In technical terms, the engine of the latest variant of the Audi A2 to hit the road is related to the race engine that powered the Audi R8 to victory in last year's Le Mans 24-hour race.
No, Audi isn't fitting a version of its 610bhp 3.6-litre V8 to the little A2, but both cars do use the company's new direct injection petrol technology, which offers improved power and fuel consumption.
UK customers will have their first chance to sample this technology in the A2 in August, while a 2.0-litre version will become available in the Audi A4, replacing the 1.8T.
The inclusion of the new engine marks the beginning of an expansion of the A2 range. Although it has not yet been confirmed, we can expect a more powerful diesel engine - likely to be a 100bhp version of the 1.9 TDI - and there is also the slightest hint of a high performance S2 in the pipeline using the quattro all-wheel drive system.
The FSI engine uses similar principles to diesel engines and operates in one of two modes, depending on the load it is under and the throttle position.
When more power is required, the engine uses more fuel - like a conventional engine - although it is burnt more efficiently via direct injection into the combustion chambers, thereby achieving lower fuel consumption.
However, under part load the FSI uses less fuel than a conventional engine and cuts back heat loss.
In the past, manufacturers have had difficulty with direct injection petrol engines emitting higher levels of NOx (nitrous oxides) than conventional petrol engines. But the FSI system works in conjunction with an exhaust gas recirculation system which diverts up to 35% of exhaust gasses back into the combustion chamber, plus a NOx storage converter.
It means the 1.6 FSI complies with Euro IV emissions legislation, which is particularly tough on NOx outputs.
The bonus for company car drivers will be a lower CO2 emissions rating than the A2 1.4. Although the price premium for the FSI might mean slightly higher benefit-in-kind tax bills, its emissions of 142g/km against 146g/km for the 1.4 promises the lowest BIK tax band beyond the scope of the current rules.
Audi expects the 1.6 FSI to boost its UK sales by 20% from 5,000 to 6,000 units, although some FSI customers will simply migrate from existing A2s.
The company has also been surprised by the number of A2s that have been chosen by customers with several thousand pounds worth of options fitted.
Unlike the Mercedes-Benz A-class, which is sold into rental in the UK as well as other fleet and retail channels, it seems the Audi A2 holds a unique position in the prestige market place, and a recent price cut for SE models and further developments in the pipeline are set to broaden its appeal.
Behind the wheel
ALTHOUGH the A2 has been on sale in the UK for the past 18 months it is still a rare sight and its unusual and unmistakable appearance makes its design seem 'cutting edge'.
Its lightweight aluminium-bodied construction adds to the space-age feel of the car, while the styling cues borrow heavily from other models in the range. Despite its diminutive size, there is a lot of A4 and TT in the A2's appearance.
New for the FSI and in line with a minor facelift across the A2 range is a longer rear spoiler, revised suspension settings and the introduction of a Sport model with the option of imposing 17-inch wheels.
The dashboard layout is scaled-down A4 and anyone who has driven an Audi will be at home inside the A2. The good thing about the A2 is that the quality of the interior is no different from the high standards set in the A4 and A6, and is better than the Mercedes-Benz A-class.
The new engine is quiet and refined around town but begins to sound rather fruity when swifter progress is needed. Revving the 1.6-litre FSI engine to the red line offers the rare aural pleasure that is usually reserved for Honda VTECs and Alfa Twin Sparks.
The light body means the car feels a bit livelier than you would expect for 1.6 litres, and the A2 has always had sharp handling despite being tall. Changes to the suspension mean the ride feels more settled over bumpy roads than before. Although it still isn't perfect, the improvement is noticeable.
So what's the catch? Well, the FSI technology only works at optimum efficiency when used in conjunction with high-octane fuel such as super unleaded or Shell Optimax.
Audi says using ordinary unleaded will not affect the emissions, fuel consumption or power output, but maximum torque will be lower. It means the price premium for the more expensive fuel to some extent negates the effect of the more efficient engine.
But with the increased fuel tank and better fuel consumption than the 1.4 petrol engine, the new FSI should make far fewer stops for fuel (with an effective touring range of more than 400 miles) and should be less expensive to run.
THE A2 FSI means everyone is a winner. Although it is more expensive than the standard car, you get better performance and economy and with the revisions that are being implemented across the range, the A2 has become more satisfying to drive.