90 years of the Autocar road test: Design and engineering

The four-valve cylinder head was seen as a powerful marketing tool in the 1980s, when a ‘16v’ badge on the back of a Mk2 Volkswagen Golf GTI added sexiness to the car.

Yet multi-valve heads were old hat by the time Autocar started testing cars in 1928. The Stutz Bearcat used a multi-valve head in 1916 and both Bentley and Bugatti had four-valve heads.

Fuel injection is another technology that gained glamour status at the hands of marketeers in the 1980s, but it had been around for decades. Like many advances, fuel injection was pioneered in aviation, where mixture control is more complicated due to extreme altitude changes. The first petrol injection system appeared on a LeÃon Levavasseur-designed aero engine – the first V8, no less – in 1902. Bit of an unsung hero, Monsieur Levavasseur.

The Mercedes-Benz 300SL (road test 1560) is often credited with being the car that introduced fuel injection to the public highway, but the two-stroke Goliath GP700 that arrived in 1952 got there three years earlier using a system developed by Bosch.

Nothing quickened the pulse of the 1980s road tester more dramatically than a dose of forced induction, more specifically turbocharging. But the use of engine-driven superchargers goes back to the beginning of the internal combustion engine’s life in the 1880s. Our 1928 road testers got their first taste of supercharged horsepower with the Mercedes-Benz Model K, which used a blown 6.3-litre straight six making 160bhp.

Turbochargers are almost ubiquitous today but the technology took longer to take off – and an aviation analogy is apt, because turbochargers were first used on aero engines in the 1930s. The development of turbochargers carried on through World War II, with the first appearing on a production car on the Oldsmobile Cutlass Jetfire in 1962, although Europe had to wait until 1973 for BMW’s 2002 Turbo.

Cool as it was, the 2002 didn’t quite have the impact on the schoolboy senses as Porsche ’s 911 Turbo, which was launched a year later at the Paris show. The words ‘Porsche’ and ‘Turbo’ pretty much defined high- performance motoring in the 1970s.