Most frugal car in the real world? Autocar finds out with a race...

Manufacturers make big claims about their fuel economy figures. Occasionally, even these claims can be bettered, as Toyota's now closed blog for the iQ managed back in January, extracting 72mpg when Toyota themselves only claimed 65mpg. Often though, real-world driving prevents us from extracting the optimum economy from our cars.

Autocar's test then perhaps sheds a little more relevance on achieving high miles to the gallon. Armed with a Ford Fiesta Econetic, a Vauxhall Corsa Ecoflex, an Insight, a Prius, a BMW 116d and a Smart ForTwo CDi, they each hit the track at Bruntingthorpe with a single litre of fuel and a driver trying to achieve as many miles in the hour as possible. By working to distance rather than outright economy, it avoided the whole race becoming a slow eco-trundle.

The most efficient at the end of the hour? Ford's Fiesta Econetic. It achieved almost sixty miles at the hands of Matt Prior, equivalent - unsurprisingly - to roughly 60mpg. A little way short of Ford's 76mpg combined figure perhaps, but much more representative of what drivers can expect in their daily grind, and a long way from shabby.

The other cars in the test all managed to average around 55mpg, including the diminutive Smart despite being driven pedal-to-the-metal until it spluttered to a halt after 53 minutes.

The full story can be found in the 30th September issue of Autocar, out now. Alternatively, you can watch the video: