True MPG - online database?

Tom_ed1987

Tom_ed1987

Tom_ed1987

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We all know manufacturer quoted eonomy figures are 'optimistic' to put it mildly. Does anyone know of a website/service where you can view true/real world MPG figures?
I'm really just looking for a massive list of cars against the economy they actually achieve at a constant X mph. (where X hopefully = 80ish MPH)

https://spreadsheets.google.com/spr...AQiOkdEV6WUVjRDhaUF8tclEydHpyblFTVFE&hl=en_GB

I've found the above courtesy of whatmpg.co.uk, but there is no detail of usage patterns so the data is pretty meaningless.

http://www.fueleconomy.gov

Figures on the above are courtesy of the EPA in the US, and seem a bit more realistic although the 'highway' portion of the test looks to cover a fairly varied speed up to a maximum of 60mph.
 
I imagine they are just running some simple calculation based on some factors such as whether the car has Start/Stop etc.

That spreadsheet is completely pointless.

The ultimate problem with the fuel economy tests is that they have to account for everything that goes through the test. This means that a car that does 0-60 in 45 seconds is getting a bit of a move on to meet the acceleration standards, yet an 8-speed 400 HP car is accelerating so slowly it doesn't break 1300 RPM. The reality is that pretty much nobody drives two different cars in the same way, and as such any kind of fair real-world figure is impossible.
 
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toxicredcat said:
Very dependant on each persons driving style
Click to expand...
Exactly this, driving style and traffic dominate fuel Economy.

After 13,000 miles I've averaged 45 MPG, which is only 4 MPG off the combined figure from BMW.
Yet, other drivers in the same car & engine complain of poor fuel economy, only getting mid to high 30's.
 
remember many things count towards your mpg things like constantly carrying 3 or 4 adult passengers, whether your cars serviced regularly ( glow plugs spark plugs etc ) tyre wear and pressure, how heavy a right foot you have all contribute to your maximum mpg.

also worth noting generally t he max mpg a car manufacturer gives is at a set mph over a set amount of miles. how many people would drive 500 miles at almost exactly 56mph???
 
vicky953 said:
remember many things count towards your mpg things like constantly carrying 3 or 4 adult passengers, whether your cars serviced regularly ( glow plugs spark plugs etc ) tyre wear and pressure, how heavy a right foot you have all contribute to your maximum mpg.

also worth noting generally t he max mpg a car manufacturer gives is at a set mph over a set amount of miles. how many people would drive 500 miles at almost exactly 56mph???
Click to expand...

Take a look at this for some info about car official MPG
Why the EC figures do not represent true MPG
The prescribed EC test is a lab test carried out to simulate a mix of different types of driving and arrive at ‘combined’ CO2 emission and fuel consumption figures.

Because vehicle taxation in Europe is now based on CO2 emissions, manufacturers naturally optimise their engines to achieve the lowest possible CO2 in the tests - this skews the true MPG.

This gives a correspondingly low fuel consumption figure. Unfortunately the relevant EC Directives prescribe that this figure and only this figure can be publicised by manufacturers, even though it is unlikely to be achieved by the average driver in real life conditions.
Imperial urban fuel consumption (mpg) (cold)

The urban test cycle is carried out in a laboratory at an ambient temperature of twenty degrees celsius to thirty degrees celsius on a rolling road from a cold start, ie the engine has not run for several hours. The cycle consists of a series of accelerations, steady speeds, decelerations and idling. Maximum speed is 31 mph (50 km/h), average speed 12 mph (19 km/h) and the distance covered is 2.5 miles (4 km).
Imperial extra-urban fuel consumption (mpg)

The extra-urban cycle is conducted immediately following the urban cycle and consists roughly half steady speed driving and the remainder accelerations, decelerations and some idling. Maximum speed is 75 mph (120 km/h), average speed is 39 mph (63 km/h) and the distance covered is 4.3 miles (7 km).
Imperial combined fuel consumption (mpg)

The combined figure presented is for the urban and the extra-urban cycle together. It is therefore an average of the two other parts of the fuel consumption test, urban and extra-urban cycles, weighted by the distance covered in each part.
Click to expand...
 
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