Elgas LPG Gas Blog

LPG Conversion - LPG Conversion Price - LPG vs Petrol (gas or gasoline) Conversion Myths

What will it cost me for an LPG conversion? Depending on which type of system is installed, LPG conversion price average around $2,500 for a basic converter-and-mixer to over $4,000 for a liquid phase direct injection. LPG on average is about 50% of the petrol price but you typically use about 20% more LPG. So, you still save about 40% on fuel.

LPG conversion (autogas conversion) is when a petrol (gasoline) powered vehicle, with an internal combustion engine, is converted to an LPG car or LPG vehicle in order to save money on petrol vs LPG gas car mileage (LPG average mileage) cost. A new engine fuel intake system, LPG tank and filler connection are added as part of the LPG conversion (LPG engine conversion).

There are a number of petrol vs LPG conversion fallacies that persist for LPG vehicles because of a lack of information. To help clear the air, I’d like to share some LPG cars and LPG conversion facts with you so you can make your own evaluation.

LPG Car Conversion - LP Gas Conversion - LPG Gas Conversion

An LPG car conversion includes installing an LPG tank to your vehicle (in addition to the petrol tank), added piping, components, and a new intake manifold system. Your car will then run on both fuels.

LPG gas conversion (liquified petroleum gas) can be done with virtually any petrol (gasoline) powered cars, making them dual fuel cars. The advantage is that LPG fuel price is about 50% less than petrol. You also gas a cruising range of about double the distance, with two fuel tanks.

LPG Conversion - LPG Car Conversion

LPG conversion is the addition of a second fuel system including an LPG tank, intake manifold modifications, a new ECU and various fittings. These additions enable the LPG conversion to run on both fuels. Here is a summary of an LPG conversion:

  • LPG conversion starts with a petrol powered vehicle, powered by an internal combustion engine

  • An LPG fuel tank is added, fitting in the spare tyre well, as an LPG cylinder in the boot or under the vehicle

  • A vaporiser is added to convert the liquid LPG into vapour, unless the LPG conversion is direct injection

  • The LPG conversion fuel intake manifold or injectors is added for the delivery of LPG to the combustion chambers

This is just a condensed LPG conversion summary. More conversion details are provided below.

LPG Cars & LPG Vehicles - LPG Powered Cars

Autogas is the name used for LPG – liquefied petroleum gas – when it is used in LPG vehicles with internal combustion engines, as well as in fixed uses such as generators. It is a mixture of propane and butane.

Liquefied petroleum gas (LPG) is commonly called autogas when it is used as a fuel in LPG powered cars with internal combustion engines. Most LPG gas cars undergo an LPG conversion process to be driven by LPG autogas. Autogas can be pure propane or a mixture of propane and butane.

There are four different types of LPG conversions: converter-and-mixer, vapour phase injection (VPI), liquid phase injection (LPI) and liquid phase direct injection (LPDI).

LPG Conversion Price - LPG Conversion Cost

LPG conversion cost

LPG conversion price (LPG conversion cost) depends on the model and LPG engine conversion. LPG conversion price also varies based on the type of LPG conversion system selected. An LPG  conversion price can range from around $2,500 for Vapour phase injection (VPI) to over $4,000 for LPDI models.

LPG conversion price (LPG conversion cost) is dependent upon which type of equipment you choose, with older Converter-and-mixer systems being the least expensive LPG conversion price whilst Liquid Phase Direct Injection (LPDI) are the most expensive LPG conversion price.

Is LPG Conversion Worth It

In answer to the question "Is LPG conversion (autogas conversion) worth it?" the response would be "YES". LPG conversion price is worth it because you still save about 40% on your LPG conversion MPG with your LPG conversion cost.

LPG Fuel Consumption

LPG fuel consumption costs shows that LPG fuel economy was 12.3L/100km LPG mileage vs petrol mileage of 9.9L/100km. However, the LPG fuel consumption puzzle is solved by the fact that LPG is approximately 50% less expensive, more than offsetting the mileage.

LPG Cars - LPG Vehicles - LPG Conversion MPG

Autogas is another name for LPG - liquefied petroleum gas – when used as fuel in LPG vehicles with internal combustion engines. It is typically a mixture of propane and/or butane, which can also be sued for fixed applications, like generators.

