The new 6 cylinder OM 665 (six cylinders, 65 bore x 100 mm stroke) was the queen of the Motor Show at the Milan Trade Fair of 1923. The house designer Ottavio Fuscaldo had retained the overall 4-cylinder architecture of the previous model’s engine and chassis by using the apparently simple solution of adding two cylinders to the engine block and redesigning the drive shaft. The result was a car that, every time it is pulled back from oblivion, is considered one of the best Italian cars of its time. Unquestionably the blueprints emerging from the Brescia Technical Office had produced a miracle of lightness and simplicity. The model displayed in Milan in 1923 had other exclusive aspects compared to the 4-cylinder: the Bosch 12 V electrical and lighting system, for example.
The factory proposed a wide variety of bodies. The 1927 model list includes various types of phaeton, including the Mylord, the Bateau and the Weymann, the Limousine coupé Deluxe, the Landaulet coupé, the Saloon and, finally, the most expensive of them all, the Cabrio Saloon convertible phaeton.
After Milan, the vehicle was also shown in Paris and Geneva and was widely acclaimed in the press. Road-holding that was exceptional for the time, smooth gear changing, efficient brakes and sharp acceleration and overall manoeuvrability were the qualities generally highlighted in the press coverage which also underlined the fact that the car had the speed and acceleration to satisfy even the most sporty customer. At the Milan Show of 1931, OM showed a saloon on an N5 chassis, “…..which embraces all the features of the great marque even though it fits a small capacity engine. A staid car with a sturdy, elegant, safe line…In this type of car, any dangerously refined mechanical excesses are rejected. The model stands firm as a clean-lined, absolutely safe mechanical construction”.
In 1931 the chassis of the N5 cost 34,000 lire, the complete car 49,000 lire.
