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The boost comes on in a hissing surge, the red needle swings to the right, and one turbocharged Porsche chases another up a mountain. It’s the wild and woolly whale-tailed past and the glossy white future together in a chain, both fast, only one furious. Both are 911 turbos, but only one is a 911 Turbo.

Photos by Brendan McAleer

The slate-grey beast with the enormous spoiler is the true Turbo, a last-of-run 1989 model belonging to local Porsche Club of America president Erwin Kremser. Its air-cooled 3.3-litre flat-six is the original recipe for force-fed Porsche speed, and stands in stark contrast to the technology-crammed power plant tucked beneath the sleek lines of the modern car. Pretty much every Porsche fan knows this car by its internal company code, the 930.

The old car is hairy, laggy, characterful. Kremser hands over the keys with a warning. “Just don’t floor it in a corner,” he says. I settle into the seat and twist sideways to get my feet on the offset pedals. There’s more than a little anticipation here – this car has a reputation for being unforgiving.

Below 4,000 rpm, there’s pretty much nothing going on. Hit four grand on the tachometer and the little red needle reading BAR starts moving right, and the world goes backward. The car pulls like the proverbial freight train, surging forward on a wave of torque. It sounds like a boa constrictor in a fight with a wood-chipper.

From the exhilaration of the ancestor, step into the poise of the descendant. This 2017 C4S has a horizontally opposed turbocharged six-cylinder, too, but it’s a different beast. Displacement is 3.0 litres, with horsepower at 420 and torque of 368 lb-ft. The latter comes not in a surge running to redline, but in a friendly and accessible plateau from 1,700 rpm to 5,000.

Add in all-wheel drive and Porsche’s seven-speed dual-clutch gearbox, and you have a car that even a novice driver could master. This is the fulfilment of the promise made by Porsche’s mid-1980s supercar, the 959. Relentless capability and speed come from the application technology and now, more than ever, that means turbocharging.

At time of writing, the naturally aspirated Porsche power plant is gasping its last breath. Turbocharged V-6s are the mainstream choice in the Macan, Panamera and Cayenne. The Boxster and Cayman, redubbed 718 in an attempt to use a dollop of heritage to sweeten the medicine, are powered by turbocharged flat-fours instead of revvy flat-sixes. And finally, the 911, the brand’s icon, is turbocharged right through the lineup. Only the GT3 RS remains sans boost.

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This leaves Porsche with a branding problem. If all Porsches are Porsche turbos, then what’s a Porsche Turbo? Porsche’s response? Ignore the problem the way everybody else does. A BMW 328i doesn’t come with a 2.8-litre engine any more, and the AMG C63 never had a 6.3-litre V-8 (it was first a 6.2-litre model, now it’s a twin-turbo 4.0-litre). If you see the famous flowing Turbo script on the back of any Porsche, then that just means it’s the most-turbocharged version. Or, to put it another way, the most expensive one.

Porsche didn’t invent turbocharging. The technology was born atop another mountain: the lofty Pike’s Peak, in Colorado. Sandford Moss, head engineer of General Motors, used the thin air at Pike’s 4,300-metre summit to test the application of turbochargers on aircraft engines in the early 1900s. Production turbocharged aircraft engines were in use by the 1920s.

At its heart, a turbocharger is a relatively simple device. The energy of spent exhaust gases is harnessed by placing a turbine in the exhaust flow; that turbine shaft then turns a bladed fan that compresses the air fed into the cylinder. Any internal combustion engine is essentially an air pump, and feeding more air into the system means you can cram more fuel in there as well. More fuel plus more air equals more horsepower without increasing the size of the engine: it’s the replacement for displacement.

Of course, there were and are all sorts of problems with turbocharging. First, look at the lag exhibited by our 930. The turbocharger can only do its work properly once the revs are up and the engine is already pumping out exhaust gases at a decent rate. The solution might be to use a smaller turbocharger, but those can’t pump enough air to feed the engine’s needs high up in the rev range.

Porsche’s experiments with turbocharged racing cars began in the 1960s, and ran to juggernauts such as the 917 prototype endurance racers. Powered by twin-turbo flat-12 engines, these fire-spitting panzerkampfwagens were brutal, fast and dangerous. The final evolution, the 917 Spyder, eventually produced 1,200 horsepower in racing trim.

Encouraged by racing success, Porsche released its turbo technology to the public. The world hasn’t been the same since.

The first cars arrived in 1974, boasting around 260 horsepower in European trim, and a claimed top speed of 260 km/h. Porsche conceived of its most powerful car as a grand tourer, but it could also bite you. Get on the power too early in a corner and the surging power would conspire with the 911’s rear-mounted engine to spin you into the treeline.

Over the years, Porsche worked relentlessly to both increase the power from turbocharged applications, as well as iron out its kinks. Its turbocharged offerings grew faster by the decade, but also grew easier to use. Everything from intercooling the intake charge, to the application of direct-injection, to using variable nozzle technology to squeeze the exhaust flow at lower rpm helped get turbos spooling more quickly. The new Boxster even has something called prespool technology, which gets the turbos spinning before you jump on the throttle.

The result is a modern lineup of turbocharged cars that display none of the violence of its original efforts. This should hardly come as a surprise: You can get a turbo in your family-friendly Ford Escape these days.

What’s heartening is that the 2017 model 911 isn’t completely anodyne. If you flick the drive mode into sport and start using the paddle shifters to select your own gears, it comes alive beneath you, whooshing and rocketing forward. No, Porsche doesn’t brand this machine as a Turbo, but there’s a bit of Turbo under its skin anyway.

Photos by Brendan McAleer