With a sleek body designed by Franco Scaglione and mechanicals by ex-Ferrari virtuosos Carlo Chiti and Giotto Bizzarrini, the ATS set the motoring world reeling with the first mid-engine Italian sport and GT car. Chiti and Bizarrini were part of the 'palace revolt' at Ferrari, which resulted in Enzo's firing six key employees in 1961 over complaints of his wife's meddling. The six ex-Ferrari men immediately set out to seek financing to start their own Formula One and GT car venture. The GT car, which debuted at the 1963 Geneva Show, was a great success in that it was highly praised for its very rigid and advanced space frame chassis, its handling, and high-speed performance. Unfortunately, however, the investors withdrew financial support, and the project collapsed. Only a few cars were completed by the factory.

The mid-mounted 2.5-liter 90-degree V8 engineered by Chiti developed 245 horsepower and endowed the ATS with a top speed of approximately 160 mph. The aluminum overhead camshaft engine was paired with a five-speed competition transaxle. The chassis was a sophisticated tube-frame design with four-wheel independent suspension, disc brakes, and rack-and-pinion steering.