Average Fuel Consumption

mcbutler · Post by **mcbutler** » Sat Apr 21, 2018 4:44 pm

Hi All,

23i - 2009 - 81500 miles

Just finished a 330.8 mile topless drive (roof down, not shirtless). Hull to Plymouth, four rain showers, one very heavy but I stayed dry. Just finished picking the flies out of my teeth and decided to compare actual average MPG with the average the onboard computer gives.

So, I fuelled the car to the brim on Tesco Super unleaded, pretty much on cruise at 70 mph all the way, apart from a few blasts when leaving a service station.

I refuelled immediately upon my return and the Ave MPG reading in the car was 42.2mpg, obviously happy with that.
I recorded the amount of fuel required to fil to the brim = 36.35L, divided this by 4.5 to get gallons = 8.07
Then divided miles covered = 330.8 by gallons = 40.99 mpg (actual).

Pretty accurate by anyones standards I reckon...

eff1guy · Post by **eff1guy** » Sat Apr 21, 2018 6:42 pm

Not bad at all

If you divide by 4.54 which is what a UK gallon equates to, then you'll get nearer your DIS figure at 41.31 mpg or you can creep up to 41.37 mpg if you go the full conversion to 3 decimal places of 4.546

ihadablackdog · Post by **ihadablackdog** » Sat Apr 21, 2018 9:02 pm

Found this the other day....can't be assed with fuelly at the moment.

http://www.mpg-calculator.co.uk

Mr Tidy · Post by **Mr Tidy** » Sat Apr 21, 2018 9:06 pm

Most BMW petrol 6s seem to be surprisingly economical in my experience.

I've done 4,400 miles since my Z4C had a new battery and the OBC is showing 33.6 mpg at the moment which seems pretty good to me.

Although I don't commute, I do like to chase the red line when I get the chance.

But 40+ mpg is impressive (I just don't have the will-power).

Vonlipvig · Post by **Vonlipvig** » Sat Apr 21, 2018 9:38 pm

Sounds good to me

I did Plymouth to Surrey and back this week, top down one way, big diversions each way and was not hanging around. Got 36mpg from mine (calculated based on the fuel receipts as it is going on expenses)

buzyg · Post by **buzyg** » Sat Apr 21, 2018 10:12 pm

41mpg. No not never no more am I ever going to see that.

markalp · Post by **markalp** » Sat Apr 21, 2018 10:58 pm

Well the MPG from the computer in my Alpina is 12.4 however that is in london traffic, with heavy accelerating and braking on a regular basis (those gaps in the traffic dont dome along very often in central london)

del_tl1000r · Post by **del_tl1000r** » Sun Apr 22, 2018 7:10 am

My car is a daily driver. Commute 70miles a day, mixture of motorway, dual carriageway and town driving. Average 34mpg.

mcbutler · Post by **mcbutler** » Sun Apr 22, 2018 8:32 am

Mr Tidy wrote: ↑Sat Apr 21, 2018 9:06 pm Most BMW petrol 6s seem to be surprisingly economical in my experience.

I've done 4,400 miles since my Z4C had a new battery and the OBC is showing 33.6 mpg at the moment which seems pretty good to me.

Although I don't commute, I do like to chase the red line when I get the chance.

But 40+ mpg is impressive (I just don't have the will-power).

Will power was the hardest thing, the sun brought out the supercars including two of those insane Mercedes AMG GT Coupes. They sound like a spitfire, incredible... Very tempting not too chase it just to hear it go.......

Busterboo · Post by **Busterboo** » Sun Apr 22, 2018 9:23 am

mcbutler wrote: ↑Sun Apr 22, 2018 8:32 am ... the sun brought out the supercars including two of those insane Mercedes AMG GT Coupes. They sound like a spitfire ...

Messerschmitt, actually.

Z4Rick · Post by **Z4Rick** » Sun Apr 22, 2018 2:59 pm

For comparison, I just finished a 2157 mile trip in my 35i, and showed 28.9 avg.mpg, and 63.6 avg. mph (all US numbers). I am very pleased with that. I have a very spirited driving style, and this vehicle gets TWICE the mileage of BOTH my 4X4 SUVs, (almost 3x the heavily modified FJ Cruiser!)

mcbutler · Post by **mcbutler** » Sun Apr 22, 2018 5:28 pm

Z4Rick wrote: ↑Sun Apr 22, 2018 2:59 pm For comparison, I just finished a 2157 mile trip in my 35i, and showed 28.9 avg.mpg, and 63.6 avg. mph (all US numbers). I am very pleased with that. I have a very spirited driving style, and this vehicle gets TWICE the mileage of BOTH my 4X4 SUVs, (almost 3x the heavily modified FJ Cruiser!)

A US Gallon is = 1.2 UK gallons I believe?

Nick9one1 · Post by **Nick9one1** » Mon Apr 23, 2018 3:08 pm

I wish!

: 20171224_142856_preview.jpeg (143.86 KiB) Viewed 1186 times

Gaffa22 · Post by **Gaffa22** » Mon Apr 23, 2018 3:38 pm

mcbutler wrote: ↑Sun Apr 22, 2018 5:28 pm A US Gallon is = 1.2 UK gallons I believe?

yes it is 1.2009 so gives 34.7 MPG which is quite impressive with an average speed of 63.6

Z4Rick · Post by **Z4Rick** » Wed Apr 25, 2018 2:54 pm

In fairness, virtually all of the miles were on super- highways with speeds from 65 mph to 90 mph... Baltimore to Miami and back. A good deal was done on cruise control, but some notably empty sections were run in triple digits...... I think this is the best mileage I have ever gotten......in ANY car.

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