Testing the world’s fastest diesel four-door saloon
The old Pana diesel had an S badge without ever really meriting it. The 4S Diesel merits it. In fact, Porsche reckons that the 4.0-litre, twin-turbocharged V8 lump under the bonnet makes it the fastest 4-door diesel saloon in the world.
The 461bhp peak power figure is impressive enough, but what really gets your attention is the 627lb ft of torque and the fact that you can access that full amount from a surreally subterranean 1000rpm.
Despite weighing in at over two tonnes the 4S Diesel gains speed with an almost disconcerting effortlessness. Only when you look at the speedo do you realise just how quickly you’re going. A serious sports car could keep up with a well-driven 4S, but not much else could.
Porsche Panamera 4S Diesel
Engine: 3.0-litre, V8, twin-turbocharged diesel
Gearbox: eight-speed dual-clutch automatic
Kerb weight: 2050kg
Top speed: 177mph
Economy: 42.2mpg (combined)
CO2/tax band: 176g/km, 35%
The real party piece however is the extraordinarily relaxed cruising made possible by this engine’s apparently bottomless torque. In everyday traffic conditions a driver will become accustomed to the lazy (and almost silent) three-figure spin of the V8. Press on a little to release a diesel rumble and distinctive V8 burble.
With this sort of grunt on tap, an old-fashioned two-speed gearbox would probably have been more than adequate, but instead of that a new dual-clutch eight-speed PDK transmission has been specially built for the 4S. The shifts are butter-smooth while pottering and machine-gun quick in the sportier modes. Hoof the throttle and the box obediently drops a couple of cogs even when you’re in a less urgent mode.
The 4S also gives you a smart cruise control that adapts to speed limits and bends for optimised cross-country travel, the option of air suspension, and rear-biased all-wheel drive as standard.
Unlike certain Audis, the Pana is not massively interested in putting power through the front wheels. You’ll know when it does do that, usually when coming out of a tight turn with power on, when the precise but slightly uninspiring steering will want to straighten. It’s not going to happen often unless you’re terminally heavy-footed, but it is nevertheless a small blot on the report. Despite the rear bias, unsticking the back tyres requires a high degree of driver commitment.
Our car had the air suspension option fitted. Sumptuous in Comfort mode, it provides greater agility and roll resistance as you dial up through the modes via Sport to Sport Plus. You’ll start to feel the bumps, but none of them will bring a squeak of protest from the suspension. An S-Class beats it, but the Pana is a much sportier proposition. It must be placed in the top echelon of deeply impressive ground-coverers.
Porsche has gone to town on the interior too. The analogue rev counter still occupies its traditional spot in the middle of the instrument cluster, but now it’s bookended by a brace of configurable seven-inch screens. There’s a whiff of Audi’s Virtual Cockpit here, even if the Porsche system’s adaptability and user-friendliness aren’t quite on a par.
A big 12.3-inch touchscreen in the middle of the dash controls the visually appealing PCM infotainment system. There’s a lag on Google Map zooming or twisting, and short drivers will find the left hand side of the display masked by the steering wheel, but on the plus side the touchscreen has done away with many of the distracting buttons previously arrayed around the gearstick. A separate touch-sensitive black panel operates the suspension, heated seats and screen demisters. It all looks a lot more modern, but it’s still not easy to find functions while driving.
Porsche says that this is a four-door, four-seat sports car. Certainly, four six-foot adults and their luggage will fit easily inside, and the car’s ability to monster a bendy road or cruise at high speed is genuinely eye-opening.
There’s no getting away from its size and heft, but even so, its versatility and 700-mile-plus cruising range make it a tempting choice. Especially if you can squeeze a Cayman or Boxster into the garage as well.