LPG versus Petrol. What's your view

[turboute]

I seriously save $50 a week (400-450kms and that was 1 yr ago) now that I have converted to gas. I have not changed the type of oil I use however It does get changed every 5000km's. Given that a major service costs $150-$170 that means I am still saving $950 approx every 10,000kms. Believe me I am glad that I changed - I do about 25,000km's a year - so I save about $2500, considering it only cost me 1k to get the conversion I was better off by 1.5k in the first year.

[Pilch]

Originally Posted by MITCHAY

I travel about 300-400kms mostly peak hour traffic and when I am moving i flog the s**t of it. Lol and it produces a whopping 87kws but yet is still enough (I dont need a V8 supercar). Ive gone a week on $15 before but thats just too boring. I dont always put the same amount in every week. Sometimes ill put in $20 or $25 but mostly $30.

Well for comparison's sake (and don't take any of this personally, just the car you drive is a good comparison), my car achieves 19L/100km based on 80% city driving and makes 140rwkw on LPG. At let's say $0.40 (city priced LPG) I can travel 395km. That's in a full sized family sedan that's about 28 years old!

The point i'm making here is that when setup right, a full size V8 sedan would have to be compared to a small to medium sized basic vehicle to return the similar cost effectiveness.

NO, it's no scientific conclusion Red, but it's damned hard to argue with!!! I genuinely believe I can achieve that same fuel economy and be making upwards of 180rwkw too :

[niko]

if u want the power pay for it, factory motors are designed for petrol application gas is just bolted on these days, ignoring ford factory taxi's, so ofcourse petrol will run better.

there always the option of gas research or gas injection, and if u want more power build a motor to suit the fuel your using!

[Black XR6]

Originally Posted by RED_EL_XR8

Most fleet managers have done a lot more sums than the high school math you quote.

Funny,at a meeting of fleet managers at a fleet conferance there seemed to be praise for lpg. Check it out for yourself http://www.fleetnewsnet.co.uk/news/v...e&art_ID=27507

I did take up your challenge to search under lpg pitfalls and so far have failed to find a credible site that proclaims LPG is worse than regular petrol. I will keep looking though.

Looked through the first 6 pages of results from the search and found nothing. Entered a search for automotive lpg pitfalls and am still looking

[RED_EL_XR8]

Originally Posted by Black XR6

Funny,at a meeting of fleet managers at a fleet conferance there seemed to be praise for lpg. Check it out for yourself http://www.fleetnewsnet.co.uk/news/v...e&art_ID=27507

I did take up your challenge to search under lpg pitfalls and so far have failed to find a credible site that proclaims LPG is worse than regular petrol. I will keep looking though.

And that meeting of fleet-managers you quote is from which country?, and as such, about as relevant as the circumference of Jupiter in imperial measure, to any debate about Australian conditions.

[Black XR6]

Automotive engines have worked on basically the same principles for a very long time. I dont think it matters what country an engine is running in. If LPG is so bad there would be engines in all countries struggling with it. Its very relevant.

Explain how it isnt relevant?

[Sourbastard]

Originally Posted by Black XR6

Automotive engines have worked on basically the same principles for a very long time. I dont think it matters what country an engine is running in. If LPG is so bad there would be engines in all countries struggling with it. Its very relevant.

Explain how it isnt relevant?

the engines work along the same principals mate, but from one country to another you get vasty differing conditions in many areas. Climate and Altitude alone can make a difference on how well your car will run.

LPG is ok as a fuel, but like anything else is has draw backs. You name the fuel, it has a draw back. Expense, economy, power, maintainence, wear & component impact. These are all factors. No one fuel is perfect, but as a previous LPG runner myself, I know I prefer petrol.

And if anyone thinks LPG has no impact on an engine at all you are 100% wrong. All fuels have an impact on an engine, hence why so much is spent on their research. They just dont rip oil from the ground, wave a magic wand at it and turn it into the fuel of the week.

[GraveDilute]

I too did a search for lpg pitfalls.

pages and pages of irrelevant sites.....

[Black XR6]

Originally Posted by sourbastard

the engines work along the same principals mate, but from one country to another you get vasty differing conditions in many areas. Climate and Altitude alone can make a difference on how well your car will run.

LPG is ok as a fuel, but like anything else is has draw backs. You name the fuel, it has a draw back. Expense, economy, power, maintainence, wear & component impact. These are all factors. No one fuel is perfect, but as a previous LPG runner myself, I know I prefer petrol.

