Diesel/LPG

[Onethirty]

Looking for some advice on this; what sort of fuel usage improvement from running a diesel/lpg mix?

Thanks

[Nat130]

This is an interesting topic...

There is some info on this website (and probably many more), its about $4000 to get it installed.

http://www.webwombat.com.au/motoring/news_reports/4wd-diesel-lpg-conversion.htm

[97discotdi]

I have the dieselgas australia system on my 300tdi, it has a fairly basic computer that controls the amount of opening off a stepper motor that supplies lpg to the suction of the turbo. The programme can be adjusted through the rev range to vary the degree of openning at any given revs. Initially mine was set up to give about 30% lpg to diesel this gave a huge increase in power(could keep up with my mates 2005 3.2DID Pajero) however because the tank is only approx 20ltrs usable it required topping up every 500k's. Monday this week I had it toned down to decrease the gas usage, I haven't finished the first fuel test yet but I have done 550k's and the fuel gauge is showing between 3/4 and 1/2 a tank and the gas is showing approx 1/2 a tank. When I have filled them up I will let you know the consumption. Before it was detuned I was doing 900k's to 70litres diesel 30litres lpg. But as I said the power was right up there. Now the power is down to a bit better than standard but it depends on the fuel consumption. I am going to keep playing till I find the right compromise. Mark Collins at diesel gas australia has been great to deal with.

[Onethirty]

Hi 97discotdi

My interest lies in extracting the best possible range for this vehicle as we are setting it up for long-range touring. I am about to order a 70 litre auxiliary fuel tank which will give me 120+70+40(jerry cans) for a total capacity of 230 litres and a range in the region of 1800 klms, which covers almost everything that I will need to do.

The decision process now revolves around whether I can extract the same endurance by installing an LPG system to mix the fuels instead of the auxiliary tank. Working on 160 litres I need to improve fuel efficiency from 12.5klms per 100 to 8.7klms per 100 on average looking at it from a usage perspective only. Clearly there is power along with cost improvements that could sway the decision.

From an installation perspective; I get a rebate on the LPG that brings it back to an acceptable cost versus the auxiliary fuel tank after installation.

Looking at your numbers at present it looks like you were getting around 7.8/8.0 litres per 100. My understanding is the LPG should be around 25% of the diesel capacity....

Thanks gfor your thoughts and Id be keen to hear how the consumption goes.

[abaddonxi]

Have you seen this site?

http://www.dieselgas.com.au/economy.htm

Cheers
Simon

[97discotdi]

Thought I would go and fill up here is the numbers 575k's 48.5l diesel 9l lpg. Should be accurate I use the same bowsers each time

[mcrover]

8.43L/100km Diesel
1.22 L/100km LPG

Thats great, is that around town or trip?

[isuzurover]

I don't see why you can't turn down the fuelling on the pump (on a Bosch VE for example) and increase the LPG fuelling???

[Utemad]

I don't see why you can't turn down the fuelling on the pump (on a Bosch VE for example) and increase the LPG fuelling???

What would happen if you ran out of LPG somewhere? Your Tdi would have less power than standard.

Can you actually run an LPG/diesel vehicle on just diesel anyway?

[97discotdi]

If you run out of lpg it just reverts to standard specs diesel only. The figures I quoted was around Perth running so it would be fairly normal figures.

[redrover3]

Thought I would go and fill up here is the numbers 575k's 48.5l diesel 9l lpg. Should be accurate I use the same bowsers each time

Doesn't that work out at 10kms/l or 10l/100kms? That's not much better than standard although you do save about 65c/l with your 9l of lpg. How much extra power in this state of tune over standard 300tdi would you say?

[wozzlegummich]

Have you any idea if the EGT's went up or down?

[mcrover]

If my calculations or numbers are wrong please fell free to pick S**T as Im no maths expert

I separated the mileage for the reason of I wasnt interested in overall as LPG and Diesel are different prices and if I had to spend $4.50 to get close to the 8L/100km mark and recieve extra power to boot then I'd pay the extra $4.50.

The most I have ever used out of my 135lt tank was 130ltrs and then is was not wanting to start to drive to the bowser at work so working it out off say 9L/100km to be within a very broad tolerance, I should be then able to get 1444kms out of a tank of diesel, at 25% that it recomended I would need 32.5 ltr's of LPG which at 50c per lt would be $16.25.

At the moment on a very long run Im averaging the high 10s so we will say 11 to be on the safe side, gives me a range of around the 1100kms which is not bad and to get the extra 344km's from diesel alone would cost me at say $1.30/ltr (if not in cooberpedy) would cost nearly $50 if my maths are right (and I say that with a ? hanging over it, if Im wrong please feel free to point it out.

This means if the conversion was say about $4500, $2000 from the feds and $1000 from state govs makes a $1500 deficit which would be paid for in around 15000kms, less than a year for me and thats just the fuel saving nothing to do with the power increase.

Sorry about all the numbers, just thinking aloud and thought I would bore all you folks with it.

I now have to try and find the cash I think.

Has anyone had any trouble with insurance because of the power increase?

[Onethirty]

Thought I would go and fill up here is the numbers 575k's 48.5l diesel 9l lpg. Should be accurate I use the same bowsers each time


Thanks for that.

Baz

[Onethirty]

Hi Mcrover

Thanks for your comments. My interest is simply in increasing the range, the cost of fuel is less of a concern. The debate for me is what extracts the best range....

160 litres diesel + LPG (1,280 klm range @ 12.5/100), or
230 litres diesel, no LPG (1,840 klm range @ 12.5/100)

The way I am looking at this, putting aside the increase in power and potential cost savings, is that I need to extract an extra 560 klm out of the current diesel capacity with the addition of LPG otherwise the range is compromised versus what I can achieve from the additional diesel tank. That would require an improvement in consumption from 12.5/100 to 8.7/100; from research to date I think I would be lucky to get a 20% improvement.