be detuned. Iso Rivolta Bizzarrini worked since 1964 for Iso Rivolta and developed three models: Iso Rivolta GT, Iso Grifo both A3L and A3C versions. His work was to develop a pressed steel frame chassis for Iso cars. Renzo Rivolta hired him as consultant to the Iso Gordon GT project which became the Iso Rivolta GT. The Iso Gordon GT prototype was developed from the Gordon-Keeble. The Gordon Keeble GT was designed in 1960 by Giorgetto Giugiaro. Bizzarrini tested the car and was impressed by the powerful V8 Corvette engine and the rear De Dion tube suspension used for the GT. The Iso Rivolta GT was a Giugiaro-designed four-seater with beautiful body, speed, comfort and handling, and was a successful car for Iso, with 799 units sold. Powered by a Chevrolet Corvette V8 engine with a classic De Dion rear suspension design with pressed steel monocoque bodywork over pressed steel frame chassis. Unveiled to the press in 1963, production continued until 1970. Iso Grifo The Iso Grifo A3L was a super coupé, the L coming from Lusso. The result of Giugiaro and Bizzarrini working together, it was based on a shortened Iso Rivolta GT chassis and was debuted at the 1963 Turin show. The Grifo epitomised the 1960s Italian style with its handsome low and wide handmade bodywork. It was the fastest production car tested by Autocar Magazine in 1966 with a top speed of . Later versions of the Grifo were powered by a big block Chevrolet Corvette engine. These 90 handbuilt units are distinguishable by the raised "pagoda style" scoop bonnet. Some of these Iso Grifo 7 Litri units were rebuilt later with even bigger engines. The idea of Bizzarrini was to use the 3AL cars for competition. The competition versions of the Grifo were named Iso Grifo A3C, C for Competizione or Corsa. A new lightweight riveted aluminium body was designed and built by Piero Drogo. It was an aggressively-designed machine, oriented to endurance races. It uses normal Iso underpinnings but the engine was moved further back in the chassis frame than the Grifo A3L, protruding well into the driver's cabin, fitted with hot cams and fed by four big Weber carburetors, giving more than . Around 29 A3C sport cars were built under the Iso name. Five of these 29 cars were bodied in plastic/fiberglass by Piero Drogo at Carrozzeria Sports Cars in Modena. A3Cs were