Porsche Panamera Turbo S E-Hybrid Executive: Let’s unpack all that. Porsche is famous for sports cars. The Panamera is therefore sporty, but with four doors. Turbo S badging indicates it’s the most powerful Panamera in the 18-model lineup, the flagship of the fleet. Now things get tricky. The E-Hybrid bit means this 680-hp Porsche can silently glide 14 EPA-rated miles on pure electric power. And the Executive badge means a stretched wheelbase that delivers rear-seat legroom rivaling an S-Class Mercedes.

A sporty limousine with the efficiency of a hybrid: on paper, this big Porsche adds up to a boiling mass of contradictions. On the road, however, it’s a car that’s greater than the sum of its parts.

We’ve covered the Panamera in detail since its launch in 2016, but to quickly recap, it rolls on the Porsche-developed MSB platform that also underpins the new Bentley Continental GT. The Turbo S E-Hybrid powertrain delivers its 680 hp and 626 lb-ft of torque to all four wheels by way of a 550-hp twin-turbo 4.0-liter V-8 under the hood and a 136-hp e-motor mounted between the engine and the eight-speed PDK twin-clutch transmission.

Select E-Power, and the sophisticated powertrain control system enables the big Porsche to be propelled solely by the electric motor when there’s sufficient charge in the 14.1-kW-hr battery. Hybrid Auto mode automatically shuffles between the internal combustion engine and the e-motor to deliver optimal efficiency. Porsche’s traditional Sport and Sport Plus modes are anything but traditional in the E-Hybrid. In Sport mode the battery charge is always maintained at a minimum level to ensure the e-motor can support the internal combustion engine. In Sport Plus mode the battery is charged as quickly as possible to allow the e-motor to help deliver maximum performance at all times.

Drivers can also instruct the system to preserve the charge in the battery to ensure the car can be driven solely on the e-motor at their destination. Or they can direct it to completely recharge the battery on the go by allowing the internal combustion engine to produce slightly more power than is needed to drive the car.

As befits the flagship model, the Panamera Turbo S E-Hybrid comes loaded with goodies, including a panoramic sunroof, four-zone climate control, and a 710-watt Bose sound system. Standard chassis hardware includes air suspension, 21-inch wheels, ceramic brakes, and the full complement of Porsche ride, roll, torque vectoring, and traction control systems.

The Executive specification—not available on the Panamera Sport Turismo—adds 5.9 inches to the wheelbase, along with standard rear-wheel steering, adjustable rear seats, and soft-close doors. Base price is $194,800, and, incredibly, even at that price features like adaptive cruise control are optional ($2,890). Other pricey extras fitted to our tester included the sports exhaust ($3,490), larger rear center console ($3,180), and the 1,455-watt, 21-speaker Burmester High-End 3D Surround System ($5,190), bringing the total price to $222,100, including destination. Ka-ching!

Limos are all about the rear seat. The low-slung Executive is not quite as easy to get into and out of as a Bentley Flying Spur or Benz S-Class, but despite the low roofline, there’s plenty of head- and legroom. It’s strictly a four-seater, however, the rear passengers sitting low down either side of the prop shaft, separated by a fixed center console. That’s mainly for packaging reasons, but Porsche engineers say the low H-point also means rear-seat passengers are less likely to suffer motion sickness should the driver choose to get all Walter Röhrl on a winding road. Which is entirely possible…

Porsche claims a 0-60 time of 3.3 seconds for the 5,313-pound, 122.0-inch-wheelbase Turbo S E-Hybrid Executive, though given the blistering 2.8-second 0-60 time returned by the Sport Turismo version of the Turbo S E-Hybrid we tested last year, that number may be on the conservative side. Even so, a 3.3-second 0-60 run would make the big Porsche quicker than the 603-hp, 5,105-pound, 124.6-inch-wheelbase Mercedes-AMG S 63 we tested last year, and—on Bentley’s own numbers—the 626-hp, 5,456-pound, 120.7-inch-wheelbase Flying Spur W12 S. The Porsche’s claimed 192-mph top speed shades the 186-mph terminal velocity of the S 63 but is beaten by the Bentley’s 202-mph top end; though anywhere other than on a German autobahn, these numbers are the stuff of country club cocktail hour boosterism.

