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LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 9:20 am
by weirdfish
As you know I have my car up for sale and have tried to be as honest as possible about the condition etc. I have also tried to be honest about running costs on lpg, i work it out at around 28mpg, no matter how you drive, it still seems to return the same mileage per tank full.
However, looking on ebay at a couple of 4.6's on lpg, they are claiming figures of 40 & 52 mpg, I must be doing something terribly wrong, or, they are telling a few porkies.
It costs me on average £50 to fill up, and I get 220 miles from that, tell me what you work that out to be, if you would be so kind, I pay 69p for the lpg.
Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 9:34 am
by graemeX5
Hi using the cops of LPG it's 13.662 and when using the unleaded rate of £1.319 a gallon it works out at 26.11.
I would say your being honest and others more overstating the situation.
Hth
Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 10:16 am
by IanP
Mine does 13mpg on gas, no way is it possible to get 40 mpg equivalent, unless they are getting LPG at a nice discount

Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 10:21 am
by weirdfish
I think what they may be doing is simply seeing what the computer is telling them and then doubling it, we all know that is the wrong way to work the real world mpg out, but boy does is sound good.
Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 4:17 pm
by weirdfish
Decided to ask how the seller works the mpg out for gas, found out that he is paying 58p per litre, makes a little more sense now, but still seems a tad high.
Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 4:51 pm
by Imy
Where can you get LPG for that cheap???
Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 5:49 pm
by weirdfish
My thoughts exactly, ok selling and stating mpg figures on the assumption that everyone can buy it that cheap, but we all know that's not the case.
I suppose if you're looking at buying something like this with LPG then hopefully you would have done a bit of research, and not take everything stated as gospel.
Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 7:12 pm
by Raj
One thing though, mpg is a measure of miles per gallon which is a constant irrelevant of cost. So whether he gets it for 10p or £1 the mpg will still be the same, or have I missed something?
Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 7:28 pm
by weirdfish
[quote="Raj"]
One thing though, mpg is a measure of miles per gallon which is a constant irrelevant of cost. So whether he gets it for 10p or £1 the mpg will still be the same, or have I missed something?
[/quote]
Am I missing something, surely it's about how many miles you get from how ever much you put in, you workout how many gallons of petrol the same amount, ( monetary wise ), that you have just put in at the LPG pump.
Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 8:13 pm
by Rob5
What people are trying to promote is the equivalent mpg of petrol vs lpg I reckon. If actual mpg is roughly the same on both, about 20 say, then for the equivalent cost of a full tank of petrol, lpg being half the price is the equivalent of 40 mpg.
Its not correct but I can see where they're coming from.
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Re: LPG figures on a 4.6is?
Posted: Sun Aug 12, 2012 8:46 pm
by weirdfish
[quote="Rob5"]
What people are trying to promote is the equivalent mpg of petrol vs lpg I reckon. If actual mpg is roughly the same on both, about 20 say, then for the equivalent cost of a full tank of petrol, lpg being half the price is the equivalent of 40 mpg.
Its not correct but I can see where they're coming from.
Sent from my GT-I9100 using Tapatalk 2
[/quote]
You are right in theory, and as long as the price of LPG is half the price of petrol, ( and quite often its not ), then yes, in theory it's double, but then you have to remember that you don't get the same return when running on gas, it's slightly yes, so that makes it even less than double.
Then you have to remember that you also need petrol as well to start the car, so that has to be factored in.
It made me smile as well in one of the eBay vehicles, they have stated that as long as the car is warm enough when you get back in it, then it will start up on gas. Never heard of that one before.
Re: LPG figures on a 4.6is?
Posted: Mon Aug 13, 2012 7:19 am
by shadrack
[quote="weirdfish"]
[quote="Rob5"]
What people are trying to promote is the equivalent mpg of petrol vs lpg I reckon. If actual mpg is roughly the same on both, about 20 say, then for the equivalent cost of a full tank of petrol, lpg being half the price is the equivalent of 40 mpg.
Its not correct but I can see where they're coming from.
Sent from my GT-I9100 using Tapatalk 2
[/quote]
You are right in theory, and as long as the price of LPG is half the price of petrol, ( and quite often its not ), then yes, in theory it's double, but then you have to remember that you don't get the same return when running on gas, it's slightly yes, so that makes it even less than double.
Then you have to remember that you also need petrol as well to start the car, so that has to be factored in.
It made me smile as well in one of the eBay vehicles, they have stated that as long as the car is warm enough when you get back in it, then it will start up on gas. Never heard of that one before.
[/quote]
My old 3.0i lpg used to start on gas if it was a relatively warm still or maybe it started on petrol but switched to gas within seconds, I worked it all out when I got my diesel and the lpg was marginally better but when I factored in that lpg filling stations are scarce in my area I got a diesel. Lpg is great for running 4.6s etc without it costing you the same a month as a morgage! As raj says the mpg is the same what their trying to say I'd how much cheaper they are to run, mine averages 19 mpg but cost £40 to fill so whn got 230 miles for 40 where as on petrol that would have cost £75, the other problem had was the price of lpg varies by so much at the time I had mine morrisons was 59.9 a place I spotted no where near my house was 52.9 at a gas suppliers not a petrol station going on the motorway it wad up to 85ppl so it was a little bit of a night mare, obviously the petrol for start up costs a lot if you do lots of small journeys as mine from cold did 5 miles or so on petrol weather you were goin 10 miles or 500 miles, one journey that made me smile in it was middlesbough to south hampton return for £105! Try doing that in a supermini its 646 miles!
Re: LPG figures on a 4.6is?
Posted: Mon Aug 13, 2012 7:27 am
by Raj
[quote="weirdfish"]
[quote="Raj"]
One thing though, mpg is a measure of miles per gallon which is a constant irrelevant of cost. So whether he gets it for 10p or £1 the mpg will still be the same, or have I missed something?
[/quote]
Am I missing something, surely it's about how many miles you get from how ever much you put in, you workout how many gallons of petrol the same amount, ( monetary wise ), that you have just put in at the LPG pump.
[/quote]
I agree, but when the cost of LPG can vary as does the price of petrol then it becomes an erroneous factor surely.
It's far better to state that for an equivalent 10 gallons of each fuel type will get you X amount of miles but then factor in fuel cost differences and so approx equivalent.
Re: LPG figures on a 4.6is?
Posted: Mon Aug 13, 2012 9:30 am
by weirdfish
As with any item you sell, you try to make yours look more attractive than anyone else's, but to make false statements is basically wrong, we all know that even if you drive these things like Miss Daisy you will struggle to realise the figures thay have stated.
The only way to work out the actual mileage is to, as you say, see what mileage you get from a said amount of fuel, and that is what I've done.
Have just had an email back from the seller of the one that states 40mpg, he says that he states that the car does 20mpg, so with LPG half price that makes it double, hence 40mpg, if only things were that simple in life. Lol.
LPG figures on a 4.6is?
Posted: Mon Aug 13, 2012 9:39 am
by Rusty
Nice try seller.
Trouble is, the uneducated would easily buy into these claims and then be very disappointed. That would make an unhappy X owner and further fuel the anti 4x4 crew.
Wouldn't take too much to correctly advertise surely?
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