What Are The Downsides Of Using Lpg Vs Benzene?

[steelepulse]

Besides availability and the tank taking up room in the boot, what other downsides are there in using LPG? Less mileage on the engine? Less power even though higher octane?

[MikeyIdea]

Yes to all, and also that engines have a tendency to be difficult to start when they are hot

[chav]

The tank is heavy so quite often have problems with the rear ride hight, your shocks and springs will suffer over time. Normally they will change to gas shocks and put spacers under the springs. (!Nice!)

If you do decide to use gas make sure you run the car on bezine regualarly. i have come across many a car with stale fuel in the tank and dead injectors making them hard to start and rough running (if at all)

Some conversions just pipe directly into the air intake leading to problems with the airflow meter or air mass meter.

Best system allthough pricier is the injection type.

Always make sure you get it fitted by a certified engineer who can certify it himself (not buy a cert for 400 baht from an Adjarn who hasnt seen the car)

Finaly when you have all this done you need to have your registration book changed to show that it has been converted to gas.

Hope this helps.

Gavin

[stingray]

I see so many umprofessional LPG instalations, that i'm suprised thet not more explosions happen overhere. Officials always forget: It's not only the Gastank who have to be save! A save instalaton is very important as well, but when i see gas pipes hanging loose arround rear wheels or fittet 2 milimeter ,next to the exhoust collector, i'm really wonder. Had several cars with LPG installations. Mosthly starting problems in the morning, or car stalls when automatic change over from Benzine to LPG, bad fuel pumps, rusty thanks, wich resulting in dead fuel pumps, because peaple runn ing the fuel out to the last drop until it's compleately emty, so i could go on and on. More problems than not.

But i think a good system, imported from Italy, will do fine, but it cost about 40 to 60'k, depend on how many cylinder your engine have. At least in Europe it works fine. But then again to get your (invested) money back you have to stick with that same car for at least a couple years.

[katabeachbum]

Gas Vs Petrol, only a few weeks ago.

steelpulse, if its a beemer, running LPG or even worse CNG, valves and top are major probs even if gas injection. lubrication and temperature, so adding 2 stroke lube doesnt help on beemers

[BSJ]

The newer injected systems are very very good. But can you get them in LOS?

Check this site for information

Prins Autogassystemen BV

VSI-LPG system

VSI is an abbreviation for "Vapour Sequential Injection". The VSI-LPG system is the most advanced LPG system available on the market. With the VSI-LPG system there is no difference between driving on petrol or on LPG.

The VSI-LPG system is developed in close cooperation with Keihin Corp. of Japan, one of the world’s leading injector manufacturers and a name that stands for OEM quality and reliability.

The VSI-LPG system is fully integrated by way of a "master - slave" method with the vehicle ECU, making it (E)OBD compatible, therefore signal emulation is not required.

The key components of the system are all of OEM quality and specially designed for LPG applications. All components comply with the strictest regulations and certifications. The installation of the components is very easy due to the compact design of the components.

The specially dedicated diagnostic software is unique and enables fine tuning the VSI-LPG system for optimal performance and emission reduction.

For the storage of the LPG there are different tank options available.

[seedy]

For what it costs, to what you will save, balanced with the loss of power, added complexity. In my opinion a total waste. People have been trying for years to 'improve' cars by not using gasoline. Has not happened yet, and I doubt that it ever will. Gas for light duty, diesel for heavy duty. Why try to reinvent the wheel.

[WarpSpeed]

For what it costs, to what you will save, balanced with the loss of power, added complexity. In my opinion a total waste. People have been trying for years to 'improve' cars by not using gasoline. Has not happened yet, and I doubt that it ever will. Gas for light duty, diesel for heavy duty. Why try to reinvent the wheel.

Because the wheel is wearing out and besides they've been successfully reinventing them for decades now so that analogy is outdated.. The loss of power is virtually undetectable and very easy to deal with, since I professionally tuned my car myself and replaced a badly needed timing belt my car runs perfectly on both fuels without any detonation or over heating and only a minimal difference in throttle response between Petrol and LP that the average driver would never notice.

