HONDA The Power of Dreams

The RA273E was developed in accordance with the 3L engine regulations that started in 1966, and powered the Honda F1 team for two seasons until 1967.

Although the new F1 engine regulations, which lasted for 21 years until 1986, allowed the entry of 1.5L supercharged engines as well as 3L naturally-aspirated (NA) engines, it was only in 1977, 11 years after the regulations were inroduced, when the first turbo-charged engine was introduced. During this time, F1 was in an era of multi-cylinder engines, including V8, V12, H16, and horizontally opposed 12-cylinder engines.

Honda continued with its basic configuration of V12 DOHC 4-valve from the 1.5-liter era, resulting in the 3-liter RA273E. The published specs are 2992 cc with a bore x stroke of 78.0 x 52.2 mm, maximum output of over 400 hp at 10,500 rpm, and engine weight of 230 kg.

The bank angle of 90 degrees, unusually wide, was chosen for the best matching of the engine to the chassis and for greater freedom in the layout of the exhaust system. The RA273E was not transversely mounted as its predecessors, but had a more orthodox longitudinal mounting, as it was not practical to mount a 3L V12, with twice the displacement, transversely. The RA273E, which produced more than 400 hp, was the most powerful engine of its generation, with a high output at high rpm that overwhelmed rival engines.

It was, however, a large and heavy engine due to the use of excessive mechanisms for durability and reliability, as seen in the assembled crankshaft with roller bearings. The chassis of the 1966 RA273, which was powered by the RA273E, was also large and heavy due to the pursuit of strength, rigidity, and reliability.

Although the RA273 was powered by an extremely powerful engine, its power-to-weight ratio was on the same level as that of its rivals. The car was able to finish races in the top positions, but it had a major problem of being large and heavy, and was unable to overcome this problem with engine power, so the championship remained out of reach for many races.

However, the RA273 and RA273E were not all about rationality. This was their strong individuality and greatest appeal. The sight of the Honda F1 cars, with their ferociously powerful engines, large and heavy bodies, and ultra-high speeds, attracted fans from all over the world.

The RA273E debuted in 1966, and continued to compete the following year with various improvements. The 1967 version of the RA273E featured a 17 percent reduction in weight to 190 kg, with a magnesium alloy cylinder block (instead of aluminum), and a redesigned gearbox to reduce size and weight. In order to develop a new fuel injection system, the team decided to miss one race in July, and in August, the exhaust manifold was drastically reshaped. The announced output rose by 20 hp to over 420 hp at 11,500 rpm. The car’s appearance also changed dramatically, with the exhaust manifold rising from the center of the V-bank like horns. Together with the tightened ram pipe shape of the fuel injection system, the car looked more fierce.

In Round 9, the Italian GP in September, the RA273E, powering the new compact and lightweight RA300, achieved its long-awaited first victory. Driven by John Surtees, this was Honda’s second F1 Grand Prix win, which pushed Surtees up to overall 4th in the drivers’ standings, and Honda up to 4th in the Constructors’ Championship alongside Scuderia Ferrari.