About us

Testadoro is an italian small car manufacturer, funded in Torino in 1946, known for its high-performance sports and racing cars. With a legacy that spans decades, we continue to innovate and deliver top-quality vehicles to our customers. Visit our website to learn more about our history and current models.

History

Testadoro: A Legacy of Excellence in Post-War Motorsport

Testadoro has been a key player in the revival of sports car racing in the post-war era. In a country devastated and lacking resources, the passion for engines and racing surged with incredible intensity, leading to races with any available means. In the spirit of racing at any cost and with any vehicle, the first post-war Mille Miglia saw the participation of mostly old Fiat 500 "Topolino" and 1100 "Balilla" cars. However, these vehicles had outdated and weak engines, prompting several tuners to market kits for the sporty preparation of standard engines as early as 1946.

It was in this context that Milanese engineer Arnaldo Roselli, who had been part of the Ferrari team in 1935, designed a cylinder head for the modest 995cc engine of the Topolino. The head could be mounted in a few hours on the original base and featured radially positioned overhead valves, a solution reserved at the time for competition prototypes. The head was originally cast in bronze, giving it the characteristic golden color that led to its commercial name "Testadoro."

Testadoro was an active brand in the 1940s, producing racing cars, engines, and parts for the sporty tuning of standard engines.

The Testadoro Brand: A Symbol of Innovation and Performance

The Testadoro brand was given to a special cylinder head for engines (originally for the Fiat 508 "Balilla") designed by engineer Arnaldo Roselli in the late 1930s. The term "Testadoro" was coined due to the distinctive color of the head itself, originally cast in bronze. Following a meeting with Turin entrepreneur Giorgio Giusti, the head was also produced for the more popular Fiat 500, known as "Topolino," which allowed for greater product distribution and provided owners of the widespread Turin utility vehicle with increased power and, according to contemporary advertisements, reduced fuel consumption. It should be noted that the standard "Topolino" was credited at the time with only 13 HP, making it slow and cumbersome despite its very light construction. The "Testadoro" was available in three different versions, varying in compression ratio, power, and use: "N-Normale," "S-Sport," and "C-Corsa."

Giorgio Giusti 

A Turin entrepreneur, Giusti was, along with Giorgio Ambrosini, one of the driving forces behind the Scuderia Subalpina founded by Count Luigi della Chiesa in 1935. The team then served as the official Maserati team. Following his meeting with Roselli, who was then with Scuderia Ferrari, Giusti proposed the production and mass marketing of the Testadoro for the Fiat 500 through his company, Casa dell'Auto in Turin. After three intense years of racing and victories, including competing personally as a driver of his cars, Giusti retired from racing in 1949 following the death of his partner Roselli in the autumn of that same year.

Arnaldo Roselli 

An engineer who had been with Scuderia Ferrari, Roselli was one of the designers (along with Luigi Bezzi and Enrico Bertacchini) of the infamous Alfa Romeo 16C Bimotore in 1935, commissioned by Enzo Ferrari to counter the dominance of German cars in the Grand Prix of the time. Roselli independently designed a head with hemispherical combustion chambers and radial valves for converting standard Fiat 1100 A engines into racing engines for the Sport 1100 class. Following his partnership with Giorgio Giusti, he designed the 750cc head for converting the standard Fiat 500 engines. He died in the autumn of 1949 in a car accident along with Dante Spreafico, a driver with several Mille Miglia races to his credit.

Evolution of the "Testadoro" intended as spare part and crate engine

1947 

The first version of the Testadoro for the Fiat 500 was cast in bronze and increased the displacement of the original base to 660cc. The use of the bronze alloy was intended, according to the designer, to provide greater rigidity and better thermal conductivity, characteristics that were supposed to ensure greater reliability over time due to less deformation at high temperatures. The combustion chambers were perfectly hemispherical, with the spark plugs arranged in a 90° V and the spark plugs in the center. This solution, characteristic until then of racing cars, allowed for larger valves and better combustion of the air/fuel mixture. The valves were always operated by the camshaft located in the original Fiat base, via rods, rockers, and special linkages. The compression ratio was 6.2 for the "Normale" version and 7.2 for the "Sport" version. The valve diameters varied depending on the version. This version of the Testadoro engine, still with the original Fiat base, was used on the first complete Testadoro cars, the "Sport" and the "Drin Drin."

