This model proved successful and was one of the first to do well outside Italy, helping to build a reputation for Ferrari in the all-important American market. The 166 Inter models were the road versions of the 166 sports racing models like the 166 MM barchettas, hence they carried chassis numbers in the odd series range, and were produced between 1948 and 1950. They normally had coupé bodywork, although Stabilimenti Farina produced three examples in cabriolet form and Bertone also produced a single cabriolet body for the model. Various coachbuilders’ bodywork was fitted to the series, all with their own interpretation of how they felt a Ferrari should be coutured.

Apart from Stabilimenti Farina, Bertone, and Carrozzeria Touring, the latter having bodied the first 166 Sport coupé for the 1948 Turin Salon, there were also examples of coachwork from the design houses of Ghia and Finale.

The Carrozzeria Touring examples were the most numerous, and bore a strong family resemblance to the style of their 166 MM barchettas, albeit on a longer wheelbase chassis, and with a smoothly curved three box coupé body. The examples from Stabilimenti Farina and Ghia were very similar in overall shape, featuring fastback coupé bodies that appear slightly heavier in comparison to the Touring interpretation, whilst the Stabilimenti Farina cabriolets were virtually identical to the coupés from the waist down, and featured a folding canvas soft top, as did the Bertone bodied car.

The Finale styling offering was also a fastback coupé, but of a much lighter design than those from Farina and Ghia, providing a stronger sporting image, which made them second in popularity, in terms of numbers produced, to the Touring version.

Although any two models from one coachbuilder might appear identical, each body was hand-built, and the client had the opportunity to indulge in his or her personal styling whim, so that virtually every car was an individual, and there would often be numerous detail differences, perhaps in the radiator grille design or lighting layout, between one car and another from the same source.

Although the Inter series were built as road cars, many owners used them frequently in competition, and they acquitted themselves well, despite the heavier bodies and full interior trim, relative to their sports racing peers.

As the Inter series were road cars, front and rear bumpers were part of their apparel, the Touring-bodied cars having vestigial appendages normally faced with rubber strips, whilst those on the Ghia, Farina, and Finale-bodied examples were much heavier chrome-plated adornments.

The mechanical layout on a 2420 mm wheelbase tubular steel chassis was very similar to the 166 competition models, with a 2-litre V12 aluminium engine coupled with a 5-speed gearbox driving through a rigid rear axle. The engines on these models had a twin distributor and coil ignition system, and were fitted with a single twin choke carburettor as standard although a triple twin choke carburettor set-up could be specified as an option to obtain extra performance.

These were the only road production Ferrari models of the period available with disc type road wheels, as an alternative to the more popular and sporting wire wheels. In either instance they had Ridge type splined hubs, sometimes under a chrome hub cap on the disc wheels.