Yes, it’s quick. But where the Panamera Turbo S E-Hybrid Executive really throws down in the sporty stakes is in the twisty bits. Taut body control, quick steering, sticky tires, and a low seating position make the big Porsche feel two sizes smaller than it really is. There’s none of the deliberation, the slight “do you really want me to do that?” moment you experience in the S 63 or the Flying Spur when hustling those big, fast sedans down a winding road. The Turbo S E-Hybrid simply reacts, grips, and goes.

It comes close to squaring the limousine-as-sports-car circle, this Porsche. Leave the suspension in the standard setting, and the air springs and long wheelbase serve up a ride that’s calm and poised, both around town and on the freeway. And it remains just as composed through the corners, staying flat with no diagonal pitching over midcorner heaves. The rear-wheel steering—which can turn the rear wheels up to 2.8 degrees in the opposite direction to the fronts to effectively shorten the wheelbase—helps the big Porsche deftly dance through tight turns.

But that poise and agility comes at a price: tire noise. The low-profile Michelin Pilot Sport 4 tires roar like a freight train through a tunnel on coarse tarmac at freeway speeds, and there’s some slap-patter over road acne around town. With an interior wrapped in leather and Alcantara, dripping with the latest in touch-tech and designer jewelry, the long, low, lavish Turbo S E-Hybrid Executive is dressed to the nines. But you’re always aware it’s wearing sneakers with the tux.

The Turbo S E-Hybrid is thus arguably still more Porsche than limousine, but there’s no question it’s both powerful and efficient. The performance numbers tell the power story. Efficiency? An 1,835-mile road trip from Atlanta to New Orleans, Savannah, Charleston, and back saw the big Porsche average 24.1 mpg. And that was achieved with only one full charge put into the 14.1-kW-hr battery, in Atlanta at the start of the trip.

With the powertrain set in Hybrid Auto mode, the Porsche’s electronic brain managed the battery charge and the e-motor’s contribution to our progress the whole trip. Once the battery is depleted, the system uses the internal combustion engine to bring it back to a 5-percent charge. It then uses that charge to enable the e-motor to provide torque fill under acceleration or to power the car on its own for brief stints of light load cruising (the Panamera E-Hybrid can run at up to 86 mph on pure e-power).

The system also allows coasting, shutting down the internal combustion engine when you lift off the gas. There’s very mild liftoff regen (to help increase the distance coasted) but more intense levels of regen under braking, which helps feed the battery in stop-and-go traffic.

To make you feel like a true eco-warrior (despite the fact you’re driving a 17-foot-long luxury car) the E-Hybrid trip computer shows the time and distance it has traveled without the 4.0-liter V-8 running as “zero emissions” values. And all those little e-motor interventions and coasting intervals and regen events add up: Over 1,700 miles, the trip computer showed we’d clocked up 300 miles of zero-emissions running.

Whether cruising at 70 to 80 mph on the freeway, cruising a quiet back road, or mooching around town, the big Porsche returned impressively consistent fuel consumption numbers, with a best of 25.0 mpg and a worst of 23.1 mpg. For context, the official EPA numbers for the Mercedes-AMG S 63 are 17/26 mpg city/highway, and for the 12-cylinder Bentley Flying Spur, 12/20 mpg city/highway. The 2018-model-year Panamera Turbo S E-Hybrid Executive is rated 21 mpg combined city/highway when just using the engine, and 49 mpg-e combined city/highway using the hybrid system.

The Porsche Panamera Turbo S E-Hybrid Executive offers a unique take on the long-wheelbase luxury limousine. It’s sleek yet roomy, fast yet efficient. Most of all, it’s a long-wheelbase luxury limousine that drives like a Porsche, as edgily suave as a tuxedo with sneakers.