In 1992, the Alfa Romeo 155 GTA clinched the Italian Superturismo Championship and inspired a new challenge: preparing a car to enter the DTM in Germany.
In the 1990s the Deutsche Tourenwagen Meisterschaft (German Touring Car Championship or DTM), which always generated great public interest, had very lenient tuning rules that permitted teams to enter radically modified versions of production models. Among the few things that could not be modified were the engine displacement and the material used for the engine block. A new rule introduced in 1993 for the D1 class also limited engines to a maximum of six cylinders and 2.5 litres capacity.
Under the stewardship of Giorgio Pianta, the Alfa Corse team designed and built a true competition thoroughbred based on the 155 production model's 2.5 litre V6 engine with monobloc construction and aluminium cylinder head. Everything else was changed and the 155 2.5 V6 TI was born.
The engine was turned to a longitudinal position to give the vehicle four-wheel drive. A new magnesium crankcase housed the six-speed gearbox, front differential and central epicyclic differential (drive torque distribution was 33% to the front and 67% to the rear). The car had titanium inlet valves, dry-sump lubrication and an electronic system that communicated with the two three-way catalytic converters to control emissions. The engine weighed only 110 kg and produced 420 hp at 11,800 rpm. Thanks partly to its carbon fibre body, the car weighed just 1040 kg.
A winning debut in rainy conditions at Zolder set the tone for a dominant campaign by Nicola Larini, who won almost half the races on the way to taking the title.
The choice of four-wheel drive turned out to be a winning decision, judging by the clear superiority of the Alfa Romeos in a rain-soaked first round at Zolder: Larini won ahead of Christian Danner, who was driving a 155 for the Schübel team. Round 2 produced a 1-2-3 finish for Larini, Danner and Nannini, with Alessandro Nannini coming from behind to snatch the third podium place.
Nicola Larini won again at Nürburgring (three times), Wunstorf, Norisring (twice), Donington (non-championship event), Diepholz and Singen. Helped by other outstanding podium performances along the way, Larini ended the season with 261 points ahead of Roland Asch on 206 with the AMG-Mercedes 190E. But the 155 took another three victories, with Nannini topping the podium in the two final rounds at Hockenheim, while Danner won one round at Donington in a non-championship event. Giorgio Francia, a legendary driver for the Alfa Romeo stable, came second at Wunstorf, twice finished runner-up to Nannini at Hockenheim and took third place at Singen. In total, the 155 2.5 V6 TI won 12 out of 20 races in the 1993 Deutsche Tourenwagen Meisterschaft.