And if anyone thinks LPG has no impact on an engine at all you are 100% wrong. All fuels have an impact on an engine, hence why so much is spent on their research. They just dont rip oil from the ground, wave a magic wand at it and turn it into the fuel of the week.

Im not disputing an engine from another country will benefit or suffer from climate conditions, but this is not related to LPG wear is it? If LPG as has been stated causes certain engine components to fail then engines in other countries will see similar failures compared to their petrol driven counterparts.

And yes, every fuel has its pluses and minuses. But this is a comparrison between petrol and LPG and which is the better fuel not just from a price point of view but engine life as well. I just cant find anything written down that states LPG will harm your engine more than petrol.

[niko]

how is it possible that taxi's do so many k's and all i hear is them complaining about there autos only lasting 600,000 without attention *au's, and 350,000 in the ba's

[4.9 EF Futura]

Well its certainly an interesting thread. However, it would appear that members have been invited to comment on their opinion of LPG but then struck down for speaking against it?

I disagree that someone who does not run a vehicle on LPG is not qualified to comment. Someone who does not run it has obviously decided against the fuel - you are therefore suggesting that only LPG users are 'qualified' to comment and therefore striking out an entire set of opinions....? There are several reasons why I would not consider installing LPG on my car.

The forced induction setup. This is obviously going to require something a little more complex than a $1000 - $2000 conversion. This dramatically increases the 'payback' period - im not even sure I want to keep the car that long.

Inconsistency. Have a forced induction setup obviously requires quite a specific tune. How is this possible when the mix of propane to butane is not regulated? Without a complex tuning solution how does one account for varying octane ratings??

Boot space. Every now and then I like to pack up the picnic table, grab a few chairs and an esky and head out with the mates and a couple of lady friends for a day at the beach/races/whatever... now without removing the petrol tank (and therefore increasing the cost and payback period again) I can expect to lose 30% of that boot space.

Hassle. Can you blame the public for having a negative perception of LPG systems when you look at the number of people that have problems with their setups? I agree that its probably a simple matter of tuning and maintaining the system but once again, this adds to the cost of the setup and there's a lot of people that dont want to risk the car refusing to start due to a lack of maintenance - and would rather pay an extra 80c per litre. I cannot count on two hands the number of people that have consistent problems which can be attributed to the LPG setup.

The source of LPG. About 20% of our LPG occurs naturally - around oil resevoirs. Ironically, these natural sources of propane and butane are only utilised because we went their "to get the oil". The rest is a by product of petroleum production. My point? When oil runs out - so will LPG. As we are in the last years of fossil fuels I have chosen to enjoy them as opposed to spending these last years cursing the "bloody LPG system".

I am not attacking it as a fuel - but simply stating there are many reasons why someone would choose not to run it.

[Black XR6]

wow, an auto only lasting 600,00km or even 350,000km. That would be much longer than most private owners would own their cars.

Fleet matters are different but IF LPG is saving them so much by the time they have driven 600,000km they could buy several brand new transmissions.

[Pilch]

Originally Posted by 4.9 EF Futura

I disagree that someone who does not run a vehicle on LPG is not qualified to comment. Someone who does not run it has obviously decided against the fuel - you are therefore suggesting that only LPG users are 'qualified' to comment and therefore striking out an entire set of opinions....? There are several reasons why I would not consider installing LPG on my car.

Fair enough. While having first hand experience with LPG is definitly a positive, it by no means stops someone from having a well educated opinion and this is a forum after all!

Originally Posted by 4.9 EF Futura

The forced induction setup. This is obviously going to require something a little more complex than a $1000 - $2000 conversion. This dramatically increases the 'payback' period - im not even sure I want to keep the car that long.

Inconsistency. Have a forced induction setup obviously requires quite a specific tune. How is this possible when the mix of propane to butane is not regulated? Without a complex tuning solution how does one account for varying octane ratings??

Once again, fair call. To a large extent setting up a forced induction setup is more expensive because: 1. Less people do it, so less research and therefore higher setup cost, and 2. You have to convert from petrol, so it's gonna cost more regardless on this fact alone, and is the same in an N/A application.

