Towing on Gas

Quite often you get a pleasant surprize John0.
However the sucess of gas depends a lot on the quality of the installer and subsequent tuning.

Gas has less energy than petrol and so you have to burn more - around 20-30% more and it delivers less maximum power however the way it burns generally contributes to more torque and this is good for towing.

Gas is not the econonic winner that it used to be any more unfortunately, now that its cost is up.

If I was having Gas installed I would be going with Injected Gas rather than the older style mixer system. It costs around $5k but you will save that money over a few years. From what I understand you will not have the problem with losing power like the mixer style. I have the. Older style mixer on my 4.2 Patrol and at the current price of LPG there is no saving at all.

Are you talking about a petrol conversion or diesel/gas assisted conversion?

G'day Johno
Purely the fact you said converted to Gas and not assisted by gas indicates a petrol vehicle.

All petrol vehicles run on gas, They don't run on petrol as such, and carbies or fuel injection is designed to evaporate the petrol and turn it into a gas in the air charge in the cylinder so it can be readily burnt. LPG is delivered as a gas into the cylinder and doesn't cool the incoming charge air as much as the refrigerant effect of evaporating the petrol spray does. LPG as a gas does have different burn characteristics but properly tuned, both ignition and mixture, should see a gas vehicle outperform a petrol.

In correct mixtures will cause backfires through leanness but that is eliminated with modern injected gas systems.
It will use more litres/hundred though and the running cost difference although cheaper than petrol isn't as great as it used to be

Your cooling system will have to be in top shape as the gas may cause the engine to run hotter. Ensure every part of the cooling system is functioning correctly.

G'day johno59
We have run our GU Nissan Patrol on gas for the last 4 years. Our fuel price has averaged $0.96 a ltr.
When approaching a steep hill (towing our 26' Windsor) I generally switch over to petrol as I will need the extra low down power that petrol gives.
But with LPG in country areas being up to twice as much as they pay in Sydney or Melbourne I may not convert my next vehicle to gas.
I agree with the comment that the tuneing of the engine is vital.
Hope that helps
Stay well and stay safe
PeterM (Qld)

johno, I have run vehicles on gas for the last 30 years and have not looked back. I have been lucky enough to have the right systems installed, and no problems at all, while people around me say otherwise. Our last vehicle was a 100 series v8 Landcruiser.(the best vehicle and nicest vehicle I have ever owned and driven) On a recent trip we were towing our caravan into strong headwinds both ways.The LPG prices in the country are excessive and I don't know how this can be legal. The prices in proportion from city to country do not compare with both petrol and deisel. I have now just changed my vehicle to a turbo deisel Prado. I have always done big mileages in all my vehicles and up till now had a very good run with gas. The Landcruiser was gas injected and there was absolutely no difference in power from petrol or gas. The economy vaied only a little.

I hope this helps.

Laurie.

Having had several LPG powered vehicles over many years and towing a 2 tonne nam with it I can say that, providing the tune is set for gas, there is no difference towing with gas or petrol other than the savings on gas. These savings are diminishing as time goes on and as the price of LPG climbs.

I would convert my 100 series V8 to gas but the savings may not cover the cost of conversion for many many years to come so I am staying with petrol. Then there is the siting of tanks, relocation of the spare wheel etc. All this comes into the equation for consideration.

I was a great advocate of gas up till a couple of years ago but the price and availability away from the major centres is eating away any gains more lately.

If I bought a vehicle already converted it would be a different matter but the cost of conversion to an injected system makes it unviable to convert I believe, for me at least.

Cheers, Bruce.

I bought a Rodeo 3.2 litre with a factory fitted Impco gas system a few years ago and used it to tow a 16' Coromal. Plenty of torque and good on the hip pocket at the time. The only problem was the Impco system was substandard when compared to others. When I got the vehicle serviced I also had to have to get the gas system serviced, I never found a service centre that serviced both systems. Fuel availability in WA at the time was abysmal in country areas and the price simply went through the roof. Also had problems refueling - it always overfilled, worrying to say the least. The Impco system in the Rodeo was recommended for starting on gas, but if your foot touched the accelerator before starting the resulting explosion in the gas system destroyed the diaphragm. The Rodeo was an excellent tow vehicle and cheap to run, even on petrol, but very dear for for services: shim buckets, special plugs, etc.

Hi
I have had a gas mazda bravo and pajero and used both for towing campers and a van. As stated gas will use about 20% more litres than petrol. Because the price of gas has risen substantially and will continue to rise due to increased govt tax, gas is no longer the bargain fuel it used to be. Gas systems need to be set up right and have excellent ignition and cooling system or you will experience problems, ie backfires which can blow up air filter boxes, seals drying and leaking oil. Gas is dearer in remote areas and can be a problem to find in some locations. Because more gas is used in comparison to petrol, a further problem is range. If a tow vehicle typically uses 16L/100km on petrol towing, it can be expected to use 20L/100k on gas. Taking into account that most gas tanks are around 70 litres, range is limited to 350km. Gas is not like petrol or diesel, where a few jerry cans of extra fuel can be carried. My advice to anyone contemplating gas is to go diesel instead. I am achieving 11 - 12 litres per 100km towing a 14 ft van at speed limits on diesel. This is cost wise the equivalant to towing on gas 4 years ago when gas was much cheaper. I also dont have the problem of fuel availability. Its a sad fact that the govt has seen fit to increase tax on gas. It is clean, has negligible power difference to petrol, and doesn't dirty oil like petrol and diesel. If gas were still half the price of petrol, I would consider it. But at 1.10 compared to 1.50 for petrol locally it is not worth the hassles involved.

regards