The Porsche 911 must be one of the world’s best adverts for the power of continuous product improvement. Through nearly half a century of refinement since it was conceived as a larger, more comfortable successor to the Porsche 356 and was powered by a 2.0-litre, 128bhp flat six engine, this effervescent sports car has kept up with the standards of the market’s freshest performance machinery. Technologies such as fuel injection, turbocharging, four-wheel drive and, most famously, moving from air to water cooling have been integrated. All the while, its legendary and utterly beguiling motive character has survived undimmed.