Great MPG or am I crazy?

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s13b
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Post Fri Sep 21, 2012 5:43 pm

So bought my E30 yesterday from Peterborough, its an '88 plate 325i on about 120xxx miles. Been sat a while but actually in very good condition considering age etc (virtually no rust!).
Its completely standard, running on comedy tractor size tyres.

Anyhow, it had quarter of a tank when I got it. I put £30 before I left Peterborough which was about 18.xx litres (or ~4 gallons). I then drove 160 miles (Mostly motorway and private dual carriage way) down to Worthing, then another 20 odd miles to near Portsmouth. I am now showing just below quarter of a tank!!!
Thats about 180 miles of 70 - 80 mph, including several bouts of (very) spirited driving.
So thats over 40mpg unless my maths is wrong, was expecting about 25mpg at best. Hope it continues.
suchy
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Post Fri Sep 21, 2012 5:50 pm

The only way an M20 will break 40mpg is downhill with the engine off!!
Fill the tank, reset the mileage and then do the maths when you refill again, won't be close to 40 :thumb:
snakebrain
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Post Fri Sep 21, 2012 5:51 pm

Your fuel tank sensor is probably just wonky. :D
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HJG-E30
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Post Fri Sep 21, 2012 5:51 pm

Sorry to dishearten you here, but sadly 40 MPG is impossible in a 325i !! I would be checking for correct operation of the fuel gauge . . .
Andy325i
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Post Fri Sep 21, 2012 5:55 pm

suchy wrote: Fill the tank, reset the mileage and then do the maths when you refill again, won't be close to 40 :thumb:
This!

Enjoy your new toy :D
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Brianmoooore
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Post Fri Sep 21, 2012 6:26 pm

The only way you'll see 40 MPG on a M20 325 (in cost equivalent terms) is to run it on LPG.
Jim320i
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Post Fri Sep 21, 2012 6:36 pm

I had 39.9mpg in the auto 320i last year coming back fro
Beaulieu. Filled up before we left. Filled up when we got back. Got the mileage between both petrol stations and that was the result.
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Gavla
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Post Sat Sep 22, 2012 12:55 am

Nothing wrong with a bit of wishful thinking? :D
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andyp
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Post Sat Sep 22, 2012 1:39 pm

i would of said no way, but i had 36mpg going to the ring, a tank from here got me to the hotel
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s13b
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Post Sat Sep 22, 2012 5:46 pm

hahaha yeh I can understand the skepticism. This is my 2nd e30 325, hence expecting around 25mpg. Based solely on the maths however I did ~180 miles on 4 gallons of fuel (not based on speedo or fuel gauge). I will try running it to empty and see what I get on a tank!
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batleyrhino
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Post Sat Sep 22, 2012 6:58 pm

At 25MPG or so, should you get about 350 miles from a full tank on a 325? Have I got the sums right?
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Brianmoooore
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Post Sat Sep 22, 2012 9:48 pm

BMW's figure for a 320i saloon at a constant 56MPH is 42.2MPG, so the figure you claim isn't totally ridiculous for a well maintained and serviced E30.