it is the Telegraph, the same paper that last week answered a query on Lexus RX battery pack replacement cost, they stated to a prospective buyer it would be approx £1200 fitted......when actually it is more like >£2500

Sure hope he didn't buy the RX with a duff pack on their say so!

 

[grober]

I reckon one of the major differences is in engine heat up time- bigger engine= bigger block of metal/mass of water to heat up. That's where little engines score. Petrols at least. Diesels take longer anyway being more thermally efficient .

 

[IanMSpencer]

Report doesn't tell us anything we didn't already know: underpowered engine labouring in an un-aerodynamic box is inefficient, a very large car is inefficient because of the weight it is lugging around and may not actually get into its efficient operating output either.

The report also amazingly lumps together 1.0-2.0l engines, where that is where it becomes interesting, especially as there is 90s technology in there and up to date technology.

Does it answer the the question: how does a 1.4 bi-turbo petrol (VAG style) 180hp compare with a large traditional block, diesel or petrol?

 

[gIzzE]

You have to buy a car to do the driving you do.

It is that simple.

 

[MancMike]

But it is the Telegraph

All the papers are writing articles based on this research. The DM has it too.

 

[grober]

To certain extent you have to look a the type of journey the average motorist takes on a daily basis. Many journeys are relatively short, Tesco's shopping, the school run, commute to work or the station. Even the motorway muncher doesn't live on the approach ramp! Chances are they will have to negotiate a bit of built up area before arriving at their natural habitat. The fast lane. In the real world most of us inhabit there is where the car that warms up fastest wins the fuel consumption war?
The latest cars have lots of developments to aid this. The ubiquitous OM651 2.2 litre diesel has a variable output water pump , a variable oil circuit, an EGR cooler, direct injection and switchable piston cooling all to help with rapid engine heat up. New petrols are the same.
However these clever devices would tend to multiply the chances of engine component failure so maybe for the owner big old and simpler is a better long term proposition even if they do use a bit more fuel?

 

[boxbrownie]

All the papers are writing articles based on this research. The DM has it too.

Daily Mirror.....great for chips.

 

[Charles Morgan]

Watching journalists misunderstand anything technical was one of the joys of my life in finance (if they could do it they wouldn't be journalists) and all they will do is top and tail a press release. What the headline should have said is that small cars underachieve their official mpg figures by more than larger cars. Not difficult really.

 

[Sp!ke]

I am prepared to throw down the gauntlet and challenge any car that's greater than 2L in capacity to better the mpg of my 800cc CDI.

I do agree with the article to some extent though. Small turbo charged petrol engines get nothing like the official mpg claims ever.

Diesels on the other hand can often be coaxed into being pretty close.

 

[Deane x]

Is my V8 better on fuel than my 1.6 d ford b-max .....NO ...but is it more fun. Oh yes that's all that matters :bannana:

 

[automaniaman]

I think I might loose this challenge...

 

[MancMike]

Daily Mirror.....great for chips.

I meant daily mail.

 

[Deleted member 37751]

I am prepared to throw down the gauntlet and challenge any car that's greater than 2L in capacity to better the mpg of my 800cc CDI.

I'll take up the challenge, but the test for the mpg must be both cars sat at 100mph.

 

[st13phil]

Amongst the more technically savvy, it's well appreciated that motor manufacturers employ a number of artificial devices to improve the fuel economy of their vehicles in the standard EU test regime. The focus on CO2 emissions-based taxation is another driver for this. As such it's no surprise that when driven in real world conditions, the achieved fuel consumption is often at significant variance with the "standard test" figures.

I suspect that manufacturers worry less about demonstrating good economy in the standard EU testing regime for larger engined high performance vehicles, and therefore the real world fuel consumption is probably closer to the published numbers. For example, in everyday use my E63 achieves roughly 85% of the statutory combined figure which is the closest I've ever seen with any of the cars I've owned.

 

[Sp!ke]

I'll take up the challenge, but the test for the mpg must be both cars sat at 100mph.

I cant do 100mph.

 

[Deleted member 37751]

I cant do 100mph.

I win!