A 55 Polo 1.4 litre is 75bhp and weighs in at around 1.2tonnes whereas the the ForFour is 1.1 litre and 75bhp and weighs in at 0.9tonnes... hmm do the math.
The power to weight ratio (bhp/tonne) figures are key to the ForFour NOT the factual bhp figures, cos they undermine the car.
A colleague at work has a 2010 Mazda 2 which is 1.3 and puts out 85bhp returns about 45mpg max and an avg. of 40mpg... a 5y/o ForFour can trounce those figuresv!! Yes the ForFour tech is getting superceded by charged motors but for normally aspirated tech they still are leaps and bounds ahead !
Oh and a bog std 55reg Golf GTi and ForFour Brabus have near equivalent bhp/tonne...