7 Petrol vs LPG gas car mileage Myths:

1. Petrol vs LPG gas car mileage (LPG mileage): LPG conversion MPG or LPG average mileage (LPG mileage) no longer saves you money - FALSE

2. LPG conversion (autogas conversion) causes a loss of performance - FALSE

3. LPG conversion (autogas conversion) voids LPG cars warranties - FALSE

4. LPG cars are less safe than petrol cars - FALSE

5. There is a loss of boot space with LPG vs petrol cars - FALSE

6. Auto LPG (Autogas) is hard to find - FALSE

7. LPG vs petrol cars are hard to fill  (See Video) - FALSE

So, in considering LPG cars, LPG vehicles and LPG conversion MPG, here are some of the things to consider...

LPG Car Conversion - LPG Vehicle Conversion

Here is a summary of an LPG car conversion (LPG vehicle conversion):

  • LPG car conversion (LPG vehicle conversion) starts with a petrol powered car, powered by an internal combustion engine

  • An LPG fuel tank is added, fitting in the spare tyre well, as an LPG cylinder in the car boot or under the vehicle

  • A vaporiser is added to convert the liquid LPG into vapour, unless the LPG car conversion is direct injection

  • The LPG car conversion fuel intake manifold or injectors is added for the delivery of LPG to the combustion chambers

Auto LPG Conversion

Auto LPG conversion is an option for virtually any petrol powered auto or other vehicle. They become dual fuel cars after auto LPG conversion, running on either LPG or petrol. The biggest advantage of LPG conversion is that LPG is about half the cost of petrol. The savings is even greater with 100+ octane LPG compared to 98 octane petrol.

LPG Conversion - Autogas Conversion

LPG Conversion - LPG Car ConversionLPG conversion (autogas conversion) are fueled by auto LPG (Autogas), which is propane, butane or a mixture of the two. LPG cars are powered by an LPG fueled internal combustion LPG engine conversion.

An LPG tank and filler connection is added to the LPG cars or LPG conversion as part of the LPG conversion (convert vehicle to propane).

Dual fuel LPG cars and LPG vehicles have two fuel tanks after the LPG conversion (LP gas conversion), with one for auto LPG (Autogas) and one for petrol, selectable by the LPG car driver.

Some LPG cars are auto LPG (Autogas) only but the LPG engine conversion is essentially a gasoline engine.

LPG Conversion - LPG vs Petrol (gas or gasoline) Car Mileage - Convert LPG Vehicle to Propane

LPG Conversion - LPG Car Conversion

LPG conversion (autogas conversion) is when a petrol (gasoline) powered vehicle is converted to run on auto LPG (convert vehicle to propane) to reduce LPG vs petrol (gas or gasoline) mileage fuel costs, maintenance costs and emissions. LPG conversion vehicles include LPG – Liquefied Petroleum Gas – LPG cars, SUVs, light commercial trucks, utes (pick-up trucks) and tradesperson vans.

LPG cars and other LPG vehicles (convert vehicle to propane) are powered by auto LPG (Autogas), which is typically a fuel blend of propane and butane.

Auto LPG conversion (LP gas conversion) is when a car powered by a petrol internal combustion LPG engine conversion, is converted to improve LPG average mileage fuel costs and reduce emissions running on petrol vs LPG gas car mileage (LPG mileage). Auto LPG conversion (autogas conversion) are frequently dual fuel, running on either auto LPG (Autogas) or petrol (gasoline) after the LPG conversion.

You start with a petrol powered car, or other vehicle, powered by an internal combustion engine.

An LPG fuel tank and filler connection must be added, along with the existing petrol tank, as part of the LPG car or LPG gas conversion (convert vehicle to propane).

The tank in an LPG conversion can be a round toroidal tank that fits in the spare tyre well or a cylinder that goes in either the boot (trunk) or under the LPG vehicle, if there is sufficient room and clearance.

The LPG conversion fuel intake manifold system must be modified for the LPG engine conversion to allow for the delivery of an auto LPG (Autogas) – air mixture to the combustion chambers.

