propane/CNG conversion

[superu]

I have been thinking of doing a conversion to my 95 legacy 2.2. It'd be nice to burn cleaner than gasoline, especially with raising fuel costs. Plus it would be cool to be able to use the car pool lane with the incintive or a cleaner-burning automobile...

 

I would like to be able to run gasoline also and I understand when doing a propane conversion you can switch and run either gasoline or propane. is the same true for CNG?

 

So I've mainly thought about propane, but recently i've thought about CNG as well.

 

Does anyone know good pros and cons of each of these and how it could be done?

 

thanx,

-mw-

[porcupine73]

These conversions seem to be popular in other countries, especially such as India. I was trying to find info on this a few years back and there didn't seem to be a lot of choices in the U.S. I would definitely be interested as well if anyone has info.

 

CNG works if you are filling at a station which already has it pressurized; otherwise you need a compressor to take your home supply of ~4inwc up to a few thousand psig in the cylinders.

 

Sometimes on eBay you will see CNG vehicles already for sale, especially certain Ford models.

[rverdoold]

Yes CNG cars can also run on gasoline and theoretical also on propane (although injectors are slightly different) I would go for propane cause there are more systems available (like here in holland) or in germany. We can even get factory propane installations which are sold under the label Legacy Ecomatic (http://www.subaru-ecomatic.de/).

 

I mean to get the right components its easier for propane than for cng.

success with the conversion.

 

My dad just drove 60k mile on propane in 2 years without any problems at all having service intervalls every 17.500 km. Note there is no loss in power or topspeed (and i know cause we have autobahn ).

[nipper]

I have been thinking of doing a conversion to my 95 legacy 2.2. It'd be nice to burn cleaner than gasoline, especially with raising fuel costs. Plus it would be cool to be able to use the car pool lane with the incintive or a cleaner-burning automobile...

 

I would like to be able to run gasoline also and I understand when doing a propane conversion you can switch and run either gasoline or propane. is the same true for CNG?

 

So I've mainly thought about propane, but recently i've thought about CNG as well.

 

Does anyone know good pros and cons of each of these and how it could be done?

 

thanx,

-mw-

 

Look at the bottom of the page for related threads.

 

nipper

[Reveeen]

I really hate to be a nay sayer but:

Alternate fuels, no matter the type, only work as long as your government chooses to play along.

In Canada, in the late 80's, early 90's, the government was all for alternate automotive fuels. They granted individuals (and companies) money for conversion (up to $1500 a unit) and gave a tax holiday on fuel purchases.

At this time I became a licensed automotive propane/natural gas "fitter".

I was also running a fleet of 5 ton International trucks.

 

The situation here (in Canada) is far different today. It is simply not economically reasonable to switch to alternate fuels today (no conversion help, no tax breaks).

 

1) A gallon of Propane produces 20% less BTUs than a gallon of gasoline

(your propane cost has to be less than 80% the same quantity cost of gasoline for it to be a "savings")

2) Propane does not work well at air temperatures of less than -15C

3) Because propane is a slower burning fuel timing adjustments must be made, adjustments that are not gasoline "friendly", dual fuel conversions end up being the worst of 2 worlds.

 

Yes, you will save on maintenance, but most garages do not want to touch a propane/natural gas conversion. There are also a whole bunch of other laws that come into play (storage of pressure vessels on ferry boats for one).

 

It is just not good here and I can't recommend it.

[cookie]

We also had propane problems here in sf. They turn into a propane refrigerator in damp conditions if not warmed quickly.

You open the hood and all you see is snow and it won't run until you warm it for several hours.

If you raise the engine's compression you can make up for the power loss.

Noboy runs it right now around here and many fleets did in the 70s because it was cost effective.

Great on foklifts though. If the price is right it's worth the hassle.

The CNG stuff we have had lately has required very high pressure and the tank size is a problem. On small busses I can't get enough range, on big one you can intall tanks on the roof to make up for it.

Right now the cleanest bus I can buy is gasoline. You can also get CNG and fit them with a trap and they are pretty clean.

