Alfa Romeo 33 Stradale

The Alfa Romeo 33 Stradale is an extremely rare road car built by Alfa Romeo of Italy. Only 18 are reported to have been made.

The Stradale, first built in 1967, was based on the Autodelta Alfa Romeo T33 racing car. The car, designed by Franco Scaglione, and built by Carrozzeria Marazzi, made its debut at the 1967 Turin Motorshow.

Built in an attempt by Alfa to make some of its racing technology available to the public, it was the most expensive automobile for sale to the public in 1968 at US$17,000.

The Stradale is believed to be the first production vehicle to feature dihedral doors, also known as butterfly doors. Other vehicles which feature doors of this nature include the Toyota Sera, McLaren F1, Ferrari Enzo and the Saleen S7. The Stradale also features windows which seamlessly curve upward into the 'roof' of the vehicle.

The race-bred engine bore no relation to the mass-produced units in Alfa's more mainstream vehicles. Race engineer Carlo Chiti designed an oversquare (79mm bore x 52mm stroke) 2.0 liter V8 that featured Spica mechanical fuel injection, four ignition coils and 16 spark plugs. The engine used four chain-driven camshafts to operate the valve train and had a rev-limit of 10,000 RPM - unprecedented in a piston-engined roadcar of similar displacement – then or now. For comparison, the modern 2.0 liter Honda S2000 revs to 9,000 RPM. As a result, the Alfa's engine produced 250 horsepower (10 more than the Honda). In another break from convention, Alfa used a six-speed transaxle gear box by Valerio Colotti.

The car's performance was similarly unprecedented. The car took only six seconds to reach 60mph from a standing start.