propane conversion

i always used impco and rego equipment

http://www.impco.ws/

http://www.regoproducts.com/

Good choice..but remember there is not the BTUs per cubic foot of product as gasoline.

Impco is very good. I am in Australia and dont know anything about your local market but I have a very good conversion by a manufacturer by the name of Prins. The really good thing about this conversion is the gas injectors they use are made by Keihin, who have been making fuel delivery systems for decades. Very good gear IMHO.

One thing about propane conversions (here in Oz we use what is called Liquid Petroleum Gas, LPG, which is a mixture of propane and butane) is that they come in at least three different styles.

1) The first and oldest is known over here as a "ring mixer" It is where a tubular ring with lots of holes on the inside arc is placed in the intake ducting and low pressure gas is introduced to the engine at a rate that is determined usually by the amount of vacuum that is present in the intake manifold (therefore indicating throttle position) This conversion is usually the cheapest to install but is definitely the least efficient. With the ring mixer LPG cars over here you can expect to lose up to 20% power and up to a third of your mileage compared to petrol (your regular gasoline) That said though, over here LPG is only one third the price of petrol so the cents/mile ratio is still a big winner. If your car has a carburettor this is your best choice for price and simplicity of installation

2) The second is VSI (vapour sequential injection) It works best on cars that have sequential fuel injection as the LPG computer that comes with the conversion uses information from the cars petrol computer to deliver very precise amounts of low pressure LPG via dedicated injectors and rubber tubing directly into the intake manifold as near as possible to the intake valves. My VSI system gives me no disernable drop in power and the decrease in fuel economy is no greater than 10-15% which is to be expected given that LPG has less heat than petrol for equal amounts compared. However, again, given that LPG is around 60 cents/litre in my home town at the moment and petrol is around $1.50 it is the hands down winner and the only reason I can still enjoy a V8. These systems can be adapted to carburetted cars but it is quite technical and consequently expensive.

3) The third system is only new in Australia and is known as "Liquid Injection". Similar to VSI it is injected directly to the intake manifold but unlike either of the other systems it is delivered at the same pressure as it is in the tank. There is no convertor that drops it to a lower pressure before intrducing it to the motor. Also, similar to a petrol system, there is a fuel pump in the tank that sends the LPG around a fuel rail cycling it back to the tank in a loop under full tank pressure. This system is said to deliver more power and ecomomy than petrol.

And thats a basic rundown on Propane/LPG systems.

Cheers

Hi Crane;

The second is VSI (vapour sequential injection) It works best on cars that have sequential fuel injection as the LPG computer that comes with the conversion uses information from the cars petrol computer to deliver very precise amounts of low pressure LPG via dedicated injectors . . .

Does this mean that the complete petrol fuel system is left in place, and can you switch between one and the other?

thanks for your input!

peter

Does this mean that the complete petrol fuel system is left in place, and can you switch between one and the other?

Yes phindrup. The entire petrol system is intact and switching between the two is seamless, even at high rpm. When the motor is started cold the engine runs on petrol for 100 seconds or until the coolant reaches 36 degrees Celcius (whichever happens first. In colder regions I imagine that that timing could be made longer) The LPG is then distributed sequentially to the cylinders by eight Keihin orange dot gas injectors via short rubber tubes and "nipples" that are screwed into the intake manifold as close to the petrol injectors as possible. Even when running on LPG the petrol fuel pump is running petrol through the rail to keep the fuel systen cool.

It's a great system that has increased the efficiency of the LPG motor in this country a great deal and, as mentioned above, its the only way I can enjoy a V8 in a place where a US gallon of fuel is around $5.50.

Thanks Crane, appreciated.

If you're in the US, see an article in Consumer's Report, Sept or Oct 2008. They give a brief overview of Natural Gas Fueling of Autos. Propane or LPG is liquified natural gas. In the article, they recommend researching where you will fill the tank, because there are not many outlets in the U.S. California has some, and Honda sells a Civic that runs on Nat Gas.

IF, and that's a big IF, you have a home fueling system, you can fuel your vehicle for about $1.00 a gallon. However, the IF is that the fueling system costs thousands of dollars.

Good Luck

Be Careful

Cannot say for other states, but here in Florida if you do a Propane conversion and do not PRE-PAY the Federal, State and Local taxes then its a FREE Go-To-Jail card for you with some heavy fines and probable jail time.

In Florida you are buying as window decal from the state. Florida DOR will estimate the potential miles you drive, compute the taxes and you pay up front before using any product.

Next year they read your mileage compute any adjustment and you pay in advance for the miles you may be driving.

If you are caught using any 'Home Brew' Bio-Diesel you will invoke the IRS that will presume you have been using the fuel product for THREE to SEVEN years and driving 30,000 miles per year regardless of what you might say. Compute 30,000 miles times $0.244 for the Federal, $0.156 for the State, $0.134 for the Florida Local Tax then multiply times the number of years from three to seven.

For three years: $ 48,060

For seven yesrs: $ 112,140.00

Then penalties and interest on top of this.

All it takes is one ill minded or pissed off neighbor to make a call to the IRS.

