Taking weight out of a modern car can be tricky: Crash regulations have necessitated heavier structures, emissions laws have forced additional complexity into vehicles, and amenities have added dozens of electronic control units and untold miles of cable. Many automakers, however, are now experimenting with shedding pounds as a means to maintain performance despite the current trend toward engine downsizing. To illustrate the potential of this approach, Audi engineers set out to create an A5 2.0T that weighs 500 pounds less than a 3400-pound Euro-spec A5 V-6 model (U.S. versions weigh roughly 200 to 300 pounds more due to options and higher levels of standard equipment). The result is an A5 coupe that, according to Audi, tips the scales at a svelte 2888 pounds despite retaining the 2.0-liter’s heavy iron block.
Audi let us compare a stock A5 3.2 FSI, equipped with the 265-hp V-6, against the lightweight concept with the 2.0-liter engine dialed back from 258 pound-feet of torque to deliver the same 243 as the V-6. We can attest to the fact that a 500-plus-pound reduction makes for a stunning dynamic improvement. Turn-in becomes more agile, the car can be tossed around with ease, and the 211-hp engine feels far stronger than its numbers suggest.
A regular A5 3.2 FSI seems downright clumsy in comparison. Audi claims the lightweight concept is 0.3 second quicker to 60 mph than the V-6. In our testing, the A5 V-6 ran from zero to 60 mph in 5.8 seconds, so we expect the lightweight concept to hit 60 mph in 5.5 seconds, a 0.7-second improvement over a standard A5 2.0T.
Audi originally intended the concept to emulate the performance of the V-8–powered, 354-hp S5, but, despite the weight loss, the concept still can’t match the S5’s acceleration. We understand that a second concept is currently being built—and we wouldn’t be surprised if this one was equipped with the 265-hp, 2.0-liter turbo four from the TTS. With that much power, the four-cylinder lightweight just might be able to trounce the S5’s V-8.
Most “efficiency” concepts make us dread the future; this one gives us hope.