Whenever someone posts up their rolling road results on MINI2, you can almost guarantee an ensuing debate about dyno graphs, drivetrain loss, airflow, temperature, humidity and just about anything else that can affect the outcome and interpretation of such tests. The conclusion generally being that they’re a decent measure of before and after modification power, or for a bit of fun and one upmanship, but not much beyond that.

With that in mind it was interesting to read that Stockholm based Rototest have collated figures from more than 550 engine tests performed using their own unique dynamometer which bolts directly onto the wheel hub in a handy to use web format. And at the same time drawn the conclusion that the average vehicle only achieves around 90% of it’s stated output.

However, according to Rototest (and of interest to us), manufacturers providing more power than their official claims include Mazda, VW, Skoda and MINI. While three of the top five models had forced induction engines.

“It’s very difficult to tell exactly why they do well, but maybe the car we tested is better built or that the manufacturer under-quotes the power for marketing reasons. They are also press cars and there is a chance they are in, let us say, peak condition,”

Explains company boss Christian Engstrom. Hmm, not implying the motor manufacturers tweak their press cars for favourable review there, are you Mr Engstrom? Shocking.

Via their website you may view all performance graphs, and the specific results for the MINI Cooper S (Pre-facelift), MINI Cooper S (facelift), MINI Cooper S (2nd Gen) and MINI Cooper (pre-facelift). Based on resent conversation, the results may surprise some.