As for octane variation due to butane and propane mix, this should be regulated, but at the same time I doubt you'll find many people that have had issues in this area. And it's the same with petrol, you won't buy 95ron from shell one day, and from BP the next if your system is fragile!!!

Originally Posted by 4.9 EF Futura

Boot space. Every now and then I like to pack up the picnic table, grab a few chairs and an esky and head out with the mates and a couple of lady friends for a day at the beach/races/whatever... now without removing the petrol tank (and therefore increasing the cost and payback period again) I can expect to lose 30% of that boot space.

Sure, it costs money to convert the petrol tank to an LPG tank, but it can be done and is no less efficient in the use of space than a petrol tank, don't you think? If car manurfacturers were to sell straight LPG vehicles (eg. the Falcon E-Gas) than this argument is irrelevant!!!

Originally Posted by 4.9 EF Futura

Hassle. Can you blame the public for having a negative perception of LPG systems when you look at the number of people that have problems with their setups? I agree that its probably a simple matter of tuning and maintaining the system but once again, this adds to the cost of the setup and there's a lot of people that dont want to risk the car refusing to start due to a lack of maintenance - and would rather pay an extra 80c per litre. I cannot count on two hands the number of people that have consistent problems which can be attributed to the LPG setup.

No, I don't blame the public opinion of LPG on the public at all. Unless cars are purpose built for running LPG, these problems will continue to occur. How do you think an E-Gas Falcon would run on petrol if converted and not modified to suit??? Not to well, the problem is setup and not the fuel.

Originally Posted by 4.9 EF Futura

The source of LPG. About 20% of our LPG occurs naturally - around oil resevoirs. Ironically, these natural sources of propane and butane are only utilised because we went their "to get the oil". The rest is a by product of petroleum production. My point? When oil runs out - so will LPG. As we are in the last years of fossil fuels I have chosen to enjoy them as opposed to spending these last years cursing the "bloody LPG system".

.... and some of us would prefer to deal with a "bloody LPG system" for the advantage of a $0.80 + saving per litre until oil reserves are depleted.

Seriously though mate, atleast you've put a constructive argument down!!!

I'd honestly say Petrol is a better fuel in general, but because of prices and lower emmisions LPG is the winning fuel TODAY!

[4.9 EF Futura]

Originally Posted by Pilch

I'd honestly say Petrol is a better fuel in general, but because of prices and lower emmisions LPG is the winning fuel TODAY!

That's a well-put statement.

And yes - $1.35+ /L 98RON is starting to make me feel a little uncomfortable... just looking at the markets and aussie dollar has copped a beating today (sell at 74.85 US at time of posting) and hurricane katrina temporarily sending oil over 70US/bbl.... $1.40/L this weekend? $1.45?? One almost stops caring after a while. Almost. :gren:

[4Vman]

Originally Posted by Steffo

Thing is.. you're supposed to run different oil with LPG anyway..

http://www.caltex.com.au/products_oil_detail.asp?id=316

Plus don't forget the higher octane rating for LPG, making it able to utilise higher compression and higher boost without knock. That's a great thing in a performance orientated engine.

I'm still of the opinion that LPG is going to become the next big thing in Australia, until we all move to hydrogen fuel cell cars...

Steffo Steffo Steffo!! such enthusiasm!!!
Can i ask a favour?! is it remotely possible you can base at least some of your opinions or arguments around PERSONAL FIRST HAND EXPERIENCE occasionally?? please?!
The "Cut n paste" and "mag quote" stuff is interesting but you didnt experience this stuff yourself, someone else might have but it hardly helps to give solid basis for a position when you take third hand info and recite it like you experienced it yourself.

Give us some meat with our vegies mate!!! :

[chevypower]

i will say it again, if everybody converted to LPG (meaning nobody buying ULP) say hello to nice big excise to LPG - i can only see biofuels being offered with tax benefits (assuming everybody was running it) because it would help the economy even without it being taxed.

[Sourbastard]

Originally Posted by GraveDilute

pages and pages of irrelevant sites.....

Much like your post.

The largest issue with Propane or LPG, is delivery, and temperature. Vapourization at high daytime temperatures making the mixture Lean.
Freezing of various LPG components in cold climates making the bloody thing not even run. Try operating in minus temperatures sometime on LPG. Best of luck.

Keep in mind higher compression for pure LPG to draw more power also creates more heat upon combustion! More heat, higher coolant temperatures and the knock on effects from that in warm climates.

