What do you get?? "MPG.."

Discussion in 'American RV's' started by old-mo, Sep 11, 2009.

  1. old-mo

    old-mo Funster Extra Special Life Member

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    On our first proper trip,, we were according to the computer thingy getting a return of lowest 9.8 MPG to 13.7 on the flat-ish at an average speed of 55 - 65 MPH. and that was running on LPG..

    So I suppose that equates (LPG Costs) to approx 18 - 19 / 24 - 28 MPG..

    That is pretty well loaded full water tank/petrol tank,, enough food and wine to feed an army and all the usual rubbish one carry`s and a 4 wheel trailer and car..

    8.1 ltre Vortec,, returned about 280 miles to a full tank of LPG..

    Does this sound about right ?
     
  2. Lampie

    Lampie Read Only Funster

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    Sounds to me given the size of the engine 9 - 13 MPG is fairly good. Our 6.8 V10 C Class I think gives us around 12 MPG.

    Regards

    Lampie
     
  3. savantuk

    savantuk Read Only Funster

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    Our last trip - Ducato 2.3D - returned 28 mpg, over a trip of 1500 miles, thats an equal mix of motorways, good A roads, and not so good A roads in North Wales. I'm quite happy with that.
     
  4. Geo

    Geo Trader - Funster

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    Sorry Mo those numbers do not add up to me
     
  5. old-mo

    old-mo Funster Extra Special Life Member

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    How do you mean Geo ??

    Going up hills/inclines the reading was 9.8 and on the flat at a constant 55 to 65 MPH it was showing 13.7 ..

    on LPG ?

    That is why I asked the question. does that sound about right..
     
  6. simsy56

    simsy56 Funster

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    Hi,old mo,

    When you say, 'on the computer thingy', is that the one onboard? And if so, just a question, is it the consumption of US gallons or Imperial gallons? l have been meaning to ask someone for a while now.
    Craig.
     
  7. old-mo

    old-mo Funster Extra Special Life Member

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    Hi,, Yes it is the built in comp thingy.. :thumb:

    Now you have confused me,, cos US miles are different to ours :Doh:

    So the be all is I dont know what I am getting. :cry:

    I was hoping "Geo" would come back with some sort of explanation,, as I think he is an old hand at this American RV stuff..

    spose really I am just after what to expect MPH on a brute like mine.. :BigGrin:
     
  8. Geo

    Geo Trader - Funster

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    Your using your computer to calculate MPG,I dont supose its calibrated to work out LPG therefore in my opinion the calculation may be wrong
    Usualy an LPG conversion on that engine would at best return 18 -20 when worked out correctly
    I sincerley hope im Wrong:RollEyes:
    Olley and others who have spent many an hour and many a formula to work it out more exact may post in responce :thumb:
    Geo
     
  9. scotjimland

    scotjimland Funster Life Member

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    Hi Mo

    as far as I'm aware, a US mile is the same as a UK mile..
    but 1.0 US Gal = 0.8327 Imperial Gal. or 1 Imperial Gal = 1.201 US Gal

    So, if your computer is calibrated for US gal , then your MPG Imperial would be greater than a US gal.

    Not even going to try to convert LPG mpg To Petrol mpg :Doh:
     
  10. johng

    johng Read Only Funster

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    hi Mo, I seemed to manage an average of 10 on my first ever trip 2 weeks ago..

    A different engine to yours..

    I suspect it was doing 15 on the motorway with wind behind, and more like 5 on the last bits of B road home..
    this was on Petrol as I hve my LPG disconnected and cant remember how to reconnnect it :Blush::Wink:
     
  11. old-mo

    old-mo Funster Extra Special Life Member

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    Thanks Geo,, The first time I topped up when the last green light was jumping from red to green it took 89 litres of LPG,, I have done 280 miles on the vehicle clock to a point it is doing the same,, so I assume on the 80% fill it is a 120litre tank,, which is about the same as I got with the 5th wheel and Ford F150..

    At the end of the day I am quite pleased cos with RV, trailer/car etc it must come in at about 7.3/4 ton to approx 8 ton...

    Then I may be wrong.. :Wink:
     
  12. old-mo

    old-mo Funster Extra Special Life Member

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    That sounds better than I had hoped for (I think) :thumb:







    Hi. johng..

    Dont you have a switch with 4 green lights and cant you switch from petrol to LPG with this switch??

    This one (which is new to me) and my old Ford truck are the same, :thumb:

    I did find going up some very steep hills (mountains) in the Sierra Nevada mountains that the engine hesitated and I did have to switch to petrol a few times,, but I was warned of this because so I was told the gas could not vapourise quick enough for what the engine was wanting to burn,especially at higher alltitudes, hence the hesitasion..

    Seemed to make sense to me and it only happened a few times.


    But I know nuffink.. :Blush:
     
  13. ehuplad

    ehuplad Read Only Funster

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    That sound to good to be true,

    We have a cheevy 8.1 gas getting around 8 on avarage

    If it is correct i want some of that

    Do not take any notice of the gauge for the gas they never work accuratly
     
    Last edited: Sep 11, 2009
  14. simsy56

    simsy56 Funster

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    Hi again, you are correct with the US gallon/ Imp gallon. Imp gallon is 1.2 US gallons. So, if the computer thingy is calibrated for US gallons, and you are getting 10mpg, per Imp gallon you are getting 12mpg, so thats even better!
    Craig.
     
  15. simsy56

    simsy56 Funster

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    Oh bye the way, the US mile is the same as ours, just their gallons are smaller.
     
  16. old-mo

    old-mo Funster Extra Special Life Member

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    Just pulled out the receipt from folder,,
    95.54 litres @ £0.569 litre = £54.36 did 280 mile round trip ? on a full to full LPG tank.
    afraid my brain is not capable of working out fuel used.. :Sad:
     
  17. johng

    johng Read Only Funster

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    Hi Mo, I do but, unfortunately I have had the Carb off and in peices 3 times (the first carb melted) :BigGrin:

    I am putting pipes back as best I can, the LPG is left unconnected but hope to have it all back together for the second monumentous journey, to Cornwall in Oct :Rofl1: I really want 20mpgs for that one!
     
  18. old-mo

    old-mo Funster Extra Special Life Member

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    Just out of curiosity, I have always filled up when the last green light is on or when it hovers between the red)Buzzer) and the first green..

    What happens if you dont fill up with gas (LPG) and that runs out,, does it automatically go onto petrol ?

    Thanks.
     
  19. old-mo

    old-mo Funster Extra Special Life Member

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    Wish you luck,, you seem to know a lot more than I do. enjoy Cornwall lovely county.. :thumb:
     
  20. simsy56

    simsy56 Funster

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    Hi Mo,

    Done some calculations, and

    £54.36p for 95.5litres(21.03gals) 280 miles= 13.333mpg

    £54.36p of petrol @£1.13/ litre = 10.59 gals @ 13.333mpg you travel 140.8 miles.

    l know there is an adjustment for running on lpg (less mpg) but, roughly you travel twice as far on lpg, than petrol. l think we all knew that. Only last week l saw lpg for sale at ASDA in Liverpool at 48.9/litre! So, if you had bought there you would have got 328.48 miles for your £54.36p. @ 13.333mpg.

    l think you are doing well at those sort of figures. Enjoy.

    Craig.
     

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