LPG Conversion Kit for Cars - LPG Conversion Kit Price - LPG Conversion - LPG Kit Installation

Some LPG conversion kits for cars can be purchased online with an attractive LPG conversion kits for cars price. Other LPG conversion kits for cars can only be purchased for LPG cars on an LPG kit installation basis. LPG kit installation must be done by licensed gas fitter at your local LPG coversion (autogas conversion) shops. In this case, the LPG conversion kits for cars price typically includes the cost of installation.

The LPG conversion kits are for LPG kit installation on specific car models, including LPG conversion kit type and year of manufacture.

Four Types of LPG Conversion Systems

The four types of LPG conversion systems incude:

1. Converter-and-mixer LPG conversion (autogas conversion) systems

2. Vapour phase injection (VPI) LPG conversion

3. Liquid phase injection (LPI) LPG conversion

4. Liquid phase direct injection (LPDI) LPG conversion (autogas conversion)

A manual fuel selector switch and gauge is added inside the car.

Best LPG Conversion System - Best LPG System

The best LPG conversion system (best LPG system) is arguably the liquid phase direct injection (LPDI) system. Depending on which type of system is installed, LPG conversion price average around $2,500 for a basic converter-and-mixer to over $4,000 for a liquid phase direct injection.

LPDI systems are the latest generation in LPG conversion technology. The LPG conversion price for an LPDI LPG conversion would be at a premium, compared to other systems.

You get a substantial LPG fuel consumption savings (LPG average mileage) with an LPDI LPG conversion, combined with equal or better LPG engine conversion performance, LPG conversion MPG, great drive-ability and lower tailpipe emissions. It truly is the best LPG conversion system (best LPG system).

LPG Cars vs Petrol Cars Mileage - LPG Conversion Price

LPG vs Petrol CarsComparing auto LPG cars vs petrol cars and petrol (gas or gasoline) vs LPG conversion MPG, the most important difference is that LPG cars and LPG vehicles save you about 40% on LPG average mileage (LPG mileage) costs.  LPG cars have lower emissions, lower service costs and prolonged engine life in an LPG conversion MPG and petrol vs LPG gas car mileage comparison. 

With over 100 octane, auto LPG (Autogas) can also be used in place of even premium grade petrol.

• LPG cars have lower LPG average mileage (LPG mileage) running costs vs petrol cars.

When comparing the cost of fuel for LPG cars vs petrol cars and petrol (gas or gasoline) vs LPG gas car mileage, auto LPG (Autogas) is about half the price of petrol but your LPG conversion will use about 20% more LPG average mileage (LPG mileage) than petrol.

LPG conversion (autogas conversion) may actually prolong LPG vs petrol (gas or gasoline) engine life.

• Auto LPG (Autogas) LPG average mileage is less expensive than petrol or diesel.

Engine oil and spark plugs need changing less often with an LPG conversion, so service costs are reduced.

Environmental benefits of an LPG conversion (autogas conversion) include reduced particulate, CO2 and NOx emissions,

• Auto LPG (Autogas) has octane ratings over 100 allows for higher compression ratios, which can increase power output of LPG cars.

• The biggest negative is the extra cost involved in LPG conversion price.  However, the LPG conversion price is typically recovered quickly through the realised LPG conversion MPG or petrol vs LPG gas car mileage savings.

• In some countries it may be a bit more difficult to find service stations for LPG cars but, in most countries, they are becoming more numerous every year.

The LPG average mileage (LPG mileage) result is that you still save about 40% on your petrol vs LPG gas car mileage costs with an LPG conversion.

This LPG average mileage (LPG mileage) savings will more than cover the LPG conversion price, if you are a driver that racks up a high kilometre count.

LPG Conversion MPG - LPG Fuel Economy

As anticipated, the LPG car MPG was less than the petrol car at 12.3L/100km LPG mileage vs petrol mileage of 9.9L/100km. However, the cost of LPG is about 50% less than petrol, providing a net savings of around 40% for LPG. If you are substituting 100+ octane LPG for 98 octane premium petrol, the LPG savings are even more substantial.

So, it's not so much about miles per gallon (MPG) - kilometers per litre - as it is about miles-km per dollar of fuel cost.

Where Do the LPG Conversion Myths Come From?

