At the Geneva Motor Show in 1966, ASA has a more special version of the 1000 GT model: the RB (for "Roll-Bar"), with a "targa" type body, with a rear-mounted rollbar, a removable roof and fiberglass body, made in collaboration with the Carrozzeria Corbetta. The style is reminiscent of the Corvette Sting Ray and the shape is undeniably pretty. Under the hood there is a new engine: it is a six-cylinder 1290cc, the same configuration as the original four-cylinder Ferrari, overhead camshaft and fed by three Weber twin choke carburetors, developing 124bhp at 6000rpm. For the U.S. market, a four-cylinder 1800 was considered, but the model did not see the light of day.
For reasons of costs of production, this beautiful car will not be sold but just three examples are made. Two of them participated in the 24 Hours of Le Mans in 1966, one in the colours of the team of Luigi Chinetti, who was himself involved in the genesis of this model, and which will be driven by Pasquier/Mieusset. The other car is entered by the factory with Dini/Giunti at the wheel but neither of them reached the finish line, one due to a collision with a CD, the other due to transmission problems.