1948 

In 1948, the "Testadoro" lost its characteristic color, as the casting changed from the original bronze to aluminum. The head remained immediately recognizable by the classic color of the valve cover, which featured the inscriptions "Testadoro" and "Casa dell'Auto – Torino" in relief. 1948 also saw the creation of an entirely in-house engine, abandoning the Fiat base for a new cast iron casting with three main bearings, which shared only the cylinder spacing of 61mm with the original (to maintain compatibility with the head). The engine was completed with a new chrome-nickel steel crankshaft with a stroke of 78, which, combined with a bore of 55, brought the total displacement of the 4-cylinder to 742cc, coming very close to the maximum displacement limit for competing in the 750 sport class. With a compression ratio of 9:1, this new complete engine developed a power of 45 HP at 6,500 rpm.

1949 

For the 1949 racing season, the Testadoro engine developed in 1948 was updated with steel cylinder liners subjected to nitriding treatment. This engine, the pinnacle of Testadoro development, delivered 48 HP at over 7,000 rpm and was paired with a 5-speed gearbox.

Testadoro 1100 

Although produced in smaller numbers compared to the more popular head for the Fiat 500, the Testadoro 1100 was used in some prestigious cars built around 1950: the Fiat 1100 Rovelli bodied by Castagna (with an innovative removable hard-top) and the Revelli-Monaco Testadoro 1100, designed by the famous designer Mario Revelli di Beaumont. A Testadoro 1100 barchetta was planned for the 1950 season (when changes in the "Sport" class regulations banned open-wheel cars), but it never saw the light of day due to Giusti's cessation of activities in the field of car racing.

Complete Testadoro Racing Cars

The Sport was the first car produced under the Testadoro brand in 1947. It featured an original Fiat engine, naturally equipped with the head that was the specialty of Casa dell'Auto in the 660cc version. The chassis was also the original "Topolino" one, although updated and "lowered," according to advertisements of the time. Equipped with a distinctive "barchetta" body adorned with numerous air intakes both at the front and on the sides, the "Sport" participated in various races, including the 1947 Circuito di Varese.

Testadoro Drin Drin 

Also in 1947, Giusti created a second "barchetta" with the same technical base as the "Sport." According to Andrea Curami, the car's distinctive name seems to be derived from the nickname of Giusti's wife, Andreina. This time, the car's design was entrusted to the expert hands of Zagato, who designed a vehicle characterized by extremely clean lines. The Drin Drin won a race at Montlhéry (France) and achieved numerous good placements, according to period chronicles.

Testadoro Marinella 

Evidently dissatisfied with the Topolino chassis still used in previous cars, for the 1948 car, Giusti turned to Gilberto Colombo, who was revolutionizing the world of racing car chassis. Colombo had designed and built the chassis of the first Ferrari in history, the 125 S of 1947, and had become Enzo Ferrari's exclusive supplier. Meanwhile, Colombo produced tubular steel chassis under the Gilco brand, ready for installation on the most popular mechanics of the time, such as the Fiat 500 and 1100. The tubular chassis were credited (according to Gilco advertisements of the time) with torsional rigidity 10 times greater than that of the classic mild steel ladder frames used by major manufacturers. With the ambition to create a complete car superior to the competition both in terms of engine and drivability, Giusti asked Colombo to create an exclusive chassis for Testadoro, completely different from the classic chassis produced for the 750 class (named G.C. 750 Sport and N.D. 750 S.). The Marinella chassis (named in honor of Giusti's first daughter) was of the "Isorigid" type, a trademark registered by Colombo, consisting of a lattice of small tubes appropriately triangulated for greater rigidity, directly derived from Colombo's experience in building Grand Prix chassis. The Marinella also had a suspension department worthy of higher-class cars, with a front double wishbone and coil springs, while many competitors had the classic transverse leaf spring. The Marinella was bodied as a "Siluro" by Zagato, with the "open" wheels characteristic of those years, with a streamlined shape following the chassis design. The car was obviously equipped with the new complete Testadoro engine of 742 cc and 45 horsepower and was produced in 9 examples according to many sources, making it one of the most widespread "ready-to-race" models of the time. With this car, Giusti himself achieved excellent results in numerous races, managing to outperform cars with much larger displacement but a more outdated overall design. The best result of the season was Giusti's victory at the "Coppa Michelin" held on the historic Valentino circuit in Turin.