Liquid injection has issues with things like pressure levels from the in tank fuel pump(required to add extra pressure to power injectors)and the requirements for using surprlus fuel to purge vapour slurry from the fuel lines, these return absorbed heat to the tank, this can possibly increase the tank pressure to a level where you cant refill the bugger properly. The life of the LPG injectors arent very long either, they operate under high pressure and are very intricate.

The more complex the system, the more prone to failure it is.

Google is not the only source of information in this world. Go read a book.

[Steffo]

Originally Posted by 4.9 EF Futura

Inconsistency. Have a forced induction setup obviously requires quite a specific tune. How is this possible when the mix of propane to butane is not regulated? Without a complex tuning solution how does one account for varying octane ratings??

That's a very good point, but IMO, very easy to work around, especially with the LPG injection systems that are becoming more available, and generally on any vehicle with an engine management system.

LPG varies from 105 to 120 RON, depending on butane contents %. The worst LPG gets down to 102-103 RON. Now, putting a fuel rated at say.. 91 RON.. in a vehicle tuned for.. 98 RON.. will cause detonation etc, which is not good. Put putting 98 RON fuel in a vehicle tuned for 91 RON does no harm.

So, when tuning a performance orientated engine (s/charged, t/charged etc etc), I'd fill it up with a tank of LPG from BP (they're one of the worst.. 50% butane).. and tune it to suit that. So when you get LPG that's got less butane in it.. nothing bad will happen.. as the characteristics of the fuels are much the same, the butane is simply cheaper, but vastly reduces the octane rating of the fuel, ie: its easier to ignite.

Originally Posted by 4.9 EF Futura

Boot space. Every now and then I like to pack up the picnic table, grab a few chairs and an esky and head out with the mates and a couple of lady friends for a day at the beach/races/whatever... now without removing the petrol tank (and therefore increasing the cost and payback period again) I can expect to lose 30% of that boot space.

Also a very fair comment. Although, you can install the gas bottle yourself legally, so if you are capable of doing such work, you minimise cost by installing the bottle yourself, removing the tank yourself etc. If you're unable to do it, it does get a tad more expensive. Personally, I wouldn't mind sacrificing the boot space, but then, that varies from person to person, and vehicle to vehicle.

Originally Posted by 4.9 EF Futura

I cannot count on two hands the number of people that have consistent problems which can be attributed to the LPG setup.

Everyone I know who has made the switch to LPG loves it, and the people who have problems, I find, tend to have gone to a dodgy mechanic who has installed and tuned the setup poorly. No fault of the system or fuel at all, that's human fault. Although I can see your point about people having problems with something being a deterrant.. but may I ask.. shouldn't that deter one from petrol too, as people have problems with petrol cars just as much?

Some excellent points, has to be one of the most well constructed posts I've ever seen on exactly why one chooses not to use LPG.

[Steffo]

Originally Posted by 4Vman

Steffo Steffo Steffo!! such enthusiasm!!!
Can i ask a favour?! is it remotely possible you can base at least some of your opinions or arguments around PERSONAL FIRST HAND EXPERIENCE occasionally?? please?!
The "Cut n paste" and "mag quote" stuff is interesting but you didnt experience this stuff yourself, someone else might have but it hardly helps to give solid basis for a position when you take third hand info and recite it like you experienced it yourself.

Give us some meat with our vegies mate!!! :

I see how LPG vehicles run all the time, my dad drives them 12 hours a day for a living. That's as close to first hand I can give you until I have the funds to convert my own car to LPG, which will happen once I'm able to save up a grand to do it.

[pandaman]

Ok, hows this for personal experience. I learned to drive on an XC falcon on straight LPG, thing ran like a dog but did so long before it was converted to LPG and ran on said LPG system with minimal serious problems for over 100,000 km before finally blowing a head gasket and being retired.

I currently drive an XE falcon on straight gas, runs much better than the XC (thank god for small miracles), i have had no major mechanical problems with it (other than those caused by a kangaroo which would appear to having nothing to do with my choice of fuel) only minor problems with ancillaries.

My father drives an AUII ute on straight gas, this absolutely slaughters both the old X-flows in terms of performance and has had no problems with relation to the fuel system or valvetrain which people keep telling me is the first thing to go in an LPG fired vehicle.