No problem with starting my car at any point either hot or cold on either fuel but choose to start on petrol unless warm actually then LP is OK.

The big difference is when I pull up to the high octane pump and can only get just under half a tank of gasoline for 600b where as I get a full tank of LP about 50L give or take a L or 2 for 530b and a ton more mileage for the cost.. Not to mention the 2 bottled waters they give me for free for when we're broken down waiting for a tow truck ...

But seriously the trick for me is to start the car on petrol until it warms up as is recommended mostly for efficiency but also to lube it up well and give it breaks while sitting in traffic by occasionally running on petrol to lube and cool the valves and also during long trips for short periods and when slowing to my destination. I also didn't purchase my system it came with the car so for me it was a bonus I didn't pay out of pocket for, making it well worth the cost, so maybe that's another trick is to let someone else bare the cost of installation and you reap the benefits..

But from an actual owner/operator who fully understands the system I have and not just an old school motor head who has not really experienced one personally, I rate it very well and I'm not lucky enough to have a direct injection system which I'm certain I would enjoy that much more..

[jaideeguy]

Are the few new factory installed [and waranteed] systems any better than the retrofit systems??

And what options are there in a station wagon type behicle?? Have seen factory installed chev optra that look decent. What other's out there??

[katabeachbum]

For what it costs, to what you will save, balanced with the loss of power, added complexity. In my opinion a total waste. People have been trying for years to 'improve' cars by not using gasoline. Has not happened yet, and I doubt that it ever will. Gas for light duty, diesel for heavy duty. Why try to reinvent the wheel.

Because the wheel is wearing out and besides they've been successfully reinventing them for decades now so that analogy is outdated.. The loss of power is virtually undetectable and very easy to deal with, since I professionally tuned my car myself and replaced a badly needed timing belt my car runs perfectly on both fuels without any detonation or over heating and only a minimal difference in throttle response between Petrol and LP that the average driver would never notice.

No problem with starting my car at any point either hot or cold on either fuel but choose to start on petrol unless warm actually then LP is OK.

The big difference is when I pull up to the high octane pump and can only get just under half a tank of gasoline for 600b where as I get a full tank of LP about 50L give or take a L or 2 for 530b and a ton more mileage for the cost.. Not to mention the 2 bottled waters they give me for free for when we're broken down waiting for a tow truck ...

But seriously the trick for me is to start the car on petrol until it warms up as is recommended mostly for efficiency but also to lube it up well and give it breaks while sitting in traffic by occasionally running on petrol to lube and cool the valves and also during long trips for short periods and when slowing to my destination. I also didn't purchase my system it came with the car so for me it was a bonus I didn't pay out of pocket for, making it well worth the cost, so maybe that's another trick is to let someone else bare the cost of installation and you reap the benefits..

But from an actual owner/operator who fully understands the system I have and not just an old school motor head who has not really experienced one personally, I rate it very well and I'm not lucky enough to have a direct injection system which I'm certain I would enjoy that much more..

Just read an ad for Mitsu Lancer. It comes new with 5year/150k km warranty on petrol, but warranty reduced to 3 year/100k km if running CNG or LPG.

[jaideeguy]

Just read an ad for Mitsu Lancer. It comes new with 5year/150k km warranty on petrol, but warranty reduced to 3 year/100k km if running CNG or LPG.

Wonder why warantee is less?? And what about performance??

and do the new factory instaled rigs operate on both LPG and CNG???

[aussiebebe]

The downside of using LPG is that the engines were never designed to use it originally, hence the reduced warranties.

The up side of factory-fitted systems is that the filling cap is in the correct place and you get a warranty.

The principle disadvantage of all the factory fitted NGV vehicles is that they too are retrofitted and partially modified. If they were really 'designed' to use gas, the car would have been designed so that the tank was fitted without compromising space. Possibly under the rear seats, under the chassis, or donut shaped into the spare wheel well. But no. They just put the tank in the trunk (boot) like a retrofit would. Look at the Proton Persona, Toyota Altis (taxi) Chevy Optra, Colorado, or Optra estate. Especially that Optra estate - why buy an estate if you can't use the trunk (boot)? Madness.

