1955 Maserati 150S

During the 1950s, racing categories were simply defined by engine displacement, and Maserati's portfolio of race cars was very accommodating. The A6G series was a formidable competitor but as it aged, a four-cylinder replacement was needed. Maserati's approach was to build the 150S and the 200S simultaneously, with slightly different bodywork and the former equipped with a 1.5-liter and the latter with a 2.0-liter engine. Mechanical components were similar, with a de Dion rear suspension replacing the prior live axles.

Maserati's six-cylinder competitor was the Maserati 300, built between 1954 and 1958, with its 3.0-liter engine delivering 280 horsepower. The 300S and its 3-liter engine were closely related to Gioacchino Colombo's Maserati 250F Formula One monoposto. The lightweight chassis was developed from the previous Maserati A6GCS, and the body was built by Fantuzzi.

The Maserati 350S used a modified 300S chassis and a bored-out 300S engine, and only three examples were built.

Nine examples of the Maserati 450S were built from 1956 to 1958 and raced in endurance World Sportscar Championship racing. They were probably the fastest Maserati sports car ever made and intended to challenge the V12-equipped Ferrari sports-racing cars. Power was sourced from a front-mounted 4.5-liter V8 engine installed in a lightly modified 300S chassis. The engine was too powerful for the chassis, so a new tubular chassis was built.

The Maserati 150S
Approximately twenty-four to twenty-seven examples of the Maserati 150S were built from 1955 to 1957. Known as the Tipo 53 it was designed by Vittorio Bellentani and Medardo Fantuzzi in 1953 with a front engine, rear-wheel drive configuration with no doors and two seats. The wheelbase initially measured 84.6 inches, later growing to 88.6 inches (the first four or five cars had the 84.6-inch wheelbase; beginning with chassis 1656, the wheelbase was 84.6 inches), with an overall length of 170 inches, a width of 71 inches, and an overall height of 45-inches. The tubular frame chassis was similar to that of the A6GCS, but the previous live rear end was replaced by a de Dion setup with transverse leaf springs.

Maserati introduced its Type 150S in April 1955 at the Turin Motor Show, and the final example was completed in January 1957.

Maserati 150S Engine
Development of the engine began with Alberto Massimino's earlier two-liter unit, an early champion of Maserati's four-cylinder program. He left for Stanguellini in late 1952 and was replaced at Maserati by Gioacchino Colombo. Giulio Alfieri, who joined Maserati in September 1953, preferred the six-cylinder design, and ultimately, the development of the 150S and 200S never fully reached its potential.

The 1,484cc dual overhead camshaft inline four-cylinder engine had twin Weber 45 DCO3 carburetors and produced 140 horsepower at 7,500 RPM. It was initially paired with a four-speed transmission with Porsche patent synchromesh but later replaced by a five-speed manual gearbox with a ZF limited-slip differential. Hydraulic drum brakes were located behind each wheel. The suspension was by independent double wishbones at the front, and the rear used a DeDion tube with transverse leaf springs.

Maserati 200SI Engine
The 1,993cc DOHC twin-plug four-cylinder engine powering the 200SI produced 195 horsepower at 7,500 RPM when equipped with twin Weber 45 DCO3 carburetors. It was paired with a five-speed manual ZF gearbox, and stopping power was via four-wheel hydraulic drum brakes. The suspension was independent at the front with wishbones, shock absorbers, and coil springs. The rear used a DeDion axle with transverse semi-elliptic leaf springs and shock absorbers.

Body Design
Modern, attractive, angular, and curvaceous bodywork was bestowed upon the 150 S and other Maserati sports racing cars. At the front was an aggressive, sloping nose complemented by a truncated rear end and a faired underbody.

Sportscar Racing
In the very competitive 1.1 to 1.5-liter sports racing category, the Maserati 150S performed admirably, with most examples sold to privateers. Among the accolades was a victory by Jean Behra at the half-sized 1000km Nürburgring in 1955, and Alejandro de Tomaso finished fourth overall at the 1956 1000 km Buenos Aires.

by Daniel Vaughan | Sep 2023