It’s the Italian manufacturer’s new 159 GTA – and with a potent 400bhp engine coupled to a four-wheel-drive transmission, it’s gunning for the Audi RS4. Spied here testing at the Nürburgring circuit in Germany, the GTA is being put through its paces ahead of a world debut at the Frankfurt Motor Show in September.

Whatever the powerplant, expect a 0-60mph time of five seconds and a top speed in excess of 155mph. There will be plenty of grip, too, thanks to Alfa’s Q4 four-wheel-drive system

Alfa is currently considering two engines, each with similar outputs, for the super-saloon: either a twin-turbo version of the 159’s 3.2-litre V6 or a 4.3-litre normally aspirated V8 developed from the unit in Maserati’s GranTurismo coupé.

Our sources indicate that the V8 is the preferred choice because it produces less torque than the V6 turbo, allowing unmodified versions of Alfa’s existing gearboxes to be used. That means the GTA should be available with six-speed manual, auto and Selespeed clutchless manual set-ups.

Whatever the powerplant, expect a 0-60mph time of five seconds and a top speed in excess of 155mph. There will be plenty of grip, too, thanks to Alfa’s Q4 four-wheel-drive system. The 159 GTA will also look the part, with gaping air intakes – concealed here by black plastic – and extended arches. As well as the saloon, a Sportwagon estate is expected. Both models will cost in excess of £40,000 and go on sale in the UK in 2008. If you can’t wait until then, though, Alfa has announced the arrival of the 159 TI – a sporty-looking new trim level which features a unique bodykit, lowered suspension and 19-inch alloys.