Born: 2nd January 1885, Geneva.
Died: 9th December 1950, Paris.
Ernest Henry was a Swiss engineer and the man who made a big leap with internal combustion engine technology – he developed the first double overhead cam engine!
He studied engineering in Geneva before working on marine engines for a company that made a variety of products including bicycles, motorcycles, cars and boats plus their own version of a Mercedes style radiator. The company was run by two brothers, one interested in the land vehicles and one into marine products. When the marine boss, Charles Picker, relocated to France due to a large volume of boat orders, Henry went with him to Paris to continue with marine engineering. However, soon after arriving in France, Hispano-Suiza in Spain ordered a batch of engines for their smaller racing cars and Henry converted them for this use. They were T-head engines producing about 45hp.
Peugeot saw Hispano-Suiza’s success and in 1911 hired Henry and bought some of the Picker engines for their own racing team. By this time, Peugeot (the company) was already 100 years old and had been making cars for nearly 20 of them!
At this stage of the evolution of the car engine, L head (also known as sidevalve or flathead) engines were very common due to their simplicity and cheapness to manufacture. Overhead Valve engines had been around for around 13 years and were popular for early sports cars and the Single Overhead Cam engine had been developed in 1902 for more expensive road and racing cars.
Henry and his team decided that they would use the Picker T-head design as the foundation of a much larger motor. Henry’s ideas centred around improving this motor by combining several ideas into what would become known as the “Henry System”: multiple camshafts, inclined valves, a cast monoblock to house the pistons and a central spark plug per cylinder. For the Peugeot racing engine, the T-head had evolved into the first Double Overhead Cam, 4 valve per cylinder motor with hemispherical combustion chambers. The motor was a V4 of 7.6 litres producing 175hp through a driveshaft (most cars were still chain driven). It was an immediate success winning the French GP – the ultimate goal for the project, despite losing third gear and having a 20 minute pit-stop! The following year, a Peugeot with this engine won the Indianapolis 500 and with a similar motor took the 1916 and 1919 races!
Incidentally, the Peugeots remained in the US after these races and the ideas were further developed by Fred Offenhauser who went on to claim his own Indy race wins with his own interpretation of the engine design.
Think about what Henry created and the ancestral designs that ultimately came out of it: The Cosworth DFV (Double Four Valve), the Chrysler Hemi and a plethora of high performance 4 valve per cylinder motors. The majority of racing engines use an evolution of what Henry built.
After this success, Henry then did it again for motorcycles and again for Peugeot. He built a 500cc engine using cascading gears (decades before Ducati) and although the motor was powerful, it was also fragile.
Little is known about Henry’s life during the First World War – being Swiss, he was a neutral national and had already left Peugeot. After the war ended, Henry joined Ballot for their attempts at the resumed Indy races and then moved on to Darracq, part of Sunbeam-Talbot-Darracq, for a few years to work on their racers. Pre-war Sunbeam racers had a Peugeot cloned engine fitted, so there was a connection already.
Very little is also known about Henry’s life after leaving S-T-D and working on the short lived Omega car. He had invested in – and created – a factory manufacturing aluminium pistons using European patents of a US design. It seems that other, larger investors forced him out and he lost much of his money (and by all accounts his spirits). It is known that he also helped develop aircraft engines leading up to the second war and then after hostilities had died down, undertook regular engineering work. He died in 1950 still in Paris but in poverty, a state which many engineers found themselves in after their work had become mainstream.
After his death, various books appeared that disputed many of the events of Henry’s life. For example, his son had stated that he never worked for Sunbeam (however Darracq was part of the group) and that his designs were stolen by that company. More intriguingly though, the evolution of the career-defining engine has come under scrutiny with some people suggesting that the engine was actually designed by Marc Birkigt, another notable Swiss engineer, for Hispano-Suiza in Spain whilst Henry was just a draughtsman on the team. The claim is that Henry and others stole the design and sold it (and themselves) to Peugeot before on-selling the perfected design to others. The claim goes further to say that Birkigt sued Peugeot and won, although there is no record of the lawsuit.
Other research undertaken in the early 1970s suggested that Henry had in fact developed the engine for Birkigt and when Hispano-Suiza rejected it, he took it to Peugeot who paid to have it developed further and then they allowed Henry to on-sell the design to recover some costs. One fact that could support this theory is that none of the Hispano cars that competed against Peugeot had a twin cam engine – they still used a single cam motor that Birkigt had designed.
What can be said about Henry is that he covered virtually all transport engineering: boats, planes, automobiles and motorcycles and his designs were certainly the embryos that have grown into today’s technology. It is a pity that so many people disputed his work however the pace of development around that time certainly meant that if patents or other documents were not recorded, it was easy to get confused about who was doing what!
– Auto Racing Comes of Age, Robert Dick (2013)
– Motor Sport magazine (July, 1974)
– The Automobile New York. (September 1912)
Image source: www.delcampe.net