O.S.C.A. is the acronym of Specialized Car Construction Workshops.

In 1937 the brothers Ettore, Ernesto and Bindo Maserati had sold their factory (the Officine Alfieri Maserati) to Adolfo and Omar Orsi, owners of a steel and tool factory. The transfer agreement provided for ten-year consultancy for the Maserati brothers, after which they decided to found their own workshop in 1947 for the production of small-engine racing cars called OSCA. The first model produced by the San Lazzaro company was the barchetta MT4 from 1948, powered by a 1092 cm³ twin cam engine with 72 HP and intended for competitions in the 1.1 liter category.
The MT4 won the 1948 Naples Grand Prix, driven by Luigi Villoresi and won several victories in the engine capacity class, driven by Ada Pace, including a prestigious victory in the Targa Florio.

In the following years, evolutions of the twin cam followed with displacements of 1392 cm³ of 92 HP, 1453 cm³ of 110 HP, 1491 cm³ of 120 HP and 1568 cm³ of 140 HP. Osca MT4 2AD on the right and an Osca S187 on the left
The "1600 GT" and "1600 GT2" chassis derived from the racing cars, transformed into elegant 2-seater coupés and spiders by the coachbuilders Frua, Michelotti, Zagato, Fissore and Vignale.
The ambition to participate in the sports world championship and in the Mille Miglia led to the birth of the MT4 equipped with a 2-litre engine, DOHC with desmodromic timing, delivering 165 HP.
This car, driven by Stirling Moss, added victory in the prestigious 12 Hours of Sebring to the OSCA palmarès.
The Osca twin-cam engines, first 1491 cm³ and then 1568 cm³, went on to equip, in a depowered version at 90 HP SAE (80 HP din) and 100 HP SAE (90 HP DIN), more widespread models, such as the Fiat 1500 S (1959-1963) and 1600 S (1963-1966). The Maserati brothers, now elderly, sold the majority shareholding to the Agusta counts, already owners of the motorcycle and helicopter companies of the same name, at the end of 1964.
At the end of 1966 most of the staff in Bologna was fired and it was decided to transfer the company to Gallarate, but already in 1967 OSCA closed its doors.