Away from some of the bigger green reveals at the 2012 Detroit Auto Show, Chevrolet launched two sporty concept cars aimed at younger buyers.

The rear-drive Code 130R and Tru 140S concepts caught our attention not just because of their striking looks, but also their fuel-efficient drivetrains.

Both utilize a 150-horsepower, 1.4-liter, turbocharged four cylinder engine, similar to the one you'll find in the 2013 Chevrolet Sonic RS. This would come with a six-speed manual or six-speed automatic transmission.

We already know the 1.4-liter turbo can be an economical engine in the Sonic, but here is also uses an eAssist hybrid drive system, that offers stop-start technology, brake energy regeneration and electric acceleration assistance.

This points towards a 40mpg highway rating, but also impressive economy in city driving.

High Gear Media colleague Joel Feder took a look around the rakish Tru 140S concept at Detroit. Designed as a competitor for the Hyundai Veloster and Volkswagen's "forbidden fruit" Scirocco it uses front-wheel drive and if produced, would cost in the low $20,000 range.

Both cars are an attempt by Chevrolet to fully aim a car at under-30s, or "Millenials" - something they see no other carmaker really making an effort to do.

Chevrolet clearly understands that young buyers cannot be tempted solely by economy. By making some stunning, affordable concept cars, it can tempt in young buyers with what they want, while improving fuel efficiency.