On a damp and wintry day, the Panamera 4S Diesel batted off the conditions in a show of spectacular force, making its two-tonne kerb weight seem as nothing when we attached our timing gear to it.
In terms of outright speed, the car surpasses most benchmarks set by like-for-like grand tourers and can be considered alongside the quickest super-saloons you might buy for the thick end of £100,000.
This V8 diesel Porsche outsprinted the last BMW M5 we figured as far as 60mph and gave the impression that it might even go a tenth or two quicker still in better conditions. Needless to say, it has unflappable traction.
In terms of refinement, the Panamera is as well isolated and quiet as anything intended for a markedly sporting audience.
It’s not the most luxurious GT of its kind, but in the light of other talents, it is a brilliant compromise.
Real-world fuel economy and range is as outstanding as the acceleration. This is a near-43mpg cruiser with a 90-litre tank, capable of more than 800 miles between fills.
That’s a formidably strong hand for any GT, and yet the Porsche plays its cards with a flourish. The twin-turbo V8 has an energetic timbre distinct from that of the Audi SQ7, feeling smooth and settled on part throttle but revving with greater drama and edge.
It’s matched to a quite brilliant automatic gearbox, which operates with superb speed and instant lock-up in manual mode but obliges with smartly and intuitively chosen ratios in ‘D’. That gearbox effortlessly harnesses the obvious strengths of a big diesel and juggles them against the need to deliver a sporting sense of range. It also lets you interact with and enjoy the incredible motor as much, or as little, as you feel like.
One might expect that an obvious compromise of having a big diesel engine in a car such as this might be a shortage of mechanical richness, but the V8’s engine note is quite pleasing: not gruff and not silken but almost tuneful at times.
It makes for a louder idle than an equivalent petrol might have, but it’s the optional 21in wheels and the chassis compromise that define the cruising refinement, which is still good if not outstanding.