Testadoro Marinella Hard-Top 

The "siluro" bodied cars were fast and agile, perfect for closed or city circuits. For endurance races, however, drivers increasingly preferred to have protection from the elements. Probably to meet these needs, a single example of the Marinella was prepared in a "barchetta" version with an original removable "hard top" to be used in longer races, such as the Mille Miglia and the Targa Florio. The car was officially presented at the Zagato stand at the first "Mostra della Carrozzeria Italiana" in Milan in November 1947. A fine photograph of this stand is present in the archive of the Turin Automobile Museum. On this car, even the young Elio Zagato attempted a racing career at the 1949 Targa Florio, paired with the "official" driver of the "Squadra Testadoro," Ugo Puma. According to Andrea Curami's book, this crew won the "sport up to 750cc" class of the prestigious Sicilian race, which was also valid as the "Giro di Sicilia" that year, with race number 122. The same car was entered in the Mille Miglia of the same year with the crew Ugo Puma – Aquilino Branca, with race number 234.

Testadoro Daniela 

The Daniela (named after Giusti's second daughter) is considered the pinnacle of Testadoro's development as a racing car manufacturer. Presented in 1949, it featured the improvements made for that season to the engine (742cc and 48 horsepower at 7,000 rpm), a new Isorigid chassis produced by Gilco, and a body (still a "two-seater siluro") again designed by Zagato. The Giusti/Colombo/Zagato trio produced a highly competitive car appreciated by both the press and the "gentlemen drivers" of the time. To testify to the importance of the car, as confirmed by some photographs preserved in the archive of the Turin Automobile Museum, Dante Giacosa, Elio Zagato, Nino Farina, and Carlo Biscaretti di Ruffia were present at its presentation. The project's quality was demonstrated by the numerous victories collected in 1949, including the Gran Criterium 750 of Monza on June 26 (absolute victory for Daniela No. 8 by Mejnardi). Among the other drivers of the "Squadra Testadoro" participating (Ugo Puma, Antonio Stagnoli, Aquilino Branca), the name of Nuccio Bertone stands out with number 14. Another important victory for Daniela in 1949 was at the Senigallia circuit, achieved by Ugo Puma.

Retirement from Racing and Derived Cars 

Following Giusti's decision to retire from racing due to Roselli's aforementioned fatal accident, the official support from the company to customers ceased. Given the overall quality of the project and the rarity of engine spare parts, many cars continued their sporting activity with a new engine. Andrea Curami, in his book "La Sport e i suoi Artigiani," particularly mentions the Marinella and Daniela built by Giusti's good friend and driver Aquilino Branca with a Moretti twin-cam engine, and the GI-CO Giannini G1 built by Armando Pasqualin based on Daniela.

Special Testadoro Cars 

Several original creations based on Testadoro are known, including the Zagato Fiat 500 Testadoro presented at the 1947 Turin Motor Show, the Fiat 1100 Rovelli bodied by Castagna, and the Revelli-Monaco Testadoro 1100, designed by the famous designer Mario Revelli di Beaumont.

Curiosities 

The Testadoro has the curiosity of being a car driven by three illustrious protagonists of Italian automotive design: Mario Revelli di Beaumont, Elio Zagato, and Nuccio Bertone.