MT4 or Osca MT4, is an Italian sports car prototype, designed, developed, and made by Officine Specializzata Costruzioni Automobili, between 1948 and 1956, but was raced and used in active competition until 1966.

[1][2][3][4] Due to the variety of engines of different displacement sizes and the comparatively large number of chassis built (thanks to strong sales), the OSCA MT4 had an unusually long service life for a competition car.

In 1947 they were finally free to go their own way; Officine Specializzata Costruzioni Automobili Fratelli Maserati was founded and the first vehicle type, the MT4, was built.

[9] OSCA soon developed a new 1,092 cc engine, which produced 72 PS (53 kW; 71 hp) at 6,000 rpm, had a in-house designed aluminium block and alloy head.

The bodywork on early models was a two-seater roadster with or without cycle fenders, lights, and the various other accoutrements required to make it street legal.

[16] The listed price was $10,000, enough to buy three V8-engined Ford Thunderbirds with a good margin, but on the other Road & Track stated that the OSCA had outperformed every lower-priced car ever tested by them.

The reviewers also remarked on the rarity of an Italian-made car matching the manufacturer's claimed top speed, acceleration, and weight figures.

The first such engine was installed in the Simpson Special; a record-breaking streamliner on an MT4 chassis which beat numerous land speed records at the Bonneville Salt Flats in 1955.

The OSCA MT4 is best known for the 1954 12 Hours of Sebring, where it won outright against much more powerful cars with drivers Stirling Moss and Bill Lloyd[18] as part of the Briggs Cunningham Team.

In the April 6, 1992 issue of AutoWeek, Cunningham stated that, of all the automobiles he built, owned, and raced, the OSCA was his favorite racecar.

[21] The new engine produces 135 hp (99 kW) in sports racing (FS) trim; the new design meant that unlike on earlier OSCAs, the exhaust exited on the right hand side of the car.

[23][24] The Giro delle Calabria was won by Dorino Serafini and Alberico Cacciari ahead of Luigi Fagioli, who also drove an MT4.

At the 12 Hours of Sebring, Stirling Moss and Bill Lloyd won the general classification for Briggs Cunningham's team.

This was evident, for example, at the 1956 Mille Miglia, where Cabianca and Umberto Maglioli fought for the lead in the early stages of the race with the Ferrari and Maserati works drivers.