Only one vehicle has been genuinely designed for gas that I know of - the Tata CNG pick-up, the bed lifts up, the tanks are under.

[katabeachbum]

Just read an ad for Mitsu Lancer. It comes new with 5year/150k km warranty on petrol, but warranty reduced to 3 year/100k km if running CNG or LPG.

Wonder why warantee is less?? And what about performance??

and do the new factory instaled rigs operate on both LPG and CNG???

Toyota Altis has the same 3 year/100k km warranty on petrol and CNG, but for CNG they have modified the engine.

LPG and even worse CNG has much higher combustion temperature than petrol, thus engine damages. There are engines who can handle this for 3-400k km, like most 2 valve V8 and V10 larger than 5000cc, Volvo 2,5 inline 5, VW 2,5 inline 5, and older Volvo 2,3 4 pots.

A CNG system is very different from a LPG system, so none of them can handle both fuels. Use CNG in a LPG tank and it blows up.

CNG peformance is usually sluggish. Read a test in bkk post Hyundai Sonata factory fitted CNG, stopped frequently on idle. LPG in a 4 pot less than 2500cc performance reduced 10-30% pending on engine and LPG system.

[VocalNeal]

Does anyone know if factory CNG vehicles come with those"autolube"units used by Bangkok taxi drivers?

[katabeachbum]

<BR>Does anyone know if factory CNG vehicles come with those<A class=bbc_url title="External link" href="http://www.flashlube.com/en/valvesaverkit/index.html" rel="nofollow external">"autolube"</A>units used by Bangkok taxi drivers?<BR>

autolube meaning 2 stroke oil injection. cant be factory installed since emission would be illegal. besides lubing is not the main reason for manufactorer to modify engines or reducing warranty, heat issues are. burned valves, head and pistons being most common problem

[WarpSpeed]

For what it costs, to what you will save, balanced with the loss of power, added complexity. In my opinion a total waste. People have been trying for years to 'improve' cars by not using gasoline. Has not happened yet, and I doubt that it ever will. Gas for light duty, diesel for heavy duty. Why try to reinvent the wheel.

Because the wheel is wearing out and besides they've been successfully reinventing them for decades now so that analogy is outdated.. The loss of power is virtually undetectable and very easy to deal with, since I professionally tuned my car myself and replaced a badly needed timing belt my car runs perfectly on both fuels without any detonation or over heating and only a minimal difference in throttle response between Petrol and LP that the average driver would never notice.

No problem with starting my car at any point either hot or cold on either fuel but choose to start on petrol unless warm actually then LP is OK.

The big difference is when I pull up to the high octane pump and can only get just under half a tank of gasoline for 600b where as I get a full tank of LP about 50L give or take a L or 2 for 530b and a ton more mileage for the cost.. Not to mention the 2 bottled waters they give me for free for when we're broken down waiting for a tow truck ...

But seriously the trick for me is to start the car on petrol until it warms up as is recommended mostly for efficiency but also to lube it up well and give it breaks while sitting in traffic by occasionally running on petrol to lube and cool the valves and also during long trips for short periods and when slowing to my destination. I also didn't purchase my system it came with the car so for me it was a bonus I didn't pay out of pocket for, making it well worth the cost, so maybe that's another trick is to let someone else bare the cost of installation and you reap the benefits..

But from an actual owner/operator who fully understands the system I have and not just an old school motor head who has not really experienced one personally, I rate it very well and I'm not lucky enough to have a direct injection system which I'm certain I would enjoy that much more..

Just read an ad for Mitsu Lancer. It comes new with 5year/150k km warranty on petrol, but warranty reduced to 3 year/100k km if running CNG or LPG.

And you'd have to read back through this thread or the multitude of other threads on this topic to see where I mentioned that I'd be more adverse to installing one on a new car wouldn't you?? As I don't believe you'd get your money out of it otherwise since the newer cars can run on cheaper gasohol blends without significantly poor performance... The only thing I see about the warranty is another way for the manufacturer to sell you something that allows them to get out of their warranty obligations at an earlier point... If you have an older car though that requires something like 95 benzine to run well which I just purchased yesterday at 42 per litre then it more then makes up for it since I filled my LP tank with about 40L for 450b yesterday and only barely moved my gas gauge past 1/4 tank for 95 petrol with 600b and only 15 litres...

