Guide: Alfa Romeo C52 'Disco Volante'
Background
With the Tipo 158 and 159, Alfa Romeo had won the inaugural 1950 and 1951 Formula 1 World Championships for Drivers. In the absence of a Constructors crown (not introduced until 1958), the Drivers’ contest was the most prestigious title in motor sport.
For 1952, the F1 regulations restricted entrants to normally-aspirated two-litre engines.
Alfa’s double championship winning machine was an updated pre World War 2 design with a 1.5-litre supercharged engine. It was at the end of its development life and the firm did not have the money to build a replacement so the Formula 1 programme was dropped.
Instead, Alfa Romeo planned a limited sports car campaign with a machine tenuously based on the forthcoming 1900 road car. The experimental C52 would be a collaboration between Alfa Romeo’s competition department, the firm’s chief designer, Gioacchino Colombo, and Carrozzeria Touring of Milan.
In November 1951, the 1900 C Sprint road car was unveiled. Factory-prepared examples were then raced at the 1952 Giro d’Sicilia and Mille Miglia, but they proved no match for larger displacement Grand Tourers from Ferrari, Lancia and Maserati.
Between the Giro and Mille Miglia, the C52 broke cover. It was unveiled at the New York International Motor Sports Show held from March 29th to April 6th. This unusual location was chosen as Alfa Romeo’s US importer, Max Hoffman, had encouraged the project and was keen to sell production versions to customers.
Bodywork
Understandably, most attention focused on the C52’s extraordinary appearance which Alfa Romeo and Touring of Milan had teamed up to produce. Extensive wind tunnel tests dictated its form and resulted in a drag coefficient of 0.25, the lowest of any vehicle at the time.
In addition to the front profile, considerable attention was paid to the sides, rear and the fully faired-in underbody. It was an extremely handsome thing; the rounded wings, pointed tail, large side overhangs and partially shrouded wheels led to it being nicknamed ‘Disco Volante’ (Italian for flying saucer).
Chassis
Under the light alloy bodywork was a state-of-the-art tubular spaceframe chassis with a 2220mm wheelbase.
Suspension was lifted from the 1900 C; double wishbones at the front with a live axle linked to the chassis by an upper triangle and two lower longitudinal reaction arms at the rear. Coil springs and telescopic shocks were fitted all round along with hydraulic ventilated drum brakes.
The 16-inch diameter Duralumin wire wheels were shod with Pirelli tyres and measured 6-inches wide.
Engine & Gearbox
Special engines were used that featured a host of upgrades over the standard 1900. Most notably, Alfa Romeo ditched the cast iron block for one formed in aluminium. The alloy head was press-fitted with 2000cc wet cylinder liners and bored from 82.55mm to 85mm. Stroke went unchanged at 88mm which resulted in overall displacement rising from 1884cc to 1997cc.
Compression was raised from 7.75 to 8.73:1 and a pair of enormous twin-choke Weber 50 DCO 3 carburettors were installed. These were of the sidedraught variety to allow for a flatter bonnet profile.
The inline four cylinder engines with their chain-driven overhead camshafts were mounted longitudinally in the chassis and produced 158bhp at 6500rpm.
Transmission was via a four-speed gearbox with synchronised forward gears, a limited-slip differential and twin-plate clutch.
Interior
As it was designed purely for competition, the C52’s cockpit was understandably bereft of any superfluous trim. Conditions were cramped with space restricted by the offset transmission tunnel.
Weight / Performance
Weight was a quoted 735kg and the C52 was reputedly capable of around 150mph.
Testing
Upon returning to Italy from the New York Show, Alfa Romeo conducted tests at a number of circuits. In late May, they announced their drivers for Le Mans which would be held over June 14th and 15th. Four of the new sports racing cars were expected to be on hand for Juan Manuel Fangio / Jose Froilan Gonzalez, Franco Cortese / Consalvo Sanesi, Emmanuel de Graffenreid / Willy Daetwyler and Giulio Cabianca / Bruno Ruffo.
However, no C52s ever made it to Le Mans. At the time, Alfa Romeo cited reliability concerns, but their absence was most likely due to the C52’s stability issues; in tests the bodywork was found to develop significant lift at both ends. Accordingly, none of the C52s ever raced in their original ‘Disco Volante’ configuration and the project was switched to an R&D programme.
Production / Developments
Four C52 Spiders were originally completed including one (1361.00011) with a prototype three-litre inline six-cylinder engine. This powerplant was a development of the unit used in the unique C50 that raced at the Mille Miglia in 1950. Displacement was increased from 2443cc to 2995cc, compression was upped to 8.0:1 and with three Weber carburettors, it produced an estimated 200bhp. Visually almost identical to the two-litre C52s, the longer cast-iron engine block required a small extension to the wheelbase. A second three-litre long wheelbase example was also partially completed on chassis 1361.00012 before being dismantled.
