What do you get?? "MPG.." (1 Viewer)

old-mo

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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 ?
 

Lampie

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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
 

savantuk

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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.

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Geo

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

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Sorry Mo those numbers do not add up to me


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..
 
Nov 6, 2008
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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.

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old-mo

old-mo

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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.

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.. ::bigsmile:
 

Geo

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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
 

scotjimland

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

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:

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johng

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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::winky:
 
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old-mo

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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

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.. :winky:
 
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old-mo

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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:




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






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::winky:


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:

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ehuplad

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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
 
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Nov 6, 2008
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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.
 
Nov 6, 2008
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Oh bye the way, the US mile is the same as ours, just their gallons are smaller.

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old-mo

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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


Just pulled out the receipt from folder,,
95.54 litres @ ÂŁ0.569 litre = ÂŁ54.36 did 280 mile round trip ? on a full to full LPG tank.
afraid my brain is not capable of working out fuel used.. :Sad:
 

johng

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


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

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 :ROFLMAO: I really want 20mpgs for that one!
 
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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


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.

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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) ::bigsmile:

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 :ROFLMAO: I really want 20mpgs for that one!



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

Done some calculations, and

ÂŁ54.36p for 95.5litres(21.03gals) 280 miles= 13.333mpg

ÂŁ54.36p of petrol @ÂŁ1.13/ 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 ÂŁ54.36p. @ 13.333mpg.

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

Craig.
 
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When l say travel twice as far, l mean in monetary terms, not, economy.

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dazzer

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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.

No it wont switch over automatically (at least the 2 LPG systems ive had didnt!!) You will gradually loose power as the gas runs out and have to flick the switch over to run on petrol. :thumb:
 
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old-mo

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Hi Mo,

Done some calculations, and

ÂŁ54.36p for 95.5litres(21.03gals) 280 miles= 13.333mpg

ÂŁ54.36p of petrol @ÂŁ1.13/ 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 ÂŁ54.36p. @ 13.333mpg.

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

Craig.

When l say travel twice as far, l mean in monetary terms, not, economy.




Great big thanks,,

That will do me.. :thumb:

I would never have been able to work that out.

I owe you a :drink:

Maurice.
 

johng

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Wish you luck,, you seem to know a lot more than I do


:Smile: I am Learning Mo.. I have always had older vehicles and always worked on them..
to be honest, 80's US is quite straightforward so far.. touch wood

Cornwall, a long weekend, was supposed to go at end of August but chickened out :)

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Jul 29, 2007
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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:

Hi Mo, no that's not right, if the gas can't vapourise quickly enough then they haven't fitted a big enough vapouriser, very often on the V8 the converters will fit two, one for each bank.

I have hammered mine up hill into a headwind towing a car trailer, flat out at around 65mph with no hint of a hesitation. I am afraid they are telling you porkies.

Easiest way to gauge LPG consumption is over a few fills, keeping a note of the mileage, my gauge has shown under 3mph going up hills in Switzerland:cry:, and over 30mph going down them. ::bigsmile: You can change it to read in Litres rather than US gallons if you like, but that won't show you what its doing on LPG.

Olley
 
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Better than driving an RV?.................Never ::bigsmile:

Olley

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Hi Mo, no that's not right, if the gas can't vapourise quickly enough then they haven't fitted a big enough vapouriser, very often on the V8 the converters will fit two, one for each bank.

I have hammered mine up hill into a headwind towing a car trailer, flat out at around 65mph with no hint of a hesitation. I am afraid they are telling you porkies.

Olley


Cheers "Olley"..

That`s probably what it was then,,

Irrelevant now, as that was with the Ford F150, going through the Sierra Nevada mountains.. there is a horrible long drag going out of Weymouth and it did used to hesitate on this hill,, I used to switch it over to petrol till I was on the top of the hill.

Not had the new one up any steep hills yet, but it never blinked the few times I `ve been up same hill out of Weymouth,, so perhaps this has got them twin vapouriser thingy`s. :thumb:


Thanks for all the advise and help guy`s.. :thumb:

Where would I and a lot of others be without you.. :Smile:
 

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