At that return I'll take my chances and do a valve job years from now or just sell the car long before that happens, though I'm confident the way it runs and the way I take care of it it I won't have such issues while I own it... But for those of you who are clueless definitely avoid LP at all costs it really requires a knowledgeable owner to operate it properly which definitely excludes the larger masses here, so not unexpected that most here would be opposing it and not recognize the potential benefits..

[INTJ]

"most here would be opposing it and not recognize the potential benefit"

That attitude surprises me too, as since 2005 I have personally done over 200,000km on LPG and my mrs probably another 100,000, never had a single problem. I always start up on 91 and switch over to gas after a minute or so. Mileage mainly done in Toyota JZ and UZ series engines.

Perhaps some boffin could do a calculation on approx how much has been saved, I'll bet its a lot

My neighbour has just bought a new Altis with factory CNG......I was amazed to still see the huge tank filling the boot, I would have thought that Toyota would have found a way to hide that monstrosity like Tata trucks and give the thing some boot space, but no...........

Today I've just started a 1JZ-VVTi swap into a pickup, that will be converted to LPG with the tank mounted underneath, if the size of the original fuel tank is reduced it should even be possible to keep the original spare wheel.

So anyone saying LPG is bad, dangerous, damages your engine - perhaps in some circumstances (known incompatible engines like BMW, botched installations etc.) but my experience is quite the opposite. LPG liter 12 baht, 91 liter 36 baht - no brainer. Still feels good filling up for 600 baht after all these years.

Cheers

[jaideeguy]

A bit off topic, but I've been thinking of getting a backup generator, 4 or 5kw and now wondering if there are lpg or cng models??

[WarpSpeed]

Because the wheel is wearing out and besides they've been successfully reinventing them for decades now so that analogy is outdated.. The loss of power is virtually undetectable and very easy to deal with, since I professionally tuned my car myself and replaced a badly needed timing belt my car runs perfectly on both fuels without any detonation or over heating and only a minimal difference in throttle response between Petrol and LP that the average driver would never notice.

No problem with starting my car at any point either hot or cold on either fuel but choose to start on petrol unless warm actually then LP is OK.

The big difference is when I pull up to the high octane pump and can only get just under half a tank of gasoline for 600b where as I get a full tank of LP about 50L give or take a L or 2 for 530b and a ton more mileage for the cost.. Not to mention the 2 bottled waters they give me for free for when we're broken down waiting for a tow truck ...

But seriously the trick for me is to start the car on petrol until it warms up as is recommended mostly for efficiency but also to lube it up well and give it breaks while sitting in traffic by occasionally running on petrol to lube and cool the valves and also during long trips for short periods and when slowing to my destination. I also didn't purchase my system it came with the car so for me it was a bonus I didn't pay out of pocket for, making it well worth the cost, so maybe that's another trick is to let someone else bare the cost of installation and you reap the benefits..

But from an actual owner/operator who fully understands the system I have and not just an old school motor head who has not really experienced one personally, I rate it very well and I'm not lucky enough to have a direct injection system which I'm certain I would enjoy that much more..

Just read an ad for Mitsu Lancer. It comes new with 5year/150k km warranty on petrol, but warranty reduced to 3 year/100k km if running CNG or LPG.

And you'd have to read back through this thread or the multitude of other threads on this topic to see where I mentioned that I'd be more adverse to installing one on a new car wouldn't you?? As I don't believe you'd get your money out of it otherwise since the newer cars can run on cheaper gasohol blends without significantly poor performance... The only thing I see about the warranty is another way for the manufacturer to sell you something that allows them to get out of their warranty obligations at an earlier point... If you have an older car though that requires something like 95 benzine to run well which I just purchased yesterday at 42 per litre then it more then makes up for it since I filled my LP tank with about 40L for 450b yesterday and only barely moved my gas gauge past 1/4 tank for 95 petrol with 600b and only 15 litres...

