Launched in 1966, the GTA (with ‘A’ denoting Alleggerita, meaning lightened) served as the official competition variant of the Giulia Sprint GT, available in both road and race configurations. The racing version fell under the purview of Alfa Romeo’s Autodelta competitions department, initially an independent company founded by Carlo Chiti and Ludovico Chizzola in 1961 and later absorbed by Alfa Romeo.
While visually akin to the road-going Sprint GT, the GTA distinguished itself through aluminum body panels, Plexiglas side and rear windows, and lighter interior components. Consequently, the GTA shed around 200 kilograms compared to the standard steel-bodied model. The classic twin-cam 1,570cc four underwent significant modifications for the GTA, including a reduction in valve angle from 90 to 80 degrees and an increase in valve sizes. The engine, adapted for twin-plug ignition due to the absence of space for a central spark plug, produced 115bhp in road trim and up to 170 horsepower in race tune.
The GTA debuted in racing at Monza on March 20, 1966, securing victory in the Jolly Club Four-Hour Race with drivers Andrea de Adamich and Teodoro Zeccoli. Subsequently, Autodelta-prepared GTAs dominated, clinching the European Touring Car Championship from 1966 to 1968. The arrival of the GTA 1300 Junior in 1968 disrupted the Mini Cooper’s dominance in the Championship’s 1,300cc class. This model featured a unique engine, combining the Giulia’s 78mm bore with a 67.5mm-stroke crankshaft. With the GTA’s twin-plug head and a rev range exceeding 9,000rpm, the engine produced over 150bhp. Production of the GTA 1300 Junior ceased in 1975, with just over 400 units crafted.