[nipper]

Its easier to do if you have a carb. As you obsereved, it is really good at making ice. The fuel needs to be preheated, and depending upon the kit, may use gasoline as a starting fuel.

 

http://pugetsoundcleancities.org/pdfs/cng_lpg_conversion_facts.pdf

 

http://www.omnitekcorp.com/altfuel.htm

 

the cost really isnt worth the savings (if any).

 

nipper

[avk]

True that a carburated engine would be easier to convert properly.

With a fuel-injection type intake manifold, you don't want those long runners to be all filled up

with explosive mixture.

I understand that port-injection conversions also exist, but they are quite costly.

[johnceggleston]

the cost really isnt worth the savings (if any).

 

nipper

i heard some one on tv say, the price of gasoline in this country will always be just below the the price that makes it economical to switch. in other words why would opec or the gas companies raise the price of gas so much to send us a packing to the conversion websites??? probably not until the supply dwindles.

[nipper]

i heard some one on tv say, the price of gasoline in this country will always be just below the the price that makes it economical to switch. in other words why would opec or the gas companies raise the price of gas so much to send us a packing to the conversion websites??? probably not until the supply dwindles.

 

Thats part of the pricing game. But remeber the spot market is out of control of OPEC and EXXON. OPEC keeps trying to bring it down, for fear of what you just said.

i think the next big bubble will be energy futures, which is what banks and pension funds are investing in now. Thats why oil is about 30.00 higher then what everyone else says it actually is.

 

I will be dancing on the graves of investment houses when the artificially high oil price bubble pops.

 

nipper

[Reveeen]

During WWII in Europe fuel for vehicles was at a premium. Germany had no sources for oil, but still had to move material around, they used wood, adapting their vehicles (trucks) to use a by-product from wood burning.

 

There is a "how-to" here:

http://www.motherearthnews.com/Homesteading-and-Self-Reliance/1981-05-01/Mothers-Woodburning-Truck.aspx

 

Probably not suitable to run your Subaru car on, but something to *think* about.

 

Life is all about trade-offs, you might hire the neighbors kid to cut your lawn, simply because you don't have time to do it yourself, because you are busy making more money doing something else. I don't heat my house with wood, because the time I would spend preparing the wood, I spend making more money than heating oil costs.

[rverdoold]

I wont agree that propane doesnt work at temperatures below 15 degrees. Thats because the tank is in the car. The G3 or Euro4 LPI (liquid propane injection) looks like gasoline injection. And when you start the car it will always run on gasoline for a minute or 2 and then switches to propane. The system is built by vialle en Holland and UK.

[Reveeen]

rverdoold:

I have no doubt that such a system is far superior to the "norm" here in N America. What does it cost? Or should I say "the topic of discussion is converting a 1995 car" (maybe worth $2500?) How far would you have to drive a 13 year old car to recover the cost of conversion out of the savings? Considering gasoline today is $1.05 a liter where I live (and auto propane not far behind at $1.03 a liter) I question the ability to realize any savings, but I might add that any European system here is simply not serviceable, and would render a car equipped with such a system un-serviceable in general, as conventional mechanics won't touch it. Even conversion to the "norm" found in N America limits a converted vehicle to very few mechanics, as alternate fuel licenses are few, and far between. In many parts of N America mechanics are not licensed, once you throw flammable gas under pressure into the mix (that does require a license everywhere) it becomes very "limiting".

[rverdoold]

Well the thing here is a litre of gasoline E95 = 1.50 euro and propane is 0.50 euro (dont convert dollar euro ratio is not to good for americans).

On average an installation + installing + MOT costs 2000 to 2500 euros, fuel consumption is 8.8 l/100 km for gasoline and 11.1 l/100 km for propane. Here we say we have to drive at least 7500 km a year to be cheaper of with propane. There is more than only a price difference in tanking. Propane cars pay (for 2.5 05 OBW) 800 euros road tax while without propane its 500 euros. This is only because the propane is a modern G3 labeled system otherwise road tax would be 1500 euros which is not good for the switch KM (ratio when propane becomes cheaper).

