This 500 TwinAir uses a 2 cylinder turbocharged engine with is 23% shorter and 10% lighter than a 4cylinder engine that has similar performance figures. It is also very economical as it would only consume 4.0-4.1ltrs/100km while emitting only 92g/km of carbon when matched with the Dualogic robotized gearbox and 95g/km of carbon for the manual version. This figure is about 30% less CO2 emissions that a 4cylinder engine of similar performance.
It makes 84bhp and has a maximum of 145Nm of torque when used in 'Normal' mode and 100Nm in 'ECO' mode. This two modes have different engine maping as well as different steering feel. The class leading emissions is due to the small displacement (900cc), good low end torque (imagine 450cc per cylinder instead of, say 300cc for a 3 cylinder engine big bore engines make better torque), the Start&Stop engine idle system and Gear Shift Indicator (for the driver to see that he is in the most efficient gear).
All of this technology in a small engine still allows the 500 TwinAir reach 100km/h from rest in 11seconds and a very highway able 173km/h. But it is of my opinion that a 2 cylinder engine can be pretty thrummy as it is inherently unbalanced. My experiences with small twos are from those BMW boxer twins, Ducatti V-twins, Harley Davidsons and the old 500 itself tell me that it does shake, rattle and roll a little more than even a 3 cylinder (like the Perodua Viva). Maybe the turbo will mask some of the vibrations when it spins but it would never beat the refinement of a decent 4 cylinder engine. It may sound a little unique but an in-line 'two' will never sound like a Ducati V or a Boxer twin.
But since this car is meant for countries where the tax of a vehicle is counted on the amount of emissions it releases, the 500TwinAir may not reach our shores as local tax does not count carbon emissions, only engine capacity. So expect no change in the Fiat 500 line-up even regionally. Furthermore, this Fiat costs as much as a 1.4liter turbodiesel, due to its extra technology items like the stop-start function and the original costs of designing an building a new engine from scratch. But maybe you do save on servicing costs as the small size of the engine means 2 less sparkplugs and less engine oil to buy too.
Anyway, this little Fiat shows us how much manufacturers are going out of its way to find new methods to cut carbon emissions. New methods here also mean revisiting the past and coming out with a new version of it. A 2 cylinder Fiat 500 was first launched way back in the 1950s, and now its back again. A full circle.
Expect Fiat to launch a Hybrid version as well as a non-turbocharged version and also a more powerful 104bhp version.