LPG conversion - chicken and egg runaround

And if they optimised it for performance, how come aftermarket tuning add ons increase power?

They usually do so by sacrificing economy, reliability, or to be entirely sane about it instead of constructing a strawman, to shift the product's attributes into a different market segment that would affect the original manufacturer's planned profits, marketing and targets like average economy, noise, and insurance grouping. Also, fairly often the aftermarket tuning bits either don't work (and make feeble gains), or cost a hell of a lot more than buying the better-spec car in the first place, or do both. Whilst not including the sort of detail upgrades to the car's powertrain, engine internals and so forth that the manufacturer would have done to ensure reliability, safety, yadda yadda.

I hear MR2 Turbos aren't that reliable, especially if tuned up. Can't remember who told me that one, though...

Richard

You're doing it wrong, you're supposed to say "40mpg". That's how every bootless, shagged out old Mercedes 300 or Range Rover I find with LPG tanks rendering the fact that they're a practical estate car utterly irrelevant is marketed, despite the fact that their worn out old big engines are struggling to approach the power outputs people buy the cars for in the first place whilst genuinely returning 18mpg or less. Yes. Those gallons cost less, for now.

A lot of people also pour chipfat in their diesel cars to save a quid or two, so I don't think that this is entirely true. I think that it could be argued that /new/ car buyers, not being desperate to save money in remarkably convoluted ways, are less convinced by LPG as a long-term economy measure.

Some peope point to the environmental benefits of LPG. They are overstated.

If you can't afford to fuel something with a large engine, then find something interesting you can afford to fuel. If you're so miserly that spending £800-1000+ on plumbing and sacrificing space in your car for a volatile pressurised container seems like a good idea (especially since statistically the sort of user that has these cars also keeps them for a relatively short period), then your priority is not enjoying a large engined car, it's saving money.

Not excessively, IIRC, especially since the models were targeted at the fleet market and early Congestion Charge incentives.

Some are CNG, dual fuel (still a bifuel system though) and they are also Flexfuel - can run Ethanol. But FWIW, Ethanol - Alcool - is a perfectly valid fuel without needing to be blended or indeed, dual fuel because the secondary one can't actually start the car from cold without massive changes in how the engine works.

Producing Alcool is a bit of a headache though.

Richard

Very well, show me a pure LPG car offered in the UK market. Not a dual fuel car and not a forklift.

As long as the LPG is still available. But the gas can also be used for heating properties - it's not like there is no demand for it. Increase demand for LPG by having more LPG cars, alter the demand elsewhere for different products.

The tax on LPG - or the lack thereof - is what actually makes LPG conversions attractive. LPG is taxed at between 13 and 16 pence per Kg, and a Kg is roughly equivalent to a gallon. So 16 pence duty /per gallon/ is essentially the same as 4p (again, roughly, I trust you're not going to be such a plonker as to suggest I can't work it out accurately) duty per litre of petrol.

Which would make a litre of petrol - even now - about 55-60p.

From the environmental point of view, I'm tempted to research how much crude yields how much petrol, diesel and LPG respectively. As a refined product LPG is increasing in cost daily. All it would take is for the Government to decide to tax its use as a road fuel and this whole mess of plumbing and wasted interior volume for tanks would be pointless.

Duty on Biofuels is 20p lower, but the cost of producing and marketing them is higher.

Richard

They spend a lot of money developing but I don't think power is the only thing they are optimising for. Noise, economy and emissions will play a part too.

I don't think most aftermarket induction and fuelling tuning add ons do increase performance much on modern normally aspirated cars.

Jings how could I guess that you blart out that without bothering to look for yourself?

So I look forward to an "I'm sorry for the tone of my reply" from you.

There's the Smart for Two LPG, it's not dual fuel because there's no room for two full size tanks. They cost £13000 each which means that there are virtually no sales except to die-hard congestion charge dodgers. There is also a dual fuel conversion which involves having a tiny petrol tank added, but that's not the one I'm talking about so don't come up with an advert for a dual fuel Smart and come over all smug. OK?

There is, or was, a Corsa LPG which was LPG only, heavens knows if they still bother to make it.

There was also an LPG only version of the Mercedes 380SEL, and of the Mitsubishi Galant and a CNG only version of the Volvo S80. Sulzer owned a fleet of the latter.

Because you'd assume I'd already looked?

I'm sorry for the tone of your reply.

Well, if you want to provide me with more /detailed/ information about it, it'd be handy - since all I can find is information about the Smart LPG which has the tiny petrol tank. Having searched a fair bit, even with the additional information all I'm finding are bifuel cars (such as the S80 BiFuel) - not even any press info from Volvo or similar relating to fleets of LPG cars.

So, at best, I'd say that the manufacturer's offerings of pure LPG cars in the UK are about as relevant as Fuel Cell Vehicles in the USA and Japan. Yes, they exist, and people have used them, but they are fundamentally an experiment.

Richard

So which bit of my original post where I made the same point did you not understand? Perhaps if you tried to stop being a smartarse -

No doubt, but you know better than to make such a statement like that on here without checking it out first, or leaving yourself a get out clause, as someone will always pedant you on a technicality hehe!

