Ive been experimenting this thing with an old cavalier td Im using for work, mix it 50 / 50 and you cant even tell the difference apart from a very slight change in scent from the rear,
I then thought fuck it ill go all the way,
Last week there was about a gallon of diesel left in there and i filled it with 50 litres of fresh rape seed oil. I read somewhere that rapeseed and sunflower oil are better as they are thinner,

Well im happy to report that even coming out of work at 4 in the morning it never failed to start once and although the tickover was a little low for 30 seconds it worked just fine, I think it did notice only a very slight perforance drop but this was in temperatures of minus 2, Ive now covered 600 miles so far and were still going strong.
Will think about changing the fuel filter soon though as People reckon veg oil cleans the system of all the crap and can block the filter, Or maybe this is when using Biodiesel
I think I going to carry on using the oil as Because of the fuel situation at the moment I saving about £30 a week and that makes a difference.

P.s my local Lidl have been selling Rape oil at 49p per litre at the moment

get some funny looks when ive got a trolley full of oil lol, Said i was in catering and the supplier failed to deliver that week lol