Alfa Romeo followed its Grand Prix Championship triumph of 1950 with a repeat performance in 1951 when the Argentinean driver Juan Manuel Fangio won the title after battling with Alberto Ascari in a Ferrari. The winning GP159 single seater was based on the previous year’s 158, designed by Orazio Satta, but with modifications including De Dion type rear suspension, a lighter, reinforced tubular frame, increased braking power, modifications to the body and a new gearbox.
Power output was increased to 425 bhp. Nicknamed the Alfetta (Little Alfa) because of its size, it was the most powerful 1500 ever made. Immediately thereafter, Alfa decided to withdraw from Grand Prix racing. It continued to compete in other races, however, and produced the lens-shaped 1900 Disco Volante with a top speed of 225 km/h for this purpose.