Some fuel economy-related news, and how diesel comes up trumps again. Over in the UK, the annual 2012 ALD Automotive / Shell FuelSave MPG Marathon held last weekend saw a Ford Fiesta ECOnetic 1.6 TDCi clocking up an amazing 108.78 mpg over a 370-mile route involving tough, real-world driving in challenging weather conditions.

That’s 38.50 km per litre (on an Imperial gallon measurement) over a 595 km course, or 2.59 litres per 100 km, for you metric-minded folk.

The Fiesta was coaxed round the course by former rally drivers Andy Dawson and Andrew Marriott, though they were not the first team to break the magic 100 mpg barrier on the day. Earlier, three-times former winner Mick Linford brought home a Kia Rio 1.1 CRDi eco with a 102.21 mpg (36.17 km per litre) reading, the first time in the history of the event that a vehicle had crossed the 100 mpg mark.

When it came to refueling to measure, the AA fuel marshals couldn’t get more than 3.4 gallons (15.45 litres) of Shell FuelSave diesel into Dawson’s Fiesta, sealing a remarkable win for the Ford-backed team. Third place went to another diesel job, a Peugeot 208 e-HDi clocking 93.4 mpg (33.05 km per litre).

The MPG Marathon – organised by UK’s Fleet World magazine – is designed to be a “real world” test that demonstrates the benefits to the motorist’s wallet by employing simple, smarter driving techniques. Only two of the 20 cars competing in the event failed to beat the manufacturer’s official Combined MPG figure, event organisers said.

Of course, temper the imagination that this is nothing more than a benchmark. “Manufacturers have done a tremendous job in improving the fuel efficiency of all new cars and vans, but motorists should see their published fuel consumption figures as a target to beat, not the maximum achievable,” said event organiser Ross Durkin.