HI. I have been running a Mini Cooper SD Coupe (2102 with 2k to 7k miles) for the past 5 months. I have alternated the use of 6 fuels to see if any brand makes a difference to fuel consumption - it does! I do the same type of driving every week, and refuel to the 'brim' for consistency. The mileometer checked against a motorway 'measured mile', and found to be dead accurate. The on board computer is very good also.
The results, each over a tank full of around 375 miles: BP & BP Ultimate: 47.68 Shell & Shell V Power: 49.0 Esso: 51.57 Texaco: 52.54
The worst performing fuel were the most expensive, ie Shell V Power and BP Ultimate. The best was Texaco, every time, you could immediately see the improvement on the computer readout.
Quite surprising variation, but the results were consistent, and each tank full was filled randomly, so not weather/conditions affected etc.
Have you or anyone else noticed these quite significant variations in consumption based on type of fuel used? I know that you favour V Power but it did nothing in the Mini apart from cost more!
The car is now sold and I intend to do the same in a VW Golf GTD, which immediately seems more fuel efficient than the Mini, in spite of the manufacturers fuel figures which suggest the opposite might be the case?