Mario Alborghetti was a wealthy gentleman racer from Milan. He is remarkable in that he basically entered a Formula One race with no previous experience. He had only competed in four minor events before commissioning his own racecar and entering the Pau Grand Prix in 1955.
His commissioned Gianpaolo Volpini and Egidio Arzani to build a car for him along "Squalo" lines. This was called the Arzani-Volpini. It was built in Milan using parts from the Scuderia Milan cars from the old Formula 1. It had a twin-cam four-cylinder engine with eight plugs, and four single choke Webers, a four-speed gearbox on the back axle, double wishbone suspension with torsion bars, and trailing link rear suspension with a transverse leaf spring.
He was due to race in the VII Gran Premio del Valentino on the 27 March 1955 at Valentino Park, Italy, but his Scuderia Volpini Maserati 4CLT/48 was not ready.
Two weeks later, in April, he arrived in Pau for the Grand Prix. Alborghetti was very slow in practice, with times similar to Storez and Armagnac and their DB's supercharged monomilles, some ten seconds slower than the next fastest qualifier.
In the race he was no quicker and he had already made three pit stops by lap 19 when he crashed heavily into the straw bales at the tight Station corner. It is a mystery as to what actually happened. Though reports say that Alborghetti was braking for the tight Station hairpin when Pollet went by on the inside to lap him.
The suggestion that Pollet was involved is quite likely as he would have been overtaking Mario on the inside at that point. What happened next is unclear but it appeared that Alborghetti accelerated suddenly and crashed straight into the straw bales. Alborghetti's helmet came off. He was killed and nine spectators were injured.