Elgas LPG Gas Blog

LPG Conversion - LPG Cars - LPG Gas Conversion - LPG Conversion Cost - The Myths

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

There are a number of 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 car and LPG gas conversion facts with you so you can make your own evaluation.

LPG Cars - LPG Gas Conversion - 7 Common LPG Conversion Misconceptions:

1. LPG gas conversion MPG average mileage cost (LPG mileage) no longer saves you money - FALSE

2. LPG car conversion causes a loss of performance - FALSE

3. LPG gas conversion voids your LPG car warranty - FALSE

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

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

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

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

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

LPG Gas Conversion and Other LPG Cars Conversions

LPG Conversion - LPG Car ConversionLPG car conversion and other LPG gas conversions 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 engine.

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

Dual fuel LPG cars and 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 engine is essentially a gasoline engine.

LPG Conversion - LPG vs Petrol Car - Convert Vehicle to Propane

LPG Conversion - LPG Car Conversion

LPG conversion is when a petrol (gasoline) powered vehicle is converted to run on auto LPG (convert vehicle to propane) to reduce LPG 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 conversion 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 engine, is converted to improve LPG mileage fuel costs and reduce emissions running on LPG vs petrol cars. Auto LPG 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 gas conversion fuel intake manifold system must be modified to allow for the delivery of an auto LPG (Autogas) – air mixture to the combustion chambers.

LPG Conversion Kit for LPG Cars - LPG Gas Conversion - LPG Conversion Kit Installation

Some LPG conversion kits for LPG cars can be purchased online. Other LPG conversion kits can only be purchased for cars on an LPG kit installation basis. LPG conversion kit installation must be done by licensed gas fitter at your local LPG coversion shops.

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

Four Types of LPG Gas Conversion Systems

The four types of LPG gas conversion systems incude:

1. Converter-and-mixer systems

2. Vapour phase injection (VPI)

3. Liquid phase injection (LPI)

4. Liquid phase direct injection (LPDI)

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

Best LPG Conversion System

The best LPG conversion system is arguably the liquid phase direct injection (LPDI) system. LPDI systems are the latest generation in LPG gas conversion technology.

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

LPG Cars vs Petrol Cars

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

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

• LPG cars have lower LPG mileagerunning costs vs petrol cars.

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

LPG conversion may actually prolong LPG cars engine life.

• Auto LPG (Autogas) LPG 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 gas 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.  However, the cost is typically recovered quickly through the realised LPG conversion MPG 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 mileage result is that you still save about 40% on your LPG mileage costs with an LPG gas conversion.

This LPG mileage savings will more than cover the cost of the LPG conversion, if you are a driver that racks up a high kilometre count.

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 conversion, LPG cars, LPG fuel consumption, LPG gas conversion MPG, LPG conversion cost and auto LPG.


How Much Does LPG Conversion Cost-Price - How Much to Convert Car to LPG

How much does LPG conversion (convert vehicle to propane) cost depends on the model and engine. How much to convert a car to LPG or the LPG conversion price-cost also varies based on the type of LPG engine conversion system selected. An LPG car conversion price can range from around $2,500 to over $4,000 for LPDI models.

Converter-and-mixer systems have the least expensive LPG conversion cost whilst Liquid Phase Direct Injection (LPDI) are the most costly.

LPG Cars Still Save You Money - LPG Average Mileage - LPG Conversion MPG

LPG average mileage cost, or LPG conversion MPG still saves you money. Auto LPG (Autogas) consumption - LPG mileage - for LPG cars is greater than petrol but it is more than offset by a much lower LPG cars fuel price. 

The reason for the difference in 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 mileage. 

This equates to only about a 14% difference.

Some people make wild claims regarding the comparative LPG milage (LPG conversion MPG) of LPG cars versus petrol powered cars. 

The only way to compare LPG 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 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.  

Selecting the Ford Falcon Petrol vs Ford Falcon LPG, we can compare auto LPG mileage data for identical vehicles. 

This auto 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 mileage) for the LPG cars. 

So, petrol consumption is only about 20% less in comparison to the LPG mileage.

LPG Conversion MPG or KM/L LPG versus Petrol Consumption

LPG Average Mileage - LPG Conversion MPG or KM/L

LPG Average Mileage - LPG Conversion MPGLPG average mileage (LPG mileage), LPG conversion MPG (Miles Per Gallon) or KM/L 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 LPG MPG 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 average mileage cost favourable.

LPG Conversion Cost: How Much to Convert Car to LPG

LPG conversion costLPG conversion cost can range from around $2,500 to over $4,000 for LPDI models.

LPG conversion cost (convert vehicle to propane) is dependent upon which type of equipment you choose, with older Converter-and-mixer systems being the least expensive.

Is LPG Conversion Worth It

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

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

No Loss of Performance with LPG Conversion

When considering LPG cars vs petrol performance, many years ago the loss of performance, compared to petrol, had some basis in fact. Now, LPG cars 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 LPG (propane), as compared with petrol (gasoline) performance.

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

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

LPG Car Conversion Does Not Void Your Warranty

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

LPG conversion may actually prolong engine life.

LPG conversion systems are so reliable that more than 1 million LPG cars 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 gas conversion systems come with full factory warranties. 

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

LPG Cars are Just as Safe as Petrol

LPG cars are safeLPG cars and trucks have been used safely in Australia for decades. Australian LPG 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 safety of LPG cars 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 LPG Autogas Tank in the Boot of LPG Cars

Toroidal LPG tank in spar tyre well.The new toroidal 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 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 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 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.