Group Captain Smudger

This formula, devised by a former oil engineer (BP I think), involves amongst other things the official manufacturers' consumption figures for urban, 56 and 75mph to give a figure that your vehicle should be obtaining. It takes into account engine wear and tear. The Impreza Turbo (old model) comes out at 21.6 (my 2000 figures: low 20.9;hi 29.7; town 22.0; mean ave. 24.6). The point is made that if you are not achieving this figure then you are either heavy on the brakes/accelerator or your engine is sh4gged. If you wish to know what other vehicles achieve then I would need the official figures to work it out.