Eugenio Castellotti, early in the 1955 Le Mans race, at speed through Dunlop Curve in one of the three Ferrari 121LMs, as the Ferrari in-line six was then called when fitted with the latest and most powerful 4.4-liter motor. This was during the “Grand Prix” in the initial hours between Castellotti, the Jaguar D-Type driven by Mike Hawthorn which was the eventual winner, and the Mercedes 300SLR of Juan Manuel Fangio.
In 1955 Ferrari had tried a new sports car engine, a six cylinder in-line unit derived from their highly successful four cylinder motors. Like the fours, the sixes were designed by the famous Aurelio Lampredi whose four cylinder designs helped Ferrari win two Grand Prix World Championships in 1952-53. The reason for this new motor was to try to have more power in the face of the expected arrival of Mercedes-Benz in the 1955 sports car races, after the German firm had displayed its Grand Prix potential in 1954. This step was in keeping with Ferrari’s philosophy of the time that a car’s engine was by far the most important factor in racing success.
Ferrari began this experiment in mid-1954 with a three-liter six which was used only in testing. The next stage was a 3.7-liter six which was installed in a new chassis for the Buenos Aires 1000km race which took place in January 1955. This first car, produced in October 1954, had the same short wheelbase as the new four cylinder sports car which would become the highly successful 750 Monza. The new six was generally referred to at Ferrari as a 735-6c, 735 referencing the capacity of a single cylinder of its 3-liter four-cylinder progenitor. The first outing of the new six was partially successful as it was the fastest car in the 1000km race, but was disqualified when driver Froilán González, thinking he was running out of fuel, took a short cut to the pits and was disqualified. Another outing a week later in Buenos Aires for a Formula Libre race, where Mercedes appeared with 3-liter Grand Prix cars, was even less positive when the six, driven by Umberto Maglioli, was quite uncompetitive versus faster company.
As one result, it was decided to lengthen the wheelbase of this first six cylinder to the Ferrari normative 2400mm for better stability, as set out in the latest chassis drawing for the model, although actual measurements indicate that at least three of the four six cylinder cars built were subsequently lengthened to only about 2350mm. After a few European races, worries about the new six became stronger. Although Eugenio Castellotti had led the Mille Miglia for a short time at a fantastic pace with a new 735-6c before the engine expired, only one of the four Ferrari six cylinder entries made it to the end, the win going to Stirling Moss with a Mercedes. Time and again there had been overheating and engine failures with water leaking into the lubrication system, probably caused by the engines’ undamped harmonic vibrations. Development to address these problems never happened, perhaps because Lampredi’s political star already was declining after an abortive 2-cylinder experiment which the failures of the sixes did nothing to overcome.
For Le Mans, Ferrari entered three of the sixes with the original Buenos Aires car left at Maranello to be sold to American Tony Parravano. All the Ferraris had the latest 4.4-liter motors but retired with engine problems. These 121LMs were indeed lovely cars, but too fragile to be successful. At the end of the season the three remaining sixes were also sold to American buyers. The lives of the four 121LMs in the States were marked by continued engine problems, although some of these cars would appear from time to time up to 1960.
Unfortunately, Le Mans 1955 became famous for a tragic reason: the crash of a Mercedes into the crowd across from the pits which killed over 80 and injured scores more.
Photo by Louis Klemantaski ©The Klemantaski Collection