Making further use of its aluminium Audi Space Frame (ASF) concept, Audi has presented a special A5 Coupe prototype that has sheds 110kg or 240 pounds over the standard steel-bodied production car with a 2.0-liter TFSI. This was achieved by swapping steel for advanced aluminium and carbon fibre construction. Audi says that the aluminium A5 prototype has a kerb weight of 1,310kg (2,888 lbs), versus a total of 1,420kg (3,130 lbs) for the equivalent steel-bodied series production model.

This means that with the 211HP 2.0-litre turbocharged FSI engine, the A5 Prototype achieves a power-to-weight ratio of 161HP per tonne. For comparison, the 'standard' A5 Coupe 3.2 FSI V6 quattro with 265HP that weighs in at 1,540kg, is only slightly better at 172PS per tonne.

"The lightweight design of the test car not only enables a smaller engine to supplement a larger one with no impact on performance and gains in economy and emissions, but also has a knock-on effect on ancillaries such as the brakes and transmission, which can also be reduced in size and weight," said Audi.

"It also enables the car to change direction noticeably more keenly and nimbly and, thanks to the reduction in unsprung weight, to ride with even more refinement," the company added.

Even though the aluminium A5 Coupe Prototype isn't intended to make production, we suspect that the next generation model will most likely benefit from this lightweight concept.