At the second edition of the Monza 500 Miles, in 1958, Maserati entered a single-seater built with the financing of Gino Zanetti, owner of the Eldorado ice cream company. The car, called 420 M-58, had a tubular frame similar to that of the 250 F but lightened and the V8 engine derived from that of the 450 S, with a displacement reduced from 4.5 to 4.2 liters and a power of approximately 410hp . The engine was mounted on the left side of the chassis, to aid the car's stability on a counter-clockwise turning track. The gearbox had two ratios, the first of which was used only for starting off. With Stirling Moss at the wheel, the 420 M-58 provided an excellent performance but Moss had to retire due to steering failure in the third heat. Moss was still classified seventh. The car was then revamped and renamed 420 M-59 and took part, without qualifying, in the 1959 Indianapolis 500 with Ralph Liguori.