The 147 was designed by Walter de'Silva and Wolfgang Egger. The 147 received considerable praise for its styling on launch, later it was awarded with some styling awards. The entire 147 range was revamped in 2004, with the exterior styling changed considerably to be more reminiscent of the new 159 and Brera models, most notably for its more aggressive look. The 147 achieved a drag coefficient (Cd) of 0.32.
The 147 was facelifted in the end of 2004: new front grille, new headlights, new rear lights and interior was updated on all models besides the GTA version. Also new more powerful diesel engine arrived and suspension was also tweaked. In 2006 was launched 147 1.9 JTD Q2 version, which features a front Torsen limited slip differential. Alfa Romeo presented a new limited edition 147 called Ducati Corse In 2007 Bologna Motor Show. The car is equipped with 170PS (168hp/125kW) JTD diesel engine and Q2, a front Torsen limited slip differential.
The 147 is scheduled to be superseded by the new Alfa 149 in 2009.
The hot hatch 147 GTA model was launched in 2002. The GTA used a 3.2 V6 engine, produced 250PS (247hp/184kW) and could achieve a top speed of 246km/h (153mph). It has a widened body (15mm at each side) to accommodate the 225/45R17 tyres. Earlier models have 6-speed manual transmissions; later models use Selespeed.
Its competitors in Europe include the Audi S3, BMW 130i, Volkswagen Golf R32 and the Renault Megane RS.
London-based after-market tuner Autodelta has produced a "bored out" version of the GTA sporting a 3.7-litre V6, producing 328bhp (245kW), and a split-axle differential gear for the front wheels. Autodelta has made also a Rotrex supercharged version producing 400bhp (300kW).
The handling of 147 was praised in some reviews, in spite of criticism regarding the light (sensitive) steering, which makes some drivers feel less involved. However, light steering does help during parking maneuvers. Other criticisms of the 147 included a cumbersome gearshift, unsupportive seats and the lack of interior space compared to its rivals. The car became well-known for its engine note, which is unusually mellifluous for a car of its class. The 147 suffers from poor resale value in Great Britain. The 147 GTA and 147 Autodelta GTA have been road tested by Jeremy Clarkson, and featured on television show Top Gear with a power-lap around the track by The Stig. In his review of Autodelta 147 GTA car for The Sunday Times, Clarkson described the acceleration as "...Ferrari throttle? Forget it. When you stamp on the accelerator it’s like you’ve hit the Millennium Falcon’s hyperdrive. Suddenly all the stars are fluorescent tubes. ..." and the handling as "....A corner was coming. And then it was a distant speck in my rear-view mirror. I vaguely remember turning the wheel and I have a dim recollection of being astounded by the grip . . . and then the moment was gone. No, really, the damn thing is a barnacle....".