However, all of the above vehicles serioulsy chew(ed) the juice. Between 15-20 litres/100k's mixed driving. So yeah pretty dodgy economy, but within the realms of reason for the extra consumption for LPG. They have also all had minor problems with the cooling system, leaking hoses, coupla welch plugs and a head gasket between them. Whether this has anything to do with the LPG I don't know.

What I do know is that it aint this horrible dodgy fuel thats gonna seriously damage the engine. It also isn't the be all and end all of automotive brilliance. It is a compromise and one that has worked quite well for me and my family.

[Pilch]

Originally Posted by chevypower

i will say it again, if everybody converted to LPG (meaning nobody buying ULP) say hello to nice big excise to LPG - i can only see biofuels being offered with tax benefits (assuming everybody was running it) because it would help the economy even without it being taxed.

Which is why I'm happy to sit back and watch all the poor fools continue to drive around on $1.30+ fuel while I pay $0.46 :

Originally Posted by Steffo

LPG varies from 105 to 120 RON, depending on butane contents %. The worst LPG gets down to 102-103 RON. Now, putting a fuel rated at say.. 91 RON.. in a vehicle tuned for.. 98 RON.. will cause detonation etc, which is not good. Put putting 98 RON fuel in a vehicle tuned for 91 RON does no harm.

So, when tuning a performance orientated engine (s/charged, t/charged etc etc), I'd fill it up with a tank of LPG from BP (they're one of the worst.. 50% butane).. and tune it to suit that. So when you get LPG that's got less butane in it.. nothing bad will happen.. as the characteristics of the fuels are much the same, the butane is simply cheaper, but vastly reduces the octane rating of the fuel, ie: its easier to ignite.

Well said!

The same principle applies to either fuel for octanes and the appropriate tuning, just the octane levels for petrol are more readily available to the uneducated motorist so there is less risk of detonation, etc. To elaborate on that eg. Petrol - Unleaded = 91, Premium = 95, Ultimate premium = 98.
LPG - BP = 102, Shell =106 Mobil= 108 *these are made up figures and only included for demonstration purposes*


For both fuels to be truly compared on their merits for performance and economy head to head, I feel that you would have to take two identical cars. Lets say two XD's with 4 speed manuals and 4.1 crossflow 6's, and build them from scratch.... and from "scratch" I mean all you'd have to start with is a shell and related components less fuel tanks of any description, and a bare engine block. Limit the amount of $'s that can be spent on development and see which performs best at the end!!!!!

I truly could not pick a winner. I doubt anyone else here can conclusively pick a winner either........

[pandaman]

Originally Posted by chevypower

i will say it again, if everybody converted to LPG (meaning nobody buying ULP) say hello to nice big excise to LPG - i can only see biofuels being offered with tax benefits (assuming everybody was running it) because it would help the economy even without it being taxed.

Nice big excise on LPG already on the way. The politicians seem to be planning for the decline of petrol usage and an uptake in fuels for which there is currently less demand. As for the biofuels, there is no excise break on ethanol mixes at the moment is there? Maybe not quite what you meant by biofuels but it's the closest mass scale thing i can think of at the moment.

[GraveDilute]

Originally Posted by sourbastard

Much like your post.

Sorry but ad hominem arguments don't do much for me. I did find the rest of the post interesting though

Point being that if LPG is such a poor fuel solution then why isn't the information readily available? If the information is only available in highly technical books and manuals then there is little surprise that the general public is cowed into believing that LPG is a poor fuel by those who can effectively speak the techno-bable. I am trying to be more informed, but don't intend to change my knowledge base from linguistics, finance, and economics to mechanical engineering in order to do so.

The information available in the public domain is not so dried and cut.

As posts have shown, LPG will not work for all people, in this regard petrol may be the "ultimate fuel". However, just because it is the most common fuel does not make it the best. Neither am I advocating that LPG is something which should be forced on all.

[johnydep]

Originally Posted by Black XR6

Ok, will those on the con side of this debate actually start posting some hard information that has actually been researched beyond heresay and questionable personal experience?
.......

You don't need to get agro just because some people disagree with your opinion of LPG.

Most of the pro information about LPG is from the LPG industry & enviromental lobby, so you can't really say it's unbiased.