 

With such a small difference in price you will only be doing it because its better for the environment. Plus on an fuel injected engine you need a propane injected system. Its much easier for carbarated cars then.

[cookie]

I like the idea of starting on gas as it would solve the freezing problems I had. It would be fun to do and a collectors item of sorts but financially not so great just now. Best get an old Mercedes diesel and start collecting french fry oil.

[nipper]

I like the idea of starting on gas as it would solve the freezing problems I had. It would be fun to do and a collectors item of sorts but financially not so great just now. Best get an old Mercedes diesel and start collecting french fry oil.

 

Or a vw rabbit diesel.

 

nipper

[Reveeen]

you will only be doing it because its better for the environment.

 

Reality check:

Propane is an oil by-product from the manufacture of gasoline.

You would be doing far more for the enviroment to purchase a vehicle that is the most fuel efficient, no matter the fuel, from the beginning, not the end.

 

On average an installation + installing + MOT costs 2000 to 2500 euros

 

$2845-$3560 US

[rverdoold]

you will only be doing it because its better for the environment.

 

Reality check:

Propane is an oil by-product from the manufacture of gasoline.

You would be doing far more for the enviroment to purchase a vehicle that is the most fuel efficient, no matter the fuel, from the beginning, not the end.

 

Yes you are right, but here in holland LPG is usually just flamed at the refinery. So the product is waste of making gasoline. So in fact its cleaner to run on waste than on gasoline .

I completely agree on the fact that we should change to an other source of energy. Biodiesel is an option (and really hoping the new boxer diesel will run on biodiesel). Than is the E85 (ethanol85) a real option but yet no information from subaru europe about both of these topics. The question if the diesel could run 50/50 on diesel/biodiesel was a very euuuhmm we are not sure yet answer. If subaru wants to sell the diesel in germany (most diesel country in EU) it has to be able to run biodiesel.

Of course biodiesel and E85 are steps in between to Hydrogen or pure electric but that will take at least an other 50 years.

 

On average an installation + installing + MOT costs 2000 to 2500 euros

 

$2845-$3560 US

 

Sorry about the dollar euro exhange ratio. But its nice for me to import things from there. (15 years ago it was the other way around)

[Reveeen]

Sorry about the dollar euro exchange ratio.

 

It's no matter, just doesn't make much sense converting a $2500 car, does it?

 

but here in Holland LPG is usually just flamed at the refinery.

 

It used to be that way here too, but the demand has outpaced the supply, and now the majority of propane is manufactured as such from crude oil.

 

I completely agree on the fact that we should change to an other source of energy.

 

Well, we spent 100 years getting to where we are now, I don't *think* any change will happen over night.

 

Of course biodiesel and E85 are steps in between to Hydrogen or pure electric

 

I am not convinced Hydrogen or electric are an answer. Maybe there, here the electric industry is the dirtiest industry in N America, be it acid rain from coal burning plants, or nuclear waste to be disposed of, the electricity generating industry creates more pollution than the top two other industries. I *think* it more important to utilize the resources as best as you can, rather then hope for a major change that will take decades, not years.

[rverdoold]

I am not convinced Hydrogen or electric are an answer. Maybe there, here the electric industry is the dirtiest industry in N America, be it acid rain from coal burning plants, or nuclear waste to be disposed of, the electricity generating industry creates more pollution than the top two other industries. I *think* it more important to utilize the resources as best as you can, rather then hope for a major change that will take decades, not years.

 

Everybodies says 'Reneable Energy' and i can not disagree with them but. The way it should be donei not that easy. Here the just opened an Off-shore windgenerator plant. Since we have lots of Natural Gas recourse our energy is made from that which is not the most polluting from the choices. The previous government said that by 2012 all our nuclear power plants would have been shut down but new one says at least untill 2025 they are open. At my university they designed a tidal energy station and the trails look very promising. But you are right it took 100 years to get here and it needs also time to go further.

[rverdoold]

For the interest of the thread i will make some images of the Koltec LPI installation the 05 OBW.