Dual fuel Petrol/LPG and ML

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As I remember the company ordered about 6 Vectras on LPG,they did not come off the production line as LPG,but were then sent to Millbrook to be converted,I know I picked up the first one there,that 1.8 vectra used to return in money terms 43 mpg,on petrol she would do 32 mpg,of course the big 4x4's like Porsche,and RR's I suppose they would return mid 20's on LPG,you would think it would be promoted more as it is a clean fuel,if I bought at big 4x4 I would consider it but you do have to put the miles in to get the £1600 pound conversion.
 
I've just bought a ML55 running on gas. Its awesome! 600 mile trip to Cornwall on £90 of gas, and that was pushing it a bit.
I would certainly buy another, LPG cars are the best kept secret. But if you are only doing 2-4 miles you may not get the benefit as the car starts, and runs until warm on petrol.
 
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Had our Jeep converted as soon as we got it. IIRC the tank is 105l and sits where the spare wheel used to underneath so no loss of space in the back. I honestly can't tell any diference between it running on petrol or LPG. Gives about 10% less mpg than petrol but of course it's significantly cheaper to buy. It's the 5.7 V8 and on the short runs we do gives about 300 miles on a full tank of gas plus a small amount of petrol it uses for starting and initial warmup to about 40 degrees.

Another small bonus is the (very) small reduction in RFL and if you drive it into the MOT test on gas, they don't need to do an emissions test.

One thing you can't beat is the warm fuzzy feeling you get from filling it up for significantly less then the £100 it would cost for petrol.
 
How much is LPG per litre vs petrol?

I pay 1.32 per litre of diesel V-Power.
 
How much is LPG per litre vs petrol?

I pay 1.32 per litre of diesel V-Power.
Not an entirely valid comparison as LPG is less " energy dense"than liquid hydrocarbon fuels. MPG comes in about 20% less on a volume basis. In that respect its inferior to its petrol and diesel equivalents. Its advantage derives from its clean burn characteristics and more favourable tax status--- for now. :rolleyes:
http://www.drivelpg.co.uk/about-autogas/
 
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Well the price is not half that of petrol/diesel around here with little competition it is 58p a litre,of course you can buy it a lot cheaper,I no longer have the LPG car but driving through the fens from Soham to Somersham on the A1123 thus avoiding the mayhem on the A14/A1 junction I noticed a farm complex with a sign LPG here no price,but I bet that was cheap,also when I did have to LPG car I found South Wales had cheap LPG,there are quiet a few garages selling it ,you can download a map for your sat nav,to be fair if you have a big engine car and do the miles then the cost of the conversion is soon covered,as I say the draw backs waiting to get on the only pump and when it is very cold you have to stand there with your finger on the fill button until icicles form also if freezing the pump may not work as the LPG tank at the garage is frozen or the lines to the pump,but that only happened to me once but something to consider in the artic north of the country.
 
grober said:
Not an entirely valid comparison as LPG is less " energy dense"than liquid hydrocarbon fuels. MPG comes in about 20% less on a volume basis. In that respect its inferior to its petrol and diesel equivalents. Its advantage derives from its clean burn characteristics and more favourable tax status--- for now. :rolleyes: http://www.drivelpg.co.uk/about-autogas/[/

Not true really. Lpg systems came a long way, lpg burns cleaner and more efficient. Proper installers will tune the car either live or on dyno and will prove you wrong. Unforunetally UK installers are way behind in the subject. Would never get a car converted here. My two pennys
 
How much is LPG per litre vs petrol?

I pay 1.32 per litre of diesel V-Power.

The price of LPG varies in much the same way as diesel/unleaded. My last fill at a Sainsbury's fuel station near me was 56.9p per litre, I'd say average around my way is 54.9-59.9p at the moment, was 49.9p locally for a long time but then unleaded/diesel has gone up by 10-20p over the last year or two.

At the end of the day it's always going to be loads cheaper to run on gas, whether it has a marginally lower calorific value or slightly lower equivalent mpg compared to a litre of petrol.

55-60p vs £1.20/1.30 - you've saving about £50 a tank to begin with :)
 
That's helpful and puts things into perspective! :)
 
Hi,

Ive had several cars converted to LPG. Some engines / heads need flash lube, some dont. Also, I noticed less mpg per gas than I did petrol. So my old car was 26 mpg on petrol, it did 20 mpg on lpg, so there is a slight different.

I would install LPG again but you then to travel a certain distance to make it worth while. I think there is an LPG calculator out there on the net which will explian.

i.e. my old v6 installation costs was around £2K with auto flashlube. I needed to travel 20K miles to make the LPG worth while.

Im certainly a gas fan but you need to be aware that ferries / trains need to be told, and you need to register the car as a LPG to get the London congestion charge reduction.

