The problem was that engines were still terribly inefficient. Bentley’s masterpiece, the 8 Litre of 1931, produced only about 200bhp – just 25bhp per litre. Nor were the problems simply a lack of engineering knowledge. The metallurgy wasn’t good enough, nor was the machining process it went through. Petrol quality was a joke compared with what we take for granted today and compression ratios were kept commensurately low to cope.
Some limitations were even self-imposed: in Britain, cars were taxed on the width of their cylinder bores, forcing designers to create inefficient slow-revving, long-stroke engines that were unable to breathe properly because of the valve diameters this imposed.
The 1930s was a decade of consolidation. Supercharging grew more common and German race teams did extraordinary things with it on the track; the Mercedes-Benz W125 got 646bhp from a 5.6-litre engine in 1937, and it would be the 1980s before grand prix machinery made so much power again. On the road, though, engines got bigger and better but remained faithful to known principles.
There’s nothing like a global conflict for giving technology a boot up the backside, however, and none ever proved this point quite so well as World War II. In the air, we entered it with biplanes only to emerge six years later with jet fighters.
By the time the car world was back on its feet in the 1950s, great things had started to happen. Think of some of the greatest and most enduring engines: Ferrari’s Colombo V12, Jaguar’s twin-cam straight six, Chevrolet’s small-block V8 and even Porsche’s flat six: all were designed between the end of the war and the end of the 1950s. This was a truly epic era for engine production.
The best, though? When I think of the engines that mean the most to me, it’s actually those from the 1960s and 1970s, even though there were comparatively few radical innovations in that time. Supercharging had all but died out, while even by the end of the 1970s, turbocharging was very much in its infancy. What we had instead were free-revving, large-capacity, multi-cylinder, carburettor-fed, naturally aspirated engines that howled, screamed, shrieked and seared their uncorked way into our souls. Just look at Lamborghini’s V12 in the Miura and Countach, Ferrari’s equivalent in the Daytona and its flattened successor in the Boxer.