2010 TG Awards: Engine of the Year

Here's one for petrolheads. In the face of cars motivated by diesel, electricity or hydrogen, Fiat presents us with this little bundle of energy, charm and downright saintliness to prove that our good old friend the gasoline engine is still alive and very much kicking.

Words: Paul Horrell

This article was originally published in the Awards issue of Top Gear magazine

The 500 TwinAir is quiet, torquey and far more sprightly than a car with 84bhp and 875cc has any right to be. It chatters softly but cheerily as it goes about its business, the sound sweetening and the vibrations magically disappearing as it climbs toward the red line. But if you keep the revs down and drive it on the bass-heavy torque curve, the fuel gauge seems to jam, as evidenced by the 95g/km CO2 figure.

To match the TwinAir's performance-and-economy combo, you'd need a four-cylinder diesel, which would be bigger, heavier, noisier, dearer and less fun. And the TwinAir is holding something in reserve. A 105bhp version will be along shortly.

These miracles flow from the Fiat Group's patent MultiAir system. High-speed electro-hydraulic actuators are inserted between the cams and inlet valves, controlling their opening and closing timing and lift. It gives far more wide-ranging control than previous efforts like VVT or VTEC or Valvetronic ever could.

MultiAir arrived last year in the 1.4-litre four in the Alfa MiTo, but that was a new head on an existing block. By designing a brand-new engine around MultiAir, Fiat's now fully pressed home the advantages.