Takes for ever to fill the tanks though, especially in winter :)

Simon
 
sbk1972 said:
Hi, Ive had several cars converted to LPG. Some engines / heads need flash lube, some dont. Also, I noticed less mpg per gas than I did petrol. So my old car was 26 mpg on petrol, it did 20 mpg on lpg, so there is a slight different. I would install LPG again but you then to travel a certain distance to make it worth while. I think there is an LPG calculator out there on the net which will explian. i.e. my old v6 installation costs was around £2K with auto flashlube. I needed to travel 20K miles to make the LPG worth while. Im certainly a gas fan but you need to be aware that ferries / trains need to be told, and you need to register the car as a LPG to get the London congestion charge reduction. Takes for ever to fill the tanks though, especially in winter :) Simon

Yes that is exactly how it looked like with old type of installations. Not now.
Why it takes forever to fill up - Had 4 cars on lpg never a problem. Mpg no difference. It never cost me more then 1500£ to install for top of the range system
 
As a comparison.

My old C230K

55 litres of petrol gave me a range of 280 miles at say £65
63 litres of LPG gave me a range of 280 miles at say £31.50 plus a tenner of petrol whilst warming up per tank, so with me on average I saved a third on fuel costs. Doing 15k a year was not really cost effective to pay to get converted but as I only paid £1200 for the whole car with the LPG already on it and it came with a complete C36 Kit, arch spats, C36 exhaust and monoblocks it was a no brainer !
 
I used to run a Saab 9-3 with lpg, it was a Prinz system and worked very well for the short time i owned it, but was told by a Saab specialist that when the system was fitted, where did all the swarf go from installing the extra injectors as nearly all systems are fitted without removing the cylinder heads, made me think!!
 
I used to run a Saab 9-3 with lpg, it was a Prinz system and worked very well for the short time i owned it, but was told by a Saab specialist that when the system was fitted, where did all the swarf go from installing the extra injectors as nearly all systems are fitted without removing the cylinder heads, made me think!!

That is a old chestnut they use a special drill which sucks the swarf out as it is made,what you have to be careful of is presenting a car that the LPG garage has never changed before,always look at the installation pictures if they are neat fine,some look like a demented monkey has fitted the system ,all this talk has started me looking at a RR sport already on LPG, I just do not do the mileage now to warrant paying for a V8 conversion,if it is still for sale at the weekend I will see it as a sign.:D
 
Borys said:
Yes that is exactly how it looked like with old type of installations. Not now. Why it takes forever to fill up - Had 4 cars on lpg never a problem. Mpg no difference. It never cost me more then 1500£ to install for top of the range system
Where did you get the install done?
 
I run a 4.5l cayenne on lpg and we need to get rid simply because of the lack of boot space due to the 90l tank. The reduced fuel costs will be missed!!
 
That is a old chestnut they use a special drill which sucks the swarf out as it is made,what you have to be careful of is presenting a car that the LPG garage has never changed before,always look at the installation pictures if they are neat fine,some look like a demented monkey has fitted the system ,all this talk has started me looking at a RR sport already on LPG, I just do not do the mileage now to warrant paying for a V8 conversion,if it is still for sale at the weekend I will see it as a sign.:D

How does this special drill work, intrigued as I have a job coming up where this would be beneficial
 
Why it takes forever to fill up - Had 4 cars on lpg never a problem.

I've never understood this either, can't say I've noticed it taking any longer to fill - not enough to comment anyway. At least you don't get greasy hands like at the diesel pumps! Perhaps people perceive it to take longer than it actually does to fill because the £ signs spin round much slower! :)

I used to run a Saab 9-3 with lpg, it was a Prinz system and worked very well for the short time i owned it, but was told by a Saab specialist that when the system was fitted, where did all the swarf go from installing the extra injectors as nearly all systems are fitted without removing the cylinder heads, made me think!!

Cylinder heads? Are you sure he didn't mean on the inlet manifold or something? I'd have thought anyone letting swarf into engines would not be in business very long! :eek:
 
I had a couple of V8's converted to LPG before I got the CLS, I do c 30,000 miles a year and without the conversion it wouldn't have been viable to run that sort of car.

If you are thinking about buying a converted car you should establish what sort of system is in the car and then make sure you there is someone local to you that can maintain it. There are many different systems out there and most LPG fitters/maintainers will only deal with one or two of them. There are also some good LPG forums that can help.

I did nearly 200,000 miles on the 2 cars I had converted without any real problems other than the loss of boot space, but that's what roof boxes are for
 
Just browsing and saw this really good and comprehensive French guide to LPG stations. It has updated prices and all the satnav locations. The UK website below seem much more basic but at least someone is trying to help.

Chercher des stations Pas de Calais - Annuaire des stations GPL françaises

LPG Autogas - the greener, cleaner and cheaper fuel alternative
 

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