Ford offer a LPG engine which includes enhancements to take advantage of LPG's higher octane, etc. But they have also changed some parts for durability, such as the exhaust valves & seats.
Will Ford honour the engine warranty on a BA petrol vehicle converted to LPG?
And will that engine have the same valve/seat life of the purpose built LPG engine?
Same goes with Toyota.
Then there is the oil recommendations; Ford & Holden petrol - 10w30. LPG - 15w40

For people mentioning Taxi's doing 600,000km, you can not compare an engine that is running 16 - 24 hours a day to an engine that is run 15 - 90 minutes twice a day. Stop starting cold mechanical parts always die first.

And what is the percentage of LPG to Petrol engines? This will have some bearing on why some of you do not hear too many negatives for LPG fueled vehicles.

LPG has got its benefits, but it is no industry saver.

Petrol will be the dominant fuel for a long time to come, and we will see new technology to improve petrol mileage; such as lean burn technology.

[Racecraft]

OK long post,

I have 26 cars, all 26 are dual fuel. The cars are dual fuel for one reason and one reason only. To avoid tow trucks. All my LPG set-ups start on petrol and flick over to LPG. Doing this minimises drying of the pump and injectors. It keeps them in a working state so if need arises the car can be run on ULP.

There is no doubt LPG is cheaper, I had all my AU2's running only on ULP for 12 months, the bowser price was $1 for ULP vs $45c for LPG at that time and we figured with LPG being nearly half the pump price of petrol we would give it 12 months for a comparsion.

In that twleve months:-
Maintainence:-
I spent less on ignition leads, but had to replace fuel pumps, filters and shedule an injector clean every 2nd service (20 000klms) to maintain a reasonable fuel economy.
Reliabilty:-
The cars were much of a muchness than when on only dedicated LPG. When an ULP car has issues (fuel supply for eg), it is usually terminal and needs a tow home :( , no different to a cooling issue causing a frozen convertor.

All the AU's and newer have the 'shutdown' feature in the EEC so as a car that has water loss or overheating issues will limp around thus not harming the engine. That feature in itself is a huge bonus for LPG cars that are more prone to cooling issues due to the extra plumbing to convert the LPG.
The days of the E series springing a leak and needing a headgasket were fixed by Ford with the new features in the EEC..

Now the issues of long term relability are as jonnydep said, that taxis have a huge advantage that cannot be comparitable to even a high mileage private car. But in 12 months (approx 140 00 klms) of just running ULP four of my AU engines died.. Not to the point of being undriveable but there were issues with oil comsumption and blue smoke. Those engines were thrown away in favour for low klm engines when we converted to the fleet to dual fuel.. I have never had to replace a LPG engine after 140k...

I can comment that ex cabs that don't do the 'hot' kays of a working taxi will power on indefinately, drivers that buy the retired cars have put 300000 more kays on an engine that has already done 600k. ULP engines would have been rebuilt or exchanged once if not twice or more by then.

For me, in my line of work there is only one winner, to the point where my twin turbo EL is running straight LPG as I am familiar enough with the pros and cons to not be scared off but like everything I guess, LPG is more suited to certain applications and specific models. A commodore for example will not like gas, the design just refuses to help combust the LPG.

The days where LPg was for taxis and high milage cars only is coming to an end.. With the pump price, emssion laws and the parameters on std ecus hindering performance it is swinging a whole new market to gas.

[XplosiveR6]

i will buy an LPG powered vehicle when car manufacturers start producing Electronic fuel injected LPG streight gas systems on their cars, taking off a perfectly good petrol fuel injection system , and throwing on a gas carbie seems a bit backwards to me

[Black XR6]

Originally Posted by johnydep

You don't need to get agro just because some people disagree with your opinion of LPG.

Most of the pro information about LPG is from the LPG industry & enviromental lobby, so you can't really say it's unbiased.

Ford offer a LPG engine which includes enhancements to take advantage of LPG's higher octane, etc. But they have also changed some parts for durability, such as the exhaust valves & seats.
Will Ford honour the engine warranty on a BA petrol vehicle converted to LPG?
And will that engine have the same valve/seat life of the purpose built LPG engine?
Same goes with Toyota.
Then there is the oil recommendations; Ford & Holden petrol - 10w30. LPG - 15w40

For people mentioning Taxi's doing 600,000km, you can not compare an engine that is running 16 - 24 hours a day to an engine that is run 15 - 90 minutes twice a day. Stop starting cold mechanical parts always die first.

