Difference in LPG mix.

[tngster]

I just converted my 1996 Vienta 3vzfe to run on the sprintgas lpg system. The installer told me to pump BP lpg rather than shell lpg because of the propane/butane mix. I'm still in the midst of calculating the mileage I get on LPG. I'm hoping that someone can shed some light on the differences between different brands of LPG. Installer told me that supagas is the best LPG to use. Cheers.

[Hotbreeze]

I cant tell you which brand is better but I can tell you that the propane/butane mix will determine fuel economy. But only if your air fuel ratio is varied to suit.

The reason is that butane has more energy per litre than propane because it has a higher density, its molecule is C4H10 where propane is C3H8.

The reason they mix it is because of their different boiling points, butane boils at -1C and propane at -42C so depending on where you live will determine how much propane is added to stop the gas from freezing in the gas convertor, people will tell you how much of a pain that can be in places where it drops below freezing quite regularly in winter.

Hope this helps.

[Kinezo]

I cant tell the difference. Had a 1mz-fe Camry on gas (Apollo throttle intake system) and have use all brands. They're all the same.

Now I am driving an Aurion with Orbital Liquid Injection and cannot tell a difference again. Ive used BP/Shell/Independents/Mobil etc...

Whatever is cheapest :D

[Hotbreeze]

When I said depending on where you live I mean the difference between Darwin and say Mt Hotham.