I've been asked a few times about running costs, so here goes:
Done my first work run on LPG, still need to do a little tweaking with the tank, it needs to be rotated bit further as I only got 68L in 90L tank, I want to get it up to 72/73L
My usual commute on petrol would cost me approx £26/27 each day, doing 150 miles and returning approx 30mpg, which works out at 17.3 pence per mile.
With LPG i am actually driving a further 20 miles to start with, going to a cheaper garage down the road, as its 68.9p a litre at BP around the corner, but 58.9p 10 miles down he road!

Once everything is settled i will be using Asda at High Wycombe were its 54.9p litre.
But even doing 20 miles further, i did 168 miles, and used 31.06L of gas, which works out at 10.8 pence a mile, roughly 25mpg. Which gives me an effective mpg of
at least 50 mpg

It cost £18 for the gas, so already saving £9 per day, reckon once i start using the cheapo station on my commute and not doing an extra 20 miles, i should be on target to save £10
per day!
As is considerably less than half price at Asda, should nudge effective 55mpg

Range wise, with 168 miles done, only used just over 1/3 of a tank. So once rotated and more fuel in, i expect range to be approx 350 miles.
One for the gas experts, would reducing gas pressure help mpg? Its running about 1.10 Bar currently.