At that return I'll take my chances and do a valve job years from now or just sell the car long before that happens, though I'm confident the way it runs and the way I take care of it it I won't have such issues while I own it... But for those of you who are clueless definitely avoid LP at all costs it really requires a knowledgeable owner to operate it properly which definitely excludes the larger masses here, so not unexpected that most here would be opposing it and not recognize the potential benefits..

Nobody, but nobody knows what damage is being caused using LPG unless you strip down the engine to see whats going on or wait for a failure. You can service it, polish it, change the oil every weekend but you still don't know whats going on, unless a plug tip disappears or you get a miss with valve probs.

Well regular checking of plugs and reading them is one way to have a good indication of what's going on internally but while I agree with you, what I would like to know is how this doesn't apply to any engine and fuel combination?? That is to say that no one has any idea of any internal damage being caused until the very same symptoms and diagnostics are applied in every case..

[INTJ]

I think I better convert back to gasoline, it seems I might need a 5000 baht cylinder head every 400,000km

[katabeachbum]

"most here would be opposing it and not recognize the potential benefit"

That attitude surprises me too, as since 2005 I have personally done over 200,000km on LPG and my mrs probably another 100,000, never had a single problem. I always start up on 91 and switch over to gas after a minute or so. Mileage mainly done in Toyota JZ and UZ series engines.

Perhaps some boffin could do a calculation on approx how much has been saved, I'll bet its a lot

My neighbour has just bought a new Altis with factory CNG......I was amazed to still see the huge tank filling the boot, I would have thought that Toyota would have found a way to hide that monstrosity like Tata trucks and give the thing some boot space, but no...........

Today I've just started a 1JZ-VVTi swap into a pickup, that will be converted to LPG with the tank mounted underneath, if the size of the original fuel tank is reduced it should even be possible to keep the original spare wheel.

So anyone saying LPG is bad, dangerous, damages your engine - perhaps in some circumstances (known incompatible engines like BMW, botched installations etc.) but my experience is quite the opposite. LPG liter 12 baht, 91 liter 36 baht - no brainer. Still feels good filling up for 600 baht after all these years.

Cheers

Most car makers say LPG and CNG damage their engines, thus modified engine when factory equipped with LPG or reduced warranties. Lucky you no problem.

My 2000 Ford Excursion 6,8L V10 has done 350k km on LPG by now without engine probs. It doesnt indicate thats the norm for any 4 pot.

[INTJ]

Bangkok taxis are all 4 pots running LPG for a million KM.....how often do you see a taxi broken down considering how many are on the road ?

Any Toyota engine will be fine on LPG for huge mileage, other makes I cannot comment as I have no long term experience.

Cheers

[thaicbr]

One of the reasons that the manufacterers dont do tidier installs is simple. The government regulations do not allow any tank other than a cylindrical tank blah, blah, blah mucho tech babble.

[katabeachbum]

Bangkok taxis are all 4 pots running LPG for a million KM.....how often do you see a taxi broken down considering how many are on the road ?

Any Toyota engine will be fine on LPG for huge mileage, other makes I cannot comment as I have no long term experience.

Cheers

Read up on another LPG thread here.

Most Toyota 4 pot with simple LPG system dont last 100k km.

BKK taxis ad 2 stroke lube to survive, and still they rebuild head and valves every second year or every year.

Stll good profit running LPG.

Now LPG installation is illegal to do in bkk taxi, CNG is the thing, and Toyota has been kind enough to improve their 4 pot to handle this.

[seedy]

As quoted above by Transam - my point exactly.

Design an engine from the start to run LPG - or CNG - and I will be convinced. Try to redesign a gasoline engine to use a different fuel is just asking for trouble, in my opinion.

Your opinion may vary.

As an 'Old Skool Motor Head' as I have been described, I have seen many attempts to "improve" things. Most do not work.

My racing experience has shown that if you want to try, be prepared for regular teardowns - to check if your 'improvements' work.

But - Up To You

[WarpSpeed]

Actually there's an easier way to do it then that and it's what I'm going to do, as a racer you should know about it too. I'm just simply going to install a stoichiometric meter to monitor the difference in temps and how the engine is operating in all conditions without guessing... The exhaust gas temps coupled with reading the plugs will tell the entire story, enough said..