And what is the percentage of LPG to Petrol engines? This will have some bearing on why some of you do not hear too many negatives for LPG fueled vehicles.

LPG has got its benefits, but it is no industry saver.

Petrol will be the dominant fuel for a long time to come, and we will see new technology to improve petrol mileage; such as lean burn technology.

Mate, that wasnt agro in the slightest. This is a debate after all and nothing furthers a debate one way or another than cold hard facts. Since the con side of the debate in both threads have failed to post one shread of credible information from a book or research performed I am dubious. I did actually search for both good and bad info on lpg and could only find good. If LPG was so bad there would be tech articles and website pages dedicated to this fact. But I couldnt find any.

Alot of whats said in debates and on public forums is just someone having their say not necessarily with any first hand knowledge or researched info. I can accept people have differing opinions to myself, not everyone can be correct after all :voldar02:.

[ltd]

LPG technology already has huge dollars being spent on research, as it is seen to be the fastest solution to offset the ever increasing price of crude oil. Somebody here made mention of high engine temperatures, loss of power and reduced engine life; well the solution to those problems has already been developed and is currently under test now.
I know this sounds like BS but Ford, Holden and Toyota are investing megabucks in the solution to the Petrol/LPG option at this very moment - as ethanol is too expensive, hydrogen is too expensive and electricity dependant to produce, and bio fuel companies are nowhere near the size to match the needed manufacturing capacity to sustain the market.

Without revealing any sources, I would like to remind others that in 1997, Ford developed a 230KW supercharged 6 cylinder engine that ran on LPG, based on the 4 Litre 6 available in the EL Falcon. To give a clue as to the tecnology being developed away, this test engine ford had did not suffer the usual problems associated with LPG, especially in the areas of premature fatigue on valves and valve seats. Back then petrol was in the mid 70cpl and occasionally dipping into the 80cpl range.
LPG back then was not required as much as it is today, because there was only about 30cpl difference. Today, with over 80cpl difference or 300% price premium for petrol, Australian car makers are in a race to develop alternative, price friendly vehicles.

The big 3 manufacturers in Oz have had assurances and it is general public knowledge that excise will not be introduced on LPG until December 2011; and even then it will be 2.5c indexed quarterly, capped at 12 cents. As such, failure to develop the technology can potentially result in one manufacturer getting the entire upper hand on the other. For example, if all Fords came with an LPG option that had the same or more power than their petrol counterpart, then Holden would potentially go to the wall, as nobody in their right mind would pay 150cpl as opposed to 46cpl. Already the big 3 have commenced durability testing in laboratories.
In the next 1-2 years we will start to see an abundance of LPG fuelled cars available.

[Sourbastard]

Originally Posted by GraveDilute

Sorry but ad hominem arguments don't do much for me. I did find the rest of the post interesting though

LOL wasnt so much an ad hominem attack as a statement of the bleeding obvious. If you post "we aint found $hit" you have contributed nothing. Hence worthless post.

Point being that if LPG is such a poor fuel solution then why isn't the information readily available? If the information is only available in highly technical books and manuals then there is little surprise that the general public is cowed into believing that LPG is a poor fuel by those who can effectively speak the techno-bable. I am trying to be more informed, but don't intend to change my knowledge base from linguistics, finance, and economics to mechanical engineering in order to do so.

You hardly need to change your "knowledge base". Most of it is simple physics and some chemistry that we would have undertaken in High School.

And LPG is NOT a poor fuel. It is just a type of fuel. Just like any other fuel. And as I said before it has its Pro's and Con's just like any other fuel type. If you want financial Economy(At the current price anyway), LPG is a good choice in a mild climate. If you want power or live in an extreme climate, there are many different options, petrol being just one.

The information available in the public domain is not so dried and cut.

Try this: http://www.eng-tips.com/threadminder.cfm?pid=71
Theres heaps of information out there, just have to do some serious research, it isnt going to come to you.

As posts have shown, LPG will not work for all people, in this regard petrol may be the "ultimate fuel". However, just because it is the most common fuel does not make it the best. Neither am I advocating that LPG is something which should be forced on all.

Petrol is not the ultimate fuel. To my knowledge, there is no ultimate fuel. Because everyone is looking for something different from their vehicle.

The simple answer to this entire thread is, Neither fuel is better then the other as they both accomplish different things in different ways.

[Sprint347]

petrol powers cars, lpg powers bbq's... simple