Sometimes tall tales get told so many times that people start accepting them as facts. 

The problem can also come from very out-of-date information that may have, at one time, been factual but is no longer true. 

This is the case with the myths surrounding LPG vs petrol cars, LPG conversion (autogas conversion), LPG cars, LPG vehicles, LPG conversion price, LPG mileage, LPG gas conversion MPG and auto LPG.

 

LPG Cars Still Save You Money - LPG Gas Car Mileage

One of the biggest advantages of LPG vs petrol cars and vehicles is LPG average mileage (LPG mileage) cost. 12.3L/100km LPG mileage vs petrol mileage of 9.9L/100km, in otherwise identical cars, but then the LPG cost about 50% less so you still save a substantial amount of money with LPG.

LPG conversion MPG still saves you money after LPG conversion price. Auto LPG (Autogas) consumption - LPG conversion MPG - for LPG cars is greater than petrol vs LPG gas car mileage but it is more than offset by a much lower LPG cars fuel price. 

The reason for the difference in LPG conversion MPG (LPG mileage) is the difference in energy content and the LPG conversion MPG cost. 

For example, unleaded E10 has 31.2Mj/L while auto LPG has 26.8Mj/L LPG average mileage (LPG mileage). 

This equates to only about a 14% difference.

Some people make wild claims regarding the comparative LPG average mileage (LPG conversion MPG) of petrol vs LPG gas car mileage (LPG mileage). 

The only way to compare LPG mileage vs petrol mileage accurately is using the identical make, model, year, engine and transmission, with the only difference being the fuel. 

This removes all of the other petrol vs LPG gas car mileage (LPG mileage) variables including the human factor, like a light or heavy foot.

We can do this using the info from the Green Vehicle Guide government website. 

Ford Falcon LPG Fuel Economy Consumption - LPG Mileage vs Petrol Mileage

Ford Falcon LPG fuel economy consumption was 12.3L/100km for the LPG Falcon XT LPG vs petrol mileage of 9.9L/100km for the petrol XT. This Falcon LPG mileage vs petrol mileage is based on a real world test of LPG fuel economy consumption. As expected, LPG gets less MPG but fuel economy must also consider the cost of the fuel. LPG costs about 50% less so you still save a substantial amount of money (about 40%) with LPG.

The numbers are from these otherwise duplicate Ford Falcon vehicles in the same make, model, engine and transmission, with the only difference being the LPG conversion.

If you are substituting 100+ octane LPG for 98 octane premium petrol, the savings are even more substantial, with similar L/km results as the real world test.

Ford Falcon LPG fuel economy consumption is documented, with Ford Falcon Petrol vs Ford Falcon LPG, we can compare LPG mileage vs petrol mileage data for identical vehicles.  The Ford Falcon LPG fuel economy consumption was 12.3L/100km for LPG conversion MPG.

Ford Territory LPG consumption would be similar to the 12.3L/100km.

This auto LPG average mileage (LPG mileage) data was available for all vehicles sold in Australia. 

The numbers in these otherwise duplicate vehicles are 9.9L/100km for Petrol cars and 12.3L/100km LPG conversion MPG (LPG average mileage) for the LPG cars. 

So, petrol consumption is only about 20% less in a petrol vs LPG gas car mileage comparison (LPG mileage).

LPG Conversion MPG or KM/L LPG versus Petrol Consumption

LPG Conversion MPG - LPG Gas Car Mileage - LPG Average Mileage - LPG Mileage

LPG Average Mileage - LPG Conversion MPGLPG currently costs about A$0.75 per litre whilst unleaded petrol costs around A$1.35. The difference is even more dramatic with premium petrol, as 98 octane petrol cost A$1.60 or more per litre whilst LPG, which is over 100 octane, is A$0.75 per litre.

Whilst petrol consumes about 20% less fuel per km or mile, the huge difference in pump price still provides huge savings for the LPG user.

LPG average mileage (LPG mileage), LPG conversion MPG and LPG gas car mileage are measures of fuel efficiency. The resulting LPG conversion MPG and LPG average mileage is breakeven when the price of LPG is 20% less than petrol. For example, if petrol is $1.50, breakeven for petrol vs LPG gas car mileage (LPG mileage) is $1.20. 

