Hewland was for a long time a virtually unavoidable name in motorsport circles, as it supplied market-leading gearboxes through the 1960s and 1970s. But did you know that it also dabbled with engines?
In 1972, we caught wind of a secret project at its Maidenhead base to take on the mighty Cosworth in Formula 1.
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We explained: “The design of the single-cylinder ‘slave’ unit engine is said to be more ambitious than any of the power units currently racing but is not a Wankel layout.
"Because the transmission factory has all the necessary machinery already installed for the manufacture of gearboxes, the ‘slave’ unit has presented no great problems of production complications or extra costs, and because the whole project has been conceived within the factory, it has been relatively easy to maintain secrecy.”
It seems likely that this project resulted in the Arrow, a 100cc single-cylinder sleeve-valve engine that Hewland introduced for karts in 1976.
The special thing about this was that it had a built-in primary-drive reduction gearbox with many more gear teeth, meaning that normal-size engine sprockets could be used and the chain wouldn’t waste energy heating up during races.
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A bit of a non story that, with even the description of the reduction gear so vague it being almost impossible to even understand the concept of it - I'd have loved a fuller description of the engine, and perhaps a diagram, I bet a lot of people here don't even know what a sleve valve engine is.
And that's it?!, is that all your going to tell us?, where's the point in that?