From a 1-2-3 finish in the 1000 km of Monza in 1974, to the 1975 world sportscar crown and victory in the Targa Florio: the Alfa Romeo 33 TT 12 confirmed its supremacy by winning seven out of eight world title races.
The 33 project was constantly evolving. After increasing the displacement of the V8 engine, in 1970 Alfa Romeo built a new aluminium alloytubular chassis (hence the TT denomination, which stands for ‘Telaio Tubolare’) to make the performance of the V8 more effective. In 1973, a new tubular steel chassis was designed to accommodate the flat-12 engine, launching a motor racing career that would culminate in the 33 TT 12 winning the World Sportscar Championship two years later.
The 2995 cc flat-12 engine had dual overhead camshafts per bank with cascade gears commanding four valves per cylinder, indirect Lucas electronic injection, Dinoplex electronic ignition and dry sump lubrication with oil cooler. The engine initially developed470 hp at 1100 rpm but this was upgraded to 500 hp at 11500 rpm in 1975 for maximum speed, depending on the final ratio, giving the car a top speed of over 330 km/h.
A total of six 33 TT 12 specimens were produced between 1973 and 1975.
Pole position and a 1-2-3 in the 1000 km of Monza: Andretti-Merzario finished ahead of Ickx-Stommelen and De Adamich-Facetti, all driving Alfa Romeo 33 TT 12 cars. It was the first in a long series of victories that would lead to the 1975 world sportscar title.
In 1975 came the long-awaited victory in the World Sportscar Championship, with the 33 TT 12 winning seven out of eight races. The cars were managed by Autodelta and competed in the colours of the Willi Kauhsen Racing Team.
Arturo Merzario and Jacques Lafitte dominated in Dijon, Monza and Nürburgring; while Henri Pescarolo and Derek Bell won at Spa, Zeltweg and Watkins Glen. The seventh victory was at Pergusa, where Merzario and partner Jochen Mass took top spot on the podium.
In addition to the seven victories counting towards the World Sportscar Championship, the 33 TT 12 also triumphed in the Targa Florio, which for the first year was valid only for the Italian Championship and no longer for the world title. Local idol and Targa Florio specialist NinoVaccarella partnered tireless Autodelta stalwart Arturo Merzario to victory on 20 July 1975, on the short Piccolo Madonie circuit in Sicily.
Watch the video of Arturo Merzario driving the Alfa Romeo 33 TT 12 on the streets of the Targa Florio.
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