The 'Ultra' tag will be familiar to fans of endurance motor racing, seen since 2010 on Audi's Le Mans-winning race cars.

It hasn't yet featured on an Audi production car though, up until now--and as you'd expect, it's Audi's most fuel-efficient production car ever.

The Audi A3 1.6 TDI Ultra uses a familiar engine to European buyers and unfamiliar to their U.S. counterparts--as the Ultra won't be hitting American streets.

The 1.6 TDI already appears in several other Volkswagen group models in various states of tune. In the Ultra, it's good for 73.5 miles per gallon--albeit recorded on the European combined fuel consumption cycle.

That's identical to the latest Volkswagen Golf Bluemotion also sold in Europe, which uses the same 110 horsepower, four-cylinder 1.6-liter turbodiesel engine.

Performance is also similar, and highlights the advancements made in cars of this type over the last few years--despite its modest capacity and efficiency-biased setup, the benchmark 0-62 mph sprint still takes just 10.5 seconds and top speed is an aero-assisted 124 mph.

It should be a good long-distance car too, with a full tank range of over 930 miles.

A set of S line sill extensions from the sportier A3 variants helps aerodynamics, as does a ride height reduced by 0.59 inches. Low rolling resistance 205/55 R16 tires are fitted, while the A3's body weighs a respectable 2,656 pounds.

This most miserly of A3s is the first car to wear Audi's Ultra badge, which the German automaker says is reserved for cars which best express "the brand’s all-encompassing commitment to systematic sustainability concerning production and products".

Odd then that Audi isn't using it on the recently-unveiled A3 g-tron natural gas car and A3 e-tron plug-in hybrid--but Audi's 'tron' naming already stands for greener driving, and is itself no stranger to Audi's Le Mans-dominating racers.


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