The hybrid Porsche Panamera is chiefly aimed at North America, where emissions regulations and a comparative reluctance to accept diesels make it more critical. In the UK it is a fringe seller at best. The hybrid system favours electric propulsion from start up, while at higher speeds there’s a more regular interaction between the petrol engine and electric motor, but the transition from one to the other is absolutely seamless. Push hard and you’re rewarded with an impressive turn of speed.
The 3.6 V6-powered car is hardly asthmatic, having 296bhp, 295lb ft, but it never makes the Panamera never feel that quick. It’s smooth and free revving, but the PDK ’box has to stay very busy keeping the motor on the boil when pressing on.
The V8 is less brutal than the Turbo but for a car that has its roots in the luxury car market the wonderfully linear, accessible delivery from this 4.8-litre V8 is spot on, and regardless of where your performance benchmark sits, 4.8-seconds to 62mph in a 1.9-tonne car is hardly tardy.
The slightly more powerful V8-engined Panamara GTS delivers explosive off the line and in-gear acceleration. Despite giving away 148bhp and 119lb ft to the recently launched sixth generaton M5, the new Porsche is just 0.2sec slower to 62mph than the new BMW at a claimed 4.5sec.
Although our test Porsche Panamera Turbo came without the optional Sport Chrono pack (denying the performance benefit of an overboost function, the fastest gearshifts possible with PDK and launch control), it still accelerated from rest to 60mph in four seconds dead. This makes the Panamera, with one possible exception, the fastest-accelerating saloon in its class, eclipsing the Jaguar XFR, BMW M5 and Audi RS6. On paper, the Cadillac CTS-V will go faster still, but with only the rear wheels driven this will be surface dependent.
Drive a Panamera Turbo and you will not want for extra performance, but if you want to go faster you can - a Turbo S with 543bhp and 553lb ft of torque is available. Top speed is 191mph, which is faintly academic, while 0-62mph appears at the touch of a button, thanks to launch control, in 3.8sec, which is faintly ridiculous for a 1995kg saloon.
The diesel will win a legion of buyers based on its fuel and emissions standards alone, but if you're buying because you are an enthusiast driver, or like your car to have soul, we'd think very carefully before signing on the dotted line. Sure, 247bhp and 406lb ft of torque deliver decent performance, and economy of substantially more than 40mpg impresses, but it's hard to escape the nagging feeling that this is a compromised Porsche.
The brakes, as expected with Porsche, provide excellent initial stopping power and precise pedal feel. However, during track tests the pedal travel lengthened more quickly than we are used to.