The Maserati 4CL and its derived sister model the Maserati 4CLT are single-seat open-wheel Grand Prix racing cars that were designed and built by Maserati. The 4CL was introduced at the beginning of the 1939 season, as a rival to the Alfa Romeo 158 and various ERA models in the voiturette class of international Grand Prix motor racing. Although racing ceased during World War II, the 4CL was one of the front running models at the resumption of racing in the late 1940s. Experiments with two-stage supercharging and tubular chassis construction eventually led to the introduction of the revised 4CLT model in 1948. The 4CLT was steadily upgraded and updated over the following two years, resulting in the ultimate 4CLT/50 model, introduced for the inaugural year of the Formula One World Championship in 1950. In the immediate post-war period, and the first two years of the Formula One category, the 4CLT was the car of choice for many privateer entrants, leading to numerous examples being involved in most races during this period.
The 4CL
Design
In the late 1930s, continued rapid development in the increasingly competitive international voiturette class, and the introduction of the Alfa Romeo 158 and ERA B- and C-type models, forced the Maserati brothers into designing a new, square-bore,inline-4-cylinder engine, with a bore and stroke of 78 mm for a total displacement of . This new engine developed 30–50 bhp more than the previous inline-6, the increase mostly achieved through an increase to four valves per cylinder, coupled to the use of a more powerful supercharger and a small increase in the compression ratio. Following customary Maserati practice, the engine was mounted into a chassis design almost identical to that of the 4CL's predecessor: the Maserati 6CM. Conventional in its architecture, twin box-section spars ran the length of the car joined, ladder-fashion, by smaller cross members, although the 4CL design did incorporate more aluminium componentry than its forebear. Although near-identical in its wheelbase, the 4CL's track was a full wider than the 6CM, and sat lower thanks to repositioned spring hangers.
Enveloping this rather conservative chassis was a low, curvaceous alloy-panel body, built in-house by Maserati. Maserati also built a streamlined version of the 4CL from the outset. Continued engine development, in response to Alfa Romeo's post-war introduction of two-stage supercharging, began to expose weaknesses in the chassis design. In an attempt to improve torsional rigidity Maserati began to experiment with tubular section chassis members. These experimental models ran alongside conventional 4CLs throughout the 1947 season, and eventually led to the introduction of the 4CLT in 1948.
Race history
In the hands of Luigi Villoresi the streamliner took pole position on the 4CL's race debut at the 1939 Tripoli Grand Prix, ahead of Mercedes' brand new W165s. However, both it and two of the three conventional 4CLs entered retired early in the race with engine troubles, leaving the Silver Arrows to take the victory. Embarrassingly for the works team, following this disappointing debut the 4CL's first taste of victory came in the hands of privateer Johnnie Wakefield at the Naples Grand Prix, two races later. Through the remainder of 1939 voiturette races Wakefield took two further victories, and the works' 4CLs picked up another two, before the outbreak of war curtailed international competition. Villoresi took the 4CL to victory in the 1940 Targa Florio, but with entry restricted to Axis countries, and only Maserati fielding a factory team, the opposition was hardly world class.
On the resumption of competition in 1946 the Maserati 4CL proved the class of the field. Luigi Villoresi immediately returned to winning ways, taking victory in the first race following the cessation of hostilities: the 1946 Nice Grand Prix. Tazio Nuvolari and Giorgio Pelassa both took wins in 4CLs, but it was Raymond Sommer and his 4CL who dominated the season. 1947 would prove to be the 4CL's most successful season and, despite Alfa Romeo fielding the revamped 158 and new 308, Maserati drivers picked up 10 individual race victories.
After the replacement of the factory team's 4CLs by the new 4CLT, many examples of the older cars found their way into privateer hands. It was owing to the 4CL's popularity with privateer entrants that many were still being run in top-flight competition at the outset of the Formula One World Championship in 1950.