petrol lpg

zimzimmer

Member
Hi guys

i was just wondering if theres any 1.4 a2s on here running lpg. what are your thoughts reliability and economy wise??

ideally i have my heart set on a 75 tdi as i do from around 250-500 miles a week.

regards J
 
I have converted cars to LPG myself, starting in the 1970's. I have my own LPG filling facility, too. Although I own a Mercedes 190 converted to LPG, I have not used that vehicle for about 3-4 years. It is not feasible to run an A2 on LPG when calculating the relative economy gain to be had over the (already very economic) diesel. To be taken into account is not only the cost of conversion (~£1500), but the increased road-fund (£30 > £100) There is the additional mass of the steel tank and LPG to detract from economy, too. You will only get about 80% of the equivalent mpg of the petrol version, because on a volume basis, there is that drop in energy. Further, even with a "doughnut" type of tank, then there is a loss of carrying capacity. No, believe me, it really isn't feasible to do (or I would already be there!) LOL!

David
 
No that's not correct David, it is technically feasible and has been done. Whether it's economically beneficial or justifiable in money-terms is another matter.
 
No that's not correct David, it is technically feasible and has been done. Whether it's economically beneficial or justifiable in money-terms is another matter.

I think David appreciates that it's technically possible but is arguing against it for the latter reasons...

No, believe me, it really isn't feasible to do (or I would already be there!)

I think that's perhaps a little too categorical, David. Like you, I drive a TDI, but I know of a few club members who drive LPG-converted 1.4 petrols and are extremely pleased with them. If boot space is of lesser importance, or if the quick warm-up time of the petrol is beneficial, then there's nothing infeasible about it.
The 1.4 petrol is so much more common than the TDI, but the demand for them is so much lower. As such, a young, low-mileage example with a bit of spec' can be found with much greater ease and for much less money. Sure, you then pay for the conversion, but you've then got a car that's costing the same to fuel as an 80mpg diesel. It's not what I'd want, but I certainly see the attraction.

Tom
 
Look, I have done my sums, and compared to the diesel A2, there just aren't that great a saving to be made. That was my argument. Of course it CAN be done, mechanically! Now, if you've already got a petrol A2, then converting to LPG might just be worth considering ... but even then, it would be better to sell the petrol car and purchase a good diesel. I have said that I have my own LPG filling facility. What that means is that I can quickly fill any LPG powered vehicle from my house. The LPG is intended for domestic use. If it is used for cars, then a separate "Auto" tax has to be paid on that part of it, to H.M. taxes and excise. That is a fairly nominal tax and the total fuel cost is still only 50-55 pence-per-litre. Even with that very low fuel cost, I'm staying with my diesel A2! As I have said, I've done my sums!

David
 
In my experience, LPG can be good, but there are many things to consider as above. Converting a Petrol to LPG or buying a diesel may be a close call, but some people (me for example) may simply prefer the quieter sound of a petrol engine, or have a sentimental attachement to a well maintained car or have other reasons to want the petrol.

The most cost effective way to run around on LPG is to buy a car that has already been converted at the expense of someone else, as long as it has an LPGA certificate (or is on the register) or your insurance co may not touch it. They usually transfer only a small value across when you sell, so its only worth doing on a car that is young enough, and will be used enough, to cover a significant number of miles. Cant be many LPG converted A2's on the market though....!

The (probably only) great thing about increasing fuel prices is that although the cost of LPG has doubled in the last 10 years, and now hovers around 70ppl, the cost of petrol has also gone up two fold, which means running an LPG car now, actually saves more fuel costs than ever before. But thats after its installed, you've lost your boot space, informed your insurance and ensured there are a good supply of LPG stations on your usual routes (which is likely as they're quite well spread now)...... You always get a little less power on LPG too, so factor in around 10% drop in MPG to your numbers. Also you will start and run the first few miles on petrol, so still need to buy some of the expensive stuff from time to time.

I've had quite a few V8 A8/S8's on gas, and it was economical motoring (relitively), mainly because I bought them pre converted at little extra cost. I've never personally considered converting a car though as I know I wouldnt keep it long enough to get the value back :)
 
some people (me for example) may simply prefer the quieter sound of a petrol engine

Cant be many LPG converted A2's on the market though....!

You always get a little less power on LPG too, so factor in around 10% drop in MPG to your numbers.

Also you will start and run the first few miles on petrol, so still need to buy some of the expensive stuff from time to time.

A few points that I've highlighted ....

Yes, I do agree with the greater refinement of an LPG converted, petrol, Audi A2. My partners A2 (petrol) is SO much more refined than my Diesel!

There must be very few LPG converted A2's in total! Single figures?

I would say, from personal experience, that a 10% drop in MPG is on the conservative side .... I think that it is nearer to 20% .....

It is possible to have an installation that allows direct starting on LPG. In fact, my own Mercedes 190 has just such a system! There is a switch position (centre) on the petrol/lpg selector switch that allows direct starting on lpg! I never purchased any petrol over 2 years of running on LPG .... the petrol gauge always stayed dead-centre!