However, LPG pricing is much lower than that, currently at around $0.75 in Sydney, so about 50% less. This makes the LPG gas car mileage cost (LPG mileage) favourable.

LPG vs Petrol Performance - No Loss of Performance with LPG Conversion

No Loss of Performance with LPG Conversion

When considering LPG vs petrol (gas or gasoline) performance, many years ago the loss of performance, compared to petrol, had some basis in fact. Now, LPG vs petrol performance is equal to or better than that of petrol in many vehicles.

An LPG car with a state-of-the-art liquid LPG system produces at least the same amount of power when running on auto LPG (propane), as compared with petrol (gasoline) performance.

Liquid injection LPG conversion systems are the latest generation in automotive LPG conversion system technology

You get a substantial LPG average mileage savings with an LPDI LPG conversion, combined with equal engine performance, LPG conversion MPG, impeccable drive-ability and lower tailpipe emissions.

LPG Conversion Does Not Void Your Warranty - LPG vs Petrol Engine Life

Your new car warranty remains intact unless the LPG conversion (autogas conversion) directly causes the problem.  Given the long track record of LPG cars and LPG vehicles, LPG vs petrol engine life and ever improving technology, it would be rare that the LPG conversion would ever cause a problem that would affect your warranty.

Comparing LPG vs petrol engine life LPG conversion may actually prolong engine life.

LPG conversion systems are so reliable that more than 1 million LPG conversion systems have been factory fitted by automobile manufacturers around the world. 

Ford chose a Liquid Phase Injection LPG conversion system for their factory equipped LPG Falcon EcoLPi. 

Holden elected to go with a Sequential Vapour Gas Injection LPG conversion system for the LPG Ecoline Commodore. 

Both LPG conversion systems come with full factory warranties. 

The same liquid and vapour LPG conversion technologies are also available for aftermarket LPG conversions.

The manufacturers of LPG conversion systems (some call them kits) are so confident that they offer extended warranties on their LPG cars. 

For example, Sprint Gas offers a 3 years / 100,000km warranty on late model LPG conversion.

LPG Cars are Just as Safe as Petrol - LPG vs Petrol Safety

LPG cars are safeLPG cars and trucks have been used safely in Australia for decades. Australian LPG conversion (autogas conversion) systems must meet the strict requirements of the Australian Standard AS1425, which covers specifications, installation and maintenance.

LPG conversion systems are fitted with a myriad of safety devices and design considerations. 

Pressure relief valves, automatic shut-off systems, back check valves, and heavy gauge steel tanks are amongst the safety features employed.

The litmus test for the LPG vs petrol safety of LPG cars and LPG vehicles is the cost of insurance. 

It costs no more to insure LPG cars than petrol cars. 

If LPG cars were more dangerous, you can bet the insurance companies would be charging more to insure them.

No Big Auto LPG (Autogas) Tank in the Boot of LPG Cars

Toroidal LPG tank in spar tyre well.The new toroidal auto LPG (Autogas) tanks are doughnut shaped and typically are fitted within the spare wheel well of LPG cars. The days of the auto LPG (Autogas) tank taking over your boot are gone. 

There are new LPG tank innovations that preserve your boot space for important things, like golf clubs and luggage!

They come in various sizes to fit just about any LPG car, ute or SUV. 

They are also available in versions suitable for either liquid or vapour injection LPG conversion systems.   

Toroidal LPG tanks come in both interior and exterior mounted styles. 

The spare is typically replaced by a small emergency inflation kit.

Auto LPG (Autogas) is Easy to Find

Auto LPG being hard to find may be the biggest myth of all. There are over 3,000 auto LPG Autogas outlets in Australia.  In fact, we have one of the most extensive auto LPG distribution networks in the world.

LPG Cars Are Easy to Fill

While the auto LPG nozzle and procedure for filling LPG vs petrol cars is different, it is not difficult.  Virtually anyone can fill LPG cars. 

Here is a ‘how to’ video to show you how easy it is to fill up with auto LPG:

Video courtesy of CarAdvice

View more Autogas related blogs

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The information in this article is derived from various sources and is believed to be correct at the time of publication. However, the information may not be error free and may not be applicable in all circumstances.