Autogas for Australia

LPG Gas Conversion Facts

LPG gas conversion can be done with almost all vehicles fuelled by petrol. They can be converted to LPG operation at a reasonable cost.

Dual-fuel LPG systems allow a vehicle to operate on either LPG or unleaded petrol and can almost double a vehicle’s range.

The petrol tank still remains in the car and the driver can switch from gas to petrol or vice-versa.

LPG Conversion

In simple terms, 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.

LPG Gas Conversion

LPG gas conversion is when a petrol (gasoline) powered car, with an internal combustion engine, is converted to run on LPG in order to save money on fuel. LPG gas conversion is frequently dual fuel, running on either LPG or petrol (gasoline) after it’s converted.

Converting an engine to LPG is actually beneficial for your car.

LPG is a cleaner burning fuel than petrol, so engine life is actually extended with conversion.

Engine oil and spark plugs need changing less often when you convert to LPG, so service intervals can be increased.

LPG conversion may prolong engine life.

The time required to convert to an LPG system varies.

A typical family sedan LPG conversion, with a single boot-mounted tank, should take only one to two days.

A large four-wheel drive LPG gas conversion, with multiple tanks, might take two to three days.

You should tell your insurance company when you convert your vehicle LPG.

They should revise the coverage to reflect the value of the system.

Note that any vehicle with a compliance plate dated after December 2003 that is converted to run on LPG must be fitted with a system that has passed current emissions test standards.

Find Qualified LPG Installers & Service

Types of LPG Gas Conversion Systems

• Converter-and-mixer LPG gas conversion systems are the oldest style, dating back decades and still widely used.

The liquid fuel is converted into vapour and then mixed with air before going into the intake manifold.

• Vapour phase injection (VPI) systems use a converter-and-mixer system, but the gas exits the converter under pressure and is injected into the intake manifold.

Electrically controlled injectors improve the metering of fuel to the engine, fuel economy and power, as well as reducing emissions.

This has been the most popular type LPG gas conversion system in recent years.

• Liquid phase injection (LPI) systems inject liquid directly into the intake manifold, where it vaporises, not using a converter.

The fuel vaporising in the intake manifold cools and increases the density of the intake air, substantially increases power output, improves fuel economy and has lower emission, when compared to VPI systems.

• Liquid phase direct injection (LPDI) are the most advanced LPG gas conversion systems, injecting liquid LPG directly into the combustion chamber.

The LPG instantly vaporises, cooling the combustion chamber fuel-air mixture during the compression stroke, with further performance and emission improvements.

Vapour vs Liquid Injection

There are two types of LPG gas conversions, vapour and liquid injection.

The difference is in how the LPG is delivered to the engine cylinder combustion chamber.

Liquid LPG systems are the latest generation in automotive LPG fuel system technology.

You get a substantial fuel savings with LPG Autogas, combined with equal engine performance, impeccable drive-ability and lower tailpipe emissions.

Learn more about Liquid Injection LPG vs Vapour Injection Conversions

No Loss of Performance

Many years ago, when LPG gas conversions were in their infancy, the loss of performance issue had some basis in fact. However, it is no longer true.

A vehicle with a state-of-the-art liquid LPG system produces at least the same amount of power when running on LPG, as compared with running on petrol.

No Big Tank in the Boot

The days of the LPG tank taking over your boot are gone.

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

The new toroidal LPG tanks are doughnut shaped and typically are fitted within the spare wheel well.

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

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


LPG systems fitted by an installer to a new vehicle after purchase will generally be warranted by the installer and the equipment supplier.

The terms and conditions of the warranty vary so you should check before converting.

Extended warranty period options are available through some installers.

Your new car warranty remains intact unless the LPG conversion directly causes the problem.

Given the long track record of LPG conversions and ever improving technology, it would be rare that the conversion would ever cause a problem that would affect your warranty.


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You may also wish to see these informative blogs:

Are LPG Cars Safer than Petrol?

7 LPG Conversion Myths

The Forgotten Fuel: Autogas & LPG Conversions

How to Beat the Petrol Price Cycle

Liquid Injection LPG vs Vapour Injection Conversions

Diesel Exhaust Causes Cancer | Alternatives

Australia Needs a Good 4-Cylinder LPG Powered Car


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