:-)

...then you'd have the position entirely to yourself?

I notice you don't address the salient points of the post regarding the costing/taxation of the fuel.

Richard

Eh, I'm perfectly happy to be proven wrong - I can't know /everything/ about cars, and tbh even if I did pick up a magazine with some PR about a pure LPG car being run in a fleet, I'd be quite likely to be distracted by something like "Rover introduce RWD V8 estate car" or "Volvo 480's existence still denied by Volvo PR firms, choosing to skip from P1800 to C70 to C30".

I'd quite like to see technical information about the pure LPG cars; how they cold start, how they run, how reliable they were, what sort of running costs they incurred... alternative (even if they're not THAT alternative) fuels interest me, I rather like the idea of cars not vanishing with the oil running out.

Richard

Don't we all? LPG is only really a temporary solution - biofuels are a slightly better one, but there's still the issue (in terms of biodiesel) of it solidifying a bit in very cold conditions, and relying on the availability of regular diesel to at least run a 50/50 mix. Fuel cell is ultimately the way to go, but it's a matter of the technology being readily enough available for the cost to come down a huge amount to make it viable.

For now, I'll stick to LPG in the van at least - when I bought it LPG was virtually bang on half the price of diesel, now it's a good few pence/litre less than half the price, whilst still doing the same mpg vs diesel. And IMHO, that gap can only increase. (See my other much longer post, which I typed before this, but haven't clicked send on yet, for why I don't think LPG can suddenly get a huge duty hike).

Don't know where you get that bit from. I'm not disputing the 13-16p/kg figure, but a very quick bit of googling suggests that LPG's density is

0.538kg/litre. Doesn't equate to a kg being anywhere close to a gallon.

Doubt it - don't know off the top of my head the exact figure for the duty, per litre, of petrol - yes, it'd be a damn sight cheaper, but the base price of LPG is still a fair bit cheaper owing to the fact that it's a by-product and production costs are [allegedly] lower.

Thing is, as I've said before - I don't reckon the consumer cost of LPG can increase much more, as people would just switch back to diesel. Take my van as an example - on petrol it does 18mpg, compared to a diesel which'd do

28mpg. That's about 35% less on petrol for something with broadly similar power. Knock off 20% and you're down to pretty much half the mpg on LPG compared to diesel. Therefore, LPG needs to be half the price of diesel to make it worth anyone's while, and even then, it's only really going to be attractive if pre-converted cars are about the same price to buy new, or only attractive to people buying them second-hand with a decent conversion already in place. Then you've got the crap range - only really solvable with a big tank, which is only practical if it's something like a big van or a Rangie, where you can put decent size underslung tanks in without sacrificing load space.

In short, yes, LPG is basically a cost-saving thing, but it's not quite on a par with running a diesel on neat used veg oil. It's still a clean burning fuel that's not going to gum up injection systems like the other will. My point being that a properly LPG converted petrol engine isn't the "pikey option" to anywhere near the same degree as a diesel one run on chip fat. Yes, they can attract that type of person, which basically means be careful when buying. Just like any car....

I'd found figures suggesting 5lb=... Ah, yes, forgot a stage. It was late. Oh well, if anything that suggests a duty of roughly 8 pence per litre.

Correct figures for LPG would make it 8p/litre for duty, so at 60p, the LPG is costing 52p without duty, and is only attracting 8% VAT.

The duty on fuel is 53p per litre, and 17.5% VAT - IIRC the total tax component at the pumps is about 68% now, it might be a bit lower. Either way, a really quick rough calculation says "Remove the VAT on £1.18 and you get £1, take away 53p and you get 47p for the fuel at the pump, without the duties levied".

I can see it making far more sense on a van where the tanks can be fitted underneath, and the user is liable to be doing 30-40,000 miles per year, than on a large luxury car doing average mileage. Just trading said luxury car in for a diesel equivalent (can't afford to run a Lexus? Get an Audi A8 TDi then).

LPG's duty is increasing. It's only a matter of time before Labour find a way of reclassifying LPG sold for passenger cars and sticking full VAT on it.

Richard

Monkey - DIYers are usually not monkeys - but I can think of a couple of pro installers around the country, notably the north west one.

Also this shows your lack of knowleage of the modern SGI system.

When the gas injectors squirt very near the petrol ones, also the control is done by the cars original ECU the LPG ECU just has to apply fuel trims, there are little changes from the perol system.

Try pulling a large caravan with an economy hatch, also more room for the children. I also happen to like the halving of fuel bills/.

I doubt this with modern SGI systems. Also how about the complete lack of particulates.

Vauxhall Semi Synthetic and Michelin Primacys here

Huge boot so about a 1/4, anyway you are not having because I am not selling

Oh. A caravan, too. Yeah, you'd probably halve your fuel bills if you didn't haul that about.

This will now cease to be any sort of technical discussion and will degenerate into a religious war, clearly, since you have a caravan and consider children to need more "room" than the meagre space they occupy in the actual seat (IME, they fit in a 924S just fine). Our faiths are mutually incompatible. You're an alien species to me.

Richard

I noti e that you didn't read my original post, b ut just ascended onto your soap box and burbled the same old crap.