[WarpSpeed]

As an 'Old Skool Motor Head' as I have been described, I have seen many attempts to "improve" things. Most do not work.

So you're trying to sell the fact that a 1.8 litre engine of today has no power or performance improvements over yesterday and so on. It is always thought that no more can be gotten out of an engine then has already been done and yet the same size engines of today are mostly 100% more powerful, durable and efficient over yesteryear. This suggestion illustrates your thinking is "old school" and why you earned that label if it was directed towards you that is, I think it was more a general reference myself that you've personally adopted...All closed minded and rigid, in the box thinking is considered "old school"...

Refinement is the way forward in all cases and only comes from experience and trial and error, look at Toyota for example in spite of all of their resources and experience they still managed another recall for engines that stall unexpectedly. Another example is if the time comes for me to rebuild and desire to improve this engines durability to withstand higher LPG temps for longer periods of time as I might not feel it is currently sufficient (though that hasn't been proven yet) the technology and parts already exist as aftermarket bolt ons to improve the durability and if I deem it necessary to improve on the wheel I will, simple as that..

In the mean time I enjoy significant savings on fuel and until that fateful day I'll happily save my money using LP (plenty of savings) and not worrying about it anymore then I do getting a flat tire when driving....

[katabeachbum]

Actually there's an easier way to do it then that and it's what I'm going to do, as a racer you should know about it too. I'm just simply going to install a stoichiometric meter to monitor the difference in temps and how the engine is operating in all conditions without guessing... The exhaust gas temps coupled with reading the plugs will tell the entire story, enough said..

exhaust temp is a fantastic way to read engine. and running LPG you will instantly see temp is more than double its designed for. Some engines manage, some die prematurely.

can even be identical engines, one was just more lucky during manufactoring with better quality head, valves and pistons

but for the engine manufactorer, they have to assume all engines are within tolerance, and adjust warranties for LPG and CNG users accordingly.

[WarpSpeed]

Actually there's an easier way to do it then that and it's what I'm going to do, as a racer you should know about it too. I'm just simply going to install a stoichiometric meter to monitor the difference in temps and how the engine is operating in all conditions without guessing... The exhaust gas temps coupled with reading the plugs will tell the entire story, enough said..

exhaust temp is a fantastic way to read engine. and running LPG you will instantly see temp is more than double its designed for. Some engines manage, some die prematurely.

can even be identical engines, one was just more lucky during manufactoring with better quality head, valves and pistons

but for the engine manufactorer, they have to assume all engines are within tolerance, and adjust warranties for LPG and CNG users accordingly.

Yes and I fully expect to find that difference, I agree about the CYA approach to warranties and the variation in quality of parts given the variance of parts providers that was what I mentioned earlier maybe it was this thread I don't remember but since the car is not working like a race car at optimum/maximum output 99% of the time the variance in temps should be tolerable across the board peaking and dropping but that's what I intend to find out.

We used one to tune the car and then to monitor it during the race and the sweet spot for max stoichiometric and performance was about 1450 to 1525 Degrees at the header and you began burning valves at approximately 1600 to 1700 degrees if left there for long and higher temps for valve seats and such since the material is harder and thicker generally speaking and dissipates more heat. But since a street car is seldom ever running at maximum output like we run a race car especially with seldom backing off I don't expect any seriously high temps for any significant length of time relatively speaking, the cooling effect is immediate once off the throttle and regardless of tuning with whatever fuel if the temps aren't consistently high enough they will not do any internal damage..

Using that data acquired and applying it in this instance is going to be tell tale of the real facts, if it isn't exceeding those temps for lengthy periods then there is little to no real detrimental effect to be had on the average well produced engine unless the owner does not know or understand how to properly care for and operate his/her car which is where I believe much of the myth of engine abuse emanates from not the fact that it is LP exclusively but because it is still a bit of an enigma to most people and mechanics alike..

[JohnLeech]

I think that mr and mrs average driver wants to go to the shops and back, end of story. Doesn't want to know about racer tech to keep it going. Either LPG does the job no problem or keep using the stuff the manufacturer recommends for looooong engine life.

Exactly.