...If you are caught using any 'Home Brew' Bio-Diesel you will invoke the IRS that will presume you have been using the fuel product for THREE to SEVEN years and driving 30,000 miles per year regardless of what you might say. Compute 30,000 miles times $0.244 for the Federal, $0.156 for the State, $0.134 for the Florida Local Tax...

Wow! Quick question: Is that really 24.4c Fed, 15.6c State and 13.4c Local per MILE!?! Or per gallon based on average mileage of whatever vehicle you get busted home brewing in? If its per mile then.... gulp

Over here in Australia, there are cases of people making bio diesel from waste animal/vegetable fat/oil from delicatessens, fish and chip shops etc. They are being harrased to a certain extent by the authorites but as long as they are paying the 38c/litre federal tax they are so far avoiding any real problem. I'm sure it will (sooner than later) come to some kind of confrontation though as these clever people are making a fine product for their personal use for as little as 60c/litre (including tax) Fossil fuel diesel in Oz can be as high as AU$2.10/litre (US$6.30 US gallon!! at todays US$0.81 per AU$1) and averages around $1.70/litre.

The moral of this story... pay your taxes or make your own in fuel in extreme secret! Lol

"...Propane or LPG is liquified natural gas..."

Thats intersting. My understanding is that propane and butane (the ingrediants of LPG over here are byproducts of petroleum production as opposed to liquified natural gas LNG that is drawn straight from the ground. We have buses and trucks using LNG in this country but it has so far proven economically prohibitive to use in domestic small vehicles due to the enormous pressures that it must be subjected to to keep it liquified and the amount that must be used due to its lower heat value (much lower than even LPG) Anyone else got a view on this point?

Cheers

"...Propane or LPG is liquified natural gas..."

Thats intersting. My understanding is that propane and butane (the ingrediants of LPG over here are byproducts of petroleum production as opposed to liquified natural gas LNG that is drawn straight from the ground. We have buses and trucks using LNG in this country but it has so far proven economically prohibitive to use in domestic small vehicles due to the enormous pressures that it must be subjected to to keep it liquified and the amount that must be used due to its lower heat value (much lower than even LPG) Anyone else got a view on this point?

Cheers

LPG is NOT liquified natural gas, they are 2 seperate commodities with wildly different properties and set up.

LPG as another poster said is normally propane, C3H6, boiling point -40 and will have a pressure of 208 psi at 100 degrees F. Sometimes they mix butane in it in very hot climates. This will lower the pressure at 100 F down to 160 psia, so when it gets 125 F, the pressure on the tank remains under 200 psia.

LNG is liquified natural gas. The pressure on an LNG tank is typically less than 75 psig, and it is shipped at 10 psig. Inorder to keep the pressure down, the temperature is about -250F. The content is that it must be 98% CH4 and less than 2% C2H6.

LNG is not used on consummer vehicles but it is being used on comeercial vehicles in high pollution areas, like the Port of LA. It is somestimes use in diesel engines as a way to decrease fuel costs.

CNG is compressed natural gas, this is what consumers use. CNG can be anywhere from 88% to 98% CH4. the C2H6 is from 6% to 0%. The remainder is CO2 and N2. The natural gas in compressed to 300o psi. We use a term called gallons of gassole equivalent GGE. At you home, you are paying about $18/MMBTU for the gas. 8 gallons of gasoline is 1 MMBTU. So, gasoline is abut $3.5 per gallon BEFORE TAXES so thats $28/MMBTU. Your cost to fill up at home with CNG is $2.00 per GGE. Some states may waive their taxes and Utah is giving users a temporary rebate.

As stated also, the compressor is expensive and it takes 4 hour to fill a car up. Then after the car is full, you can only go 80 to 250 miles on a tank.

Don't know where US folks are getting their pricing information. Propane substituted for gasoline in road vehicles is taxed like gasoline. Failure to pay that tax is a felony.

And propane IS NOT lower in cost per mile unless one can buy more than 500 gallons at a time. If you are a farm/industrial user with than much consumption per month, the wholesaler will usually rent/lease/ or provide for free the storage tank for the propane.

In some areas of the U.S., there may be a local pricing advantage, but not most.

I grew up on a farm, and we eventually switched most everything to Propane (HD-5 grade with 98 min RON) because it is difficult to steal. It also burns much cleaner and oil changes can be much less frequent. Tractor engines running propane would last 10,000 hours or more before overhaul when 3000 hours on diesel was a lot.

US emission auto emissions regulations are complicated and modifying the fuel system may not be allowed.

McDuck : It's very easy to locate suppliers of conversion technology within the

continental U.S. - A propane conversion is about a $300.00 modification.It entails

a pressure tank , certified gas fittings to replace your carb/fuel injector , and often

the addition of stainless steel exhaust and intake valves - propane engines have a heat problem because they lack the liquid fuel's ability to cool engine components

when vaporizing the fuel.Because of propane's ability to leak into the atmoshere and

create explosive mixtures of fuel/air - all pressure gas fittings have to comply with

Federal standards.Try 'Globalspec.com' and ask for Industrial Propane conversions.