From 1933 to 1938, the Grand Prix was run to the Formula Libre standard, meaning that no weight or engine restrictions were enforced on what was then the fastest track in the world. In 1939 the Italians, tired of Germany’s dominance, turned it into a Voiturette race for smaller, 1500cc cars, but even so, a specially-built Mercedes driven by Hermann Lang won. In 1940, with only the factory Alfa Romeo and Maserati teams plus some independents in attendance, Giuseppe Farina took his only major pre-war victory. It was a last and pyrrhic result for the Italians because the Tripoli Grand Prix was never held again with the onset of World War II.
In 1939 the, Grand Prix was limited to 1.5 litre cars. The task of redesigning a new race care for the coming race season was daunting.Yet, Mercedes-Benz succeeded in building an entirely new racing car at a record pace. The 1.5 litre W 165 with a V8-engine pushed out a remarkable 256hp. With the Mercedes-Benz W 165 race car, Hermann Lang gained international fame as a result of an outstanding team performance and one of the most unexpected triumphs in the history of motor sport. Therefore it is not surprising that this car and the Tripolis race became a legend.