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MPG
Posted: Thu Apr 14, 2011 6:55 am
by RogerRust
Why do we still quote Miles per gallon.
Now all fuel is in litres I find myself doing mental arithmetic in the mornings. I know the continental version is litres/100Km
That's to complex
how about MPL we could all aim for the magic 10 = 45.4 MPG
It would make my early morning maths easier!
Re: MPG
Posted: Thu Apr 14, 2011 8:44 am
by chickenjohn
Yes, all you have to do is divide the litres by 4.54.
The imperial measurement system is part of our culture and owning a classic car is part of preserving our British culture under the onslaught of EU rules and regs. So be Imperial and be proud!
Keep the miles, gallons and inches and pounds alive!
Re: MPG
Posted: Thu Apr 14, 2011 10:35 am
by morrisminorbzh
chickenjohn wrote:Yes, all you have to do is divide the litres by 4.54.
The imperial measurement system is part of our culture and owning a classic car is part of preserving our British culture under the onslaught of EU rules and regs. So be Imperial and be proud!
Keep the miles, gallons and inches and pounds alive!
Agree with you no end - You must keep the miles, gallons and pounds alive !!! Look at what EU onslaughts have done to
real French cheese etc ! I know some older French people who still ask for goods in "livres" (which is around 500g) others still ask "what's that in ancien Francs ??"

Re: MPG
Posted: Thu Apr 14, 2011 1:05 pm
by win
mine only runs on gallons, I am having none of that litres rubbish.
But I do measure in thous, millimeters, feet and CWT, and manage to drink a half litre can,
no wonder anyone in my vicinity looks bewildered when I speak.
Re: MPG
Posted: Thu Apr 14, 2011 6:48 pm
by bmcecosse
Imperial all the way! Just confirmed my Fusion did 61 mpg on the last brim to brim fill - confirming exactly the 'computer' readout.

Re: MPG
Posted: Fri Apr 15, 2011 7:20 am
by RogerRust
Oh good! I enjoyed that little wind up.
What promoted it was buying a sheet of wood at the weekend on measuring it I realised it was 4ft x 2400mm!!!
Re: MPG
Posted: Mon Apr 18, 2011 1:01 am
by Roni
Here, in NZ, you buy petrol by the litre, measure distance by the kilometer yet still quote fuel economy in MPG, at least in the classic car world. L/100km never really seemed to catch on. It doesn't seem right when talking of an older car. It does mean keeping a calculator in the glovebox (why still use that term?) though.
Re: MPG
Posted: Mon Apr 18, 2011 10:40 am
by irmscher
gallons ,feet and inches ,pounds and ounces im,e not changing to foreiegn policy

Re: MPG
Posted: Mon Apr 18, 2011 12:27 pm
by rayofleamington
l/100km works really well if your milometer is in km (e.g. in the rest of Europe) and is a nice measurement to use if you're on a long journey (e.g. I need to go 250km , that'll use about ##litres of fuel..). Having driven a lot across Europe it is an easy measurement to get your head around.
Miles per litre doesn't really show the difference between driving a bit more calm etc.. as it will only change by a little bit after the decimal point. What I recon we should start using in the UK is litres/100 miles!
Whichever way you find the fuel economy you'll need a calculator anyway.
As for metrinch madness - think about tyres. The diameter is in inches, the width in mm and the profile is in percentage

Re: MPG
Posted: Mon Apr 18, 2011 1:30 pm
by win
yes and the cost is in LBS
Re: MPG
Posted: Mon Apr 18, 2011 3:20 pm
by katy
L/100km X 2.825 = MPG (imperial gallons, not US gallons)
Re: MPG
Posted: Mon Apr 18, 2011 11:45 pm
by Neil MG
katy wrote:L/100km X 2.825 = MPG (imperial gallons, not US gallons)
That can't be right....
Re: MPG
Posted: Tue Apr 19, 2011 9:24 am
by MarkyB
2825 comes into it somewhere if this site is to be believed;
http://mpg.webix.co.uk/
My maths aren't good enough to work out how exactly.

Re: MPG
Posted: Tue Apr 19, 2011 11:18 am
by rayofleamington
l/100km can't be converted to mpg by multiplying as they are inverse parameters (one gets smaller the other gets bigger)
I'm going to go and think...
Re: MPG
Posted: Tue Apr 19, 2011 11:21 am
by rayofleamington
simples
285 / (l/100km) = mpg
(I got 284.4 when I used a calculator with the conversion factors to 'not many' decimal places)
Re: MPG
Posted: Tue Apr 19, 2011 2:19 pm
by Neil MG
rayofleamington wrote:simples
285 / (l/100km) = mpg
(I got 284.4 when I used a calculator with the conversion factors to 'not many' decimal places)
That seems right!

Re: MPG
Posted: Tue Apr 19, 2011 3:15 pm
by katy
My mistake, km per litre X 2.825 = MPG.
Is l/100 km the same as litres per 100km?
Re: MPG
Posted: Tue Apr 19, 2011 3:27 pm
by rayofleamington
Is l/100 km the same as litres per 100km?
yes
rather like mpg = miles / gallons (the / is keyboard shorthand for the divided by symbol e.g ΒΌ)
Re: MPG
Posted: Tue Apr 19, 2011 8:25 pm
by MarkyB
Per 100 kilometres feels like a bit of a bodge to give a sensible number.
I feel like an old dog unwilling to learn new tricks, MPG I understand, I'd have to convert to that to be able to say that's not bad, or that's terrible.
Re: MPG
Posted: Wed Apr 20, 2011 10:05 am
by rayofleamington
Bodge - yes probably but it gives good numbers and it does help you know how much fuel a journey will take.
Range:
5 is excellent 8 is average. Over 10 is poor.
Over 15 is only for those who can afford it!