Ben,
It may be closer in terms of costs when touring - not sure on that - depends on capacity and type of vehicle, weight, engine + other assorted sundries. All I will say is when we toured up to Qld Xmas 2010 from Sydney - I was getting close to 300k's on an 80 ltr tank of LPG which cost me about $50 to fill up. The cost of LPG locally where I am right now is nowhere near $1.50 ... more like 75c/Ltr I think. On the Nulla, it will probably be pricier - but traveling the Pacific highway and other major hwy servo's would still have pretty cheap LPG - nowhere near $1.
So depending on capacity etc + cost of fuel I still think the LPG comes out in front - the range of diesel would be better ( fewer stops ) but I think my costs would still be lower in the long run. My truck is dual fuel also so I can flick to petrol should I need to in a touring situation and also carry additional fuel. It's all good fun and I merely put it out there as another consideration when you consider the costs of a conversion ...
P.S You ever chat to any of the old Stumpers?
Tiki.
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