V6 engines have powered everything, from racing thoroughbreds to minivans. Yet, few people know that this popular engine configuration debuted in Italy 70 years ago, at the 1950 Turin Motor Show.
A Balancing Act
The Lancia Aurelia B10's engine resulted from wartime research done by the engineer Francesco De Virgilio analyzing alternative V-angles for a well-balanced, low-vibration V6 engine. Cast in aluminum with iron cylinder liners, the Aurelia's V6 had a 60° angle between its cylinder banks. Its crankshaft rested on four main bearings, and its six crankpins were spaced at 60° intervals for an even firing sequence. The aluminum cylinder heads' two valves per cylinder were actuated via rockers by a single camshaft located in the engine block, driven by a double chain equipped with a hydraulic tensioner.
Due to the low quality of fuels available at the time, the 1.8 liters B10 engine had a decidedly mild tune, with a low compression ratio and a single Solex carburetor. But that would be only the start of a continuous evolution lasting almost two decades.
2.0 Liters Aurelias
The new-for-1951 Coupé B20 GT was equipped with a 2 liters version of the V6, which gave 75 HP thanks to larger valves, higher compression, and two single-choke Weber carburetors. Simultaneously, the saloon B21 and the limousine B15 were offered. Each had its own milder version of the two liters V6 engine, with lowered compression and the same carburetor setup of the smaller B10 saloon, which remained on sale until 1953.
The second series of the B20 GT coupés, built from May 1952, and the B22 saloon introduced a month later were then the last two liters Aurelias.
The B20 offered 80HP thanks to a higher compression ratio and a new cylinder-head with repositioned valves. Curiously, the B22 saloon had the pair's hottest setup, with 90HP thanks to a new cam profile and a larger double-choke Weber carburetor.
2.3 Liters Aurelias
1954 saw the introduction of the Aurelia B12 saloon, a comprehensively redesigned model inside-out that lost some of the previous model's sporting edge in exchange for more comfort and refinement. For this application, a 2.3 liters engine was developed, equipped with a single Solex 35mm carburetor, and good for 87HP.
2.5 liters Aurelias
The B20 Series three, introduced in July 1953, was the first recipient of the larger 2.5 liters V6 that would carry the model until the end of production. The capacity was the result of mating the B12 saloon's crank with larger cylinder bores. Valve diameter was further increased compared to the previous engines and remained the same for all the 2.5 liters Aurelias. The Aurelia B20 GT and B24 Spider were all equipped with a double-choke Weber carburetor, whose model varied over the years, though, as did the camshaft profiles.
Lancia designed the first V6 engine ever but, sadly, would never get to create another one.
2.5 Liters Flaminias
Launched in March of 1957 at the Geneva Motor Show, the Flaminia replaced the Aurelia as Lancia's flagship. Larger and heavier than its predecessor, the Flaminia used a comprehensively revised V6, with "square" bore and stroke measurements. The performance was on the weak side, though, given that the 100 HP engine had to move a significantly larger and heavier body than previous models.
The situation would improve slightly with the Flaminia series two models, introduced in 1961 and rated at 110 HP due to a higher compression ratio.
The customers wanting more speed from their Flaminias were spoilt for choice though, as from 1958 three different coupé body styles, from Pininfarina, Touring and Zagato, were made available.
From 1962, the Touring and Zagato coupés were equipped with three single-choke Weber 35mm carburetors for a peak horsepower of 140HP that, helped by the much lighter and shorter bodies, provided great performance for the standards of the era.
2.8 Liters Flaminias
The first V6 of automobile history received its last "stretch" around a year later, in 1963. Cylinder bore size grew by 5 mm, resulting in a 2.8 liters engine that produced 129HP in single-carburetor form and 140 with the three carburetors setup. With a top speed of around 210 Km/h, the fastest Flaminia was the SuperSport Zagato, equipped with yet larger 40mm Weber carburetors and rated at 152HP. However, this model, together with the Touring and Pininfarina coupés, left the catalog in 1967 without a replacement. The Flaminia 2.8 remained in production as late as 1970 when the last 8 examples left the Borgo San Paolo works in Turin.
Lancia designed the first V6 engine ever but, sadly, would never get to create another one. Following Fiat's acquisition of the brand in 1969, quite a few Lancia models would be equipped with V6 engines, but all were supplied by other manufacturers. Examples include the legendary Stratos, equipped with the Ferrari Dino V6, then the Thema with the French PRV engine first, and the Alfa Romeo V6 from 1992 onwards.