Now, obviously, the higher a vehicles fuel consumption is, then the more attractive a conversion will be to LPG. That is why there are so many Range-Rovers' converted to LPG! Payback will then occur in a much shorter time! It is possible to (partly) convert a diesel car to LPG. However, the LPG content is limited to about 35% of the total fuel used. It CAN be done!

David
 
Happy with my LPG converted car. 1.4, the cost to convert was £1000 about 3 years ago but for various reasons my fitter has actually cut fitting cost or stayed the same.

I get my LPG on account with a small discount from the cheap 62 pence per litre to the much better 56pence.

At that price the numbers are a little better. My only economy run in 3 years (60 or 3k revs on the motorway) yielded and equivalent mpg of 98. This was calculated relative to the price of petrol. If it was calculated relative to the price of diesel the figure would be better.

The tank that was fitted was a 50 litre tank that was fitted to the sub floor of the boot so I still have hatchback functionality. Battery access is compromised.

30K miles so far for me.
 
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My only economy run in 3 years (60 or 3k revs on the motorway) yielded and equivalent mpg of 98. This was calculated relative to the price of petrol.

.

I'm sorry, but I think that figure may be wrong? Lets assume that a petrol A2 averages 40 mpg and that petrol is 130 ppl. Lets take your LPG cost as 60 ppl. Lets also assume that you will loose about 20% mpg because there isn't the same energy in LPG. So you will travel 34 miles for an LPG cost of £2.70 (or 40 miles for a cost of £3.18). For the cost of 1 gallon of petrol, you should then travel 5.85/3.18 x 40 = 74 mpg. This is still good, but not quite that 98 mpg! However, the savings are £2.67 for every 40 miles travelled. That equates to payback of your installation (£1000) in 15,000 miles. So you've paid it back twice over! Oh, there is the slight saving of £30 for a certified LPG vehicle on road-fund, I believe.
 
Lets assume that a petrol A2 averages 40 mpg and that petrol is 130 ppl. Lets take your LPG cost as 60 ppl. Lets also assume that you will loose about 20% mpg because there isn't the same energy in LPG. So you will travel 34 miles for an LPG cost of £2.70 (or 40 miles for a cost of £3.18). For the cost of 1 gallon of petrol, you should then travel 5.85/3.18 x 40 = 74 mpg.

That looks right to me. 98mpg equivalent did seem extraordinarily good.
 
Lets assume that a petrol A2 averages 40 mpg .......and that petrol is 130 ppl. .........Lets take your LPG cost as 60 ppl. Lets also assume that you will loose about 20% mpg because there isn't the same energy in LPG.

Given these 3 assumptions you are correct.

Most of my driving is local and I am lucky that I have a local supplier who offers a discount to account holders (currently 56ppl).

I pay £100 minimum in advance and if the price of lpg goes up I still pay the lower price I bought it at . If the price goes down (rare but has happened) I pay the lower price.:)

Oh! I never factored into my calculation that they hold a prize draw for free fuel which I won once so that fuel was free:)
 
Indeed... there's a member local to me who uses his 1.4 petrol for motorway commuting, and he averages 53mpg. So, on that basis, and with Dougie's extra LPG discounts, 98mpg equivalent is feasible.

Either way, it's cheap motoring.
 
The figure is real but glossy.

It was a long boring run back from Cornwall and mostly pretty flat. I used the price I would pay if back home. Best case scenario to figure out what was possible.

I don't like to think about it to much as I want to drive my car the way I like. Round here it is pretty hilly too.

I used a figure of 138ppl (is that correct?) Divided by 56ppl = 2.464.... X 53mpg =130mpg Wow.........
 
Either way, it's cheap motoring.

Don't forget, we are comparing LPG with a petrol car, here .... If you do the same sums with a diesel car, then any gains really are minimal .... and the road-fund for a diesel A2 is £30! Oh, Insurance is significantly lower, too! Compared with a diesel, I doubt that you would ever get "payback" for the installation costs! (I gather that £1500-£1800 is more typical for an LPG system, by the way)

David
 
Don't forget, we are comparing LPG with a petrol car, here .... If you do the same sums with a diesel car, then any gains really are minimal ....
Oh, Insurance is significantly lower, too!
(I gather that £1500-£1800 is more typical for an LPG system, by the way)

David

Hi David, I accept what you are saying about relative to a diesels mpg it is different. Diesel cars do however cost more to buy outright and the fuel is a little dearer.
What do you currently pay for insurance?
The conversion was done in south Wales. In Poland (where they really are skint) LPG is very popular. A pole set up here and brought over mechanics who did an amazing job.

Unfortunately they have accessed his database of customers :mad: and are 'competing' on price and set up rival companies. So much so that he is in the process of relocating to the midlands.

£1000 was the price 3 years ago, don't know how much these rivals are charging now.
 
Yes, I know the very Guy! "Profesgas", I seem to recall .... I've been there! Someone I know from the Chorus that I sing with .... his Daughter had a Honda Civic converted by them . Unfortunately, it has proved very troublesome .... Oh well ....

David
 
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