Sometimes it takes a clever piece of technology or simply a particular engine to make you look at a car in a different light.

In the case of Fiat’s 500, the Italian firm’s Twinair two-cylinder petrol engine is a revelation. Delivering low emissions and fuel consumption with the energy and character of its pioneering predecessor, the two-pot 500 is a joy to drive.

At the other end of the performance spectrum is the 500C Abarth. Fans of the 500 will instantly be familiar with the Abarth’s go-faster connotations. In a nutshell, the tuning sub-brand offers affordable sporting thrills thanks to a range of well judged upgrades – not a million miles from Abarth’s roots.

The 500 Abarth isn’t an entirely new concept. You’ve been able to buy such a car for some time. What you haven’t been able until recently is buy one in convertible form. As if a 140bhp 500 wasn’t decedent enough, Fiat has cut the roof off.

Strictly speaking the 500C boasts a roll back roof, as the car retains the door frame structure of its tin-top relative. This fabric cover can be electrically wound back the car’s full length, includes a heated glass screen and offers near-hatchback levels of refinement when in place.

Somehow, even though a hatchback Abarth exists, it’s hard not to be charmed by the 500C model and its enhanced features. Certainly, with the roof down, it’s easier to hear the car’s feisty engine thanks in part to a pair of oversize exhaust pipes.

Those pipes join a modest but purposeful bodykit, chunky steering wheel, supportive sports seats, stylish alloy wheels and, crucially, retuned suspension settings.

Ah yes, the main reason for buying the 500C Abarth is its performance potential. And while it won’t worry the genuine hot hatchbacks occupying higher price points, the usable and accessible nature of this 500’s performance is not to be sneezed at.

The 1.4-litre turbo petrol motor might “only” produce 140bhp, but in a car this size that’s plenty. This rev-happy engine snarls its way around the rev counter, emitting a buzzy, impatient sound that’s highly addictive.

In an unusual move, the 500C Abarth comes with a semi-auto gearbox complete with steering wheel paddleshifters. It’s unusual for two reasons: such technology isn’t cheap yet Fiat has managed to position the car competitively, plus this technology always divides opinion.

Luddites will bemoan the lack of a clutch pedal – the 500’s gearbox is essentially a manual ‘box with the clutch action controlled electronically. In practice, leaving the car in Auto mode does require the driver to second-guess shift points and feather the throttle accordingly. And yes, that does take practice.

However, stick the car in manual mode and you have full control over gearchanges. This is by far a more rewarding experience, and it doesn’t take long before you’re zipping up and down the gears with those deliciously weighted paddles.

Better still is the car’s Sport mode, which adds more weight to the steering and sharpens the combined responses of the engine and gearbox.

Frankly, this can be left engaged all the time; far from turning the 500C into a temperamental trackday monster the sharper responses are welcome. Gearchanges feel crisper and there’s an audible change in the 500’s exhaust note, giving it a “big car” sound.

In short, the car is a hoot to drive. With no shortage of power, the 500C Abarth growls and screams its way from gear to gear, corner to corner. For a small car with sports suspension its ride is surprisingly supple, too. Grip that chunky steering wheel and, while more communication would be nice, there’s no question mark over the car’s ability to go where you point it.

On a basic level the 500C Abarth displays an edgy character that the regular, cute 500 lacks. Not everyone wants a bulging bodykit and a beefy exhaust, which is why so many regular 500s have found homes.

But that “‘edge”’ is precisely what the 500 needs to appeal to a section of the buying public seeking a fun, small car with genuine talent. It’s easy for car makers to bolt on go-faster bits to create the illusion of enhanced performance. Fiat has done a thorough job with this 500C – something Abarth fans can be proud of.

– IAIN DOOLEY