As part of the research and development programme, the three-litre long wheelbase car (1361.00011) was used as a test bed for the 1953 6C 3000 CM and soon fitted with an even bigger 3.5-litre motor. Although no official figures were ever quoted for this car, in 3.5-litre configuration, output was reputedly 240bhp and weight rose by circa 25kg to about 760kg.
Re-bodies
Around the same time, two of the three short wheelbase C52s with the smaller 1997cc engines were re-bodied by Touring. During the summer of 1952, one was given a straightforward conversion to become a Berlinetta ‘Disco Volante’. This car (chassis 1359.00003) was later displayed at the Turin Motor Show in April 1953.
The second example to receive modified coachwork (1359.00002) was reworked with a more conventional Spider body. This newly reconfigured Spider was nicknamed ‘Fianchi Stretti’ on account of its standard fenders that replaced the bulging semi-shrouded wings of the original ‘Disco Volante’. Further changes were made at the back where a cropped tail replaced the pointed rear end in an attempt to reduce lift and improve stability. Various other modifications included wider 6.5-inch wheels and Weber 40 DCOE carbs for easier running. The bodywork changes had a dramatic effect on performance and, so impressive was the transformation, Alfa Romeo reversed their earlier decision not to race the C52.
Competition History
The ‘Fianchi Stretti’ made its competitive debut at the Pescara 12 Hour race on August 16th 1952. Driven by Pietro Palmieri and Francesco Matrullo, the Alfa was pitched against two-litre contenders from Lancia (Aurelia) and Fiat (8V) but failed to finish.
It next appeared on the 1953 Mille Miglia as part of a four-car Alfa Romeo team that included a trio of new 6C 3000 CMs. Held over April 26th and 27th, the Mille Miglia was round two of the inaugural World Sportscar Championship and, for a while, it looked as though the 6C 3000 CM of Juan Manuel Fangio and Giulio Sala would win. However, they were forced to slow owing to a steering problem and eventually placed second. None of the other Alfas finished including the ‘Fianchi Stretti’ which was driven by Goffredo Zehender and navigated by A. de Giuseppe.
Luigi Bellucci was then entered to drive the C52 in a 30 lap race around the Avellino street circuit on July 12th. An event for under two-litre sports cars, Bellucci finished two seconds behind the works Maserati A6 GCS of winner Luigi Musso and was the only car not to be lapped.
Two weeks later, the ‘Fianchi Stretti’ was entered for another major endurance event: the 10 Hour night race around the streets of Messina. A unique event on the calendar with a start time of 10pm, the victorious Ferrari 250 Mille Miglia of Eugenio Castelotti and Giulio Musitelli covered over 1100km. Twelve laps behind the winners was the C52 driven by Vivaldo Angeli and Armando Soldani. They finished eleventh overall and third in class with Fiat 8Vs taking first and second in the under two-litre Sport category.
At the Giro delle Calabria on August 2nd, Luigi Bellucci was back in the C52 and finished the 723km road race third overall. Luigi Musso was once again the victor in his works Maserati A6 GCS followed by the Ferrari 166 Mille Miglia of Giulio Musitelli.
Bellucci was also present for the Merano Supercortemaggiore on September 6th. This 15 lap race attracted another fine field of cars and was won by Juan Manuel Fangio in Alfa’s new Spider version of the 6C 3000 CM. Bellucci was not classified among the finishers.
The ‘Fianchi Stretti’s final appearance of 1953 came in the Coppa Sant Ambroeus at Monza on November 1st. A ten lap race for sub two-litre sports cars, Piero Carini drove the Alfa and finished second. The race was won by Giuliano Ronzoni’s exceedingly rapid Zagato-bodied Fiat 750 special.
At the end of 1953, Alfa Romeo closed their competition department to concentrate on supporting privateers. The other surviving C52s (chassis 1359.00001 the original Spider ‘Disco Volante’ and 1359.00003 the converted ‘Disco Volante’ Berlinetta) were retained by Alfa Romeo. The six cylinder ‘Disco Volante’ Spider (1361.00011) was donated to the Biscaretti museum in Turin (now the Museo Nazionale dell’Automobile).
In October 1954, 1359.0002 (the ‘Fianchi Stretti’) was sold to amateur Swiss driver, Jean Ducrey. Prior to hand-over, it was given a gentle shakedown at the Coppa d’oro di Siracusa (October 10th) where Nicola Musmeci drove steadily to eighth in the over 1.1-litre sport class.
Two weeks later, Ducrey entered it for the Penya-Rhin GP at Pedrables in Barcelona (October 23rd) but was not listed among the top finishers. Between 1955 and 1959, Jean Ducrey continued the ‘Fianchi Stretti’s occasional competition career, participating in a mix of circuit races and hillclimbs.
By April 1963 it had found is way to Fritz Schlumpf and became part of the world famous Schlumpf Collection in Mulhouse (now the Cite de l’Automobile).
Text copyright: Supercar Nostalgia
Photo copyright: Alfa Romeo - https://www.alfaromeo.com
