More so now than ever, the entire Cayenne Turbo experience is dominated by that engine. With 4.8 litres (up from 4.5), direct injection and 493bhp (and 516lb ft of torque at 4500rpm), its voice has a harder, tougher edge than before. For a two-tonne-plus SUV, this is a ridiculously quick car.
The last time we figured a Cayenne Turbo, it hit 60mph in 5.4sec and 100mph in 12.9sec, and we thought that pretty impressive right up to the moment when this one popped a 4.8sec run to 60mph and ran into three figures in 11.1sec. That last number is just 0.3sec slower than we timed a 911 Carrera S, for heaven’s sake; it’s quicker even than the old 521bhp Cayenne Turbo S, thanks to its reduced drag coefficient.
Yet there is no great drama in making full use of the Cayenne Turbo’s extraordinary pace. You sit there, looking down upon the world it so successfully cocoons you from, and wait for ever more silly numbers to appear on the dial. And you never have to wait for long.
Use it less energetically, however, and the Turbo provides less than the effortless waft its outstanding statistics might suggest. Throttle response is merely good rather than exceptional. The six-speed automatic gearbox often seems to be working unnecessarily hard to keep the revs up on give-and-take roads, and it’s only when you knock the selector into manual mode (where, correctly, the gearbox will not kick down, come what may) that you realise the high torque peak actually reflects a quite peaky torque curve and an engine that’s happiest working in the upper half of its rev range.
Some will say that’s how it should be for a Porsche, but we would still prefer fewer gearshifts and a greater slug of low-down torque.
In fact, the gearbox is one of the least successful aspects of the Cayenne Turbo. It’s the same six-speed ZF unit used in the majority of large luxury cars these days, but in this application it appears to be less than its usual slick self.