In keeping with the overall concept of the Panamera Sport Turismo, the chassis also combines the ride comfort of a luxury saloon with the performance of a sports car. This is achieved by a range of innovative chassis systems that supplement the superior basic layout: with rear-axle steering, Porsche has brought the steering precision and handling of a sports car to the luxury segment. The wealth of chassis systems also include adaptive air suspension with three-chamber technology including the electronic damper control PASM (Porsche Active Suspension Management), Porsche Dynamic Chassis Control Sport (PDCC Sport) including Porsche Torque Vectoring Plus (PTV Plus) and electromechanical steering. The integrated Porsche 4DChassis Control also analyses and synchronises all chassis systems in real time, thus optimising the handling of the Panamera Sport Turismo.
Compared to the sports saloon, the new Panamera Sport Turismo allows an even higher load weight. Porsche has therefore adjusted the brake system of the new model, and increased the size of the brake discs on all versions: The front brake disc diameter is 390millimetres, while the rear disc measures 365millimetres. For the Panamera Turbo Sport Turismo, the discs measure 410millimetres (front) and 380millimetres (rear). As with the sports saloon, the Sports Turismo can also be ordered with the Porsche Ceramic Composite Brake (PCCB), which has been tried and tested on the race track. Some 50per cent lighter, the diameter of these extremely durable discs is 420millimetres (front) and 410millimetres (rear).
Balanced and tuned axle concept as the basis
At the front of the Panamera Sport Turismo, Porsche uses a double-wishbone suspension with forged aluminium wishbones and hollow cast aluminium lightweight pivot bearings. The axle and elastokinematics ensure optimum agility and precision, while maintaining a high level of comfort. Comfort is further improved by a large-volume, hydraulically damped elastomer bearing on the lower wishbone. The anti-roll bar link on the pivot bearing also enables the use of monotube dampers, which optimise comfort. A screwed aluminium subframe in combination with the electromechanical steering also ensures excellent driving dynamic properties and agile handling. The rear axle uses a lightweight multi-link suspension with forged upper aluminium wishbones and hollow-cast lower aluminium wishbones. Again, the optimised axle and elastokinematics ensure maximum agility and precision with very high levels of comfort. The kinematics also enables the integration of rear-axle steering and the electromechanical PDCC Sport as well as the adaptive air suspension.
Rear-axle steering makes the Sport Turismo as manoeuvrable as a compact car
Porsche also offers optional rear-axle steering for the Panamera Sport Turismo. At low speeds of up to around 50km/h, the rear wheels steer in the opposite direction to the front wheels– variable across the vehicle speed– up to a maximum steering angle of 2.8degrees. This is known virtual wheelbase shortening. The advantages include more dynamic cornering and significantly improved manoeuvring and parking in tight spaces. At speeds above around 50km/h, the rear wheels turn in the same direction as the front axle depending on the on the speed. This provides a virtual wheelbase extension, and therefore increased driving stability when changing lanes on the motorway, for example. The rear-axle steering of the Panamera optimises active safety and driving dynamics, as well as comfort thanks to the reduced steering-angle requirements at low speeds. The use of rear-axle steering also enables a significantly more direct steering ratio on the front axle.
Integrated Porsche4D Chassis Control
Porsche has developed a centrally connected control system for the chassis: 4DChassis Control. Previously, the chassis systems worked largely independently of each other, used their own sensors and responded to the other systems. Porsche 4D Chassis Control analyses the current driving situation centrally in all three dimensions (longitudinal, lateral and vertical acceleration), uses these findings to calculate optimum information about the driving status, and makes this information available to all chassis systems uniformly and in real time – creating a fourth dimension in chassis control. As a result, the systems are able to respond to the imminent driving situation in an integrated manner.
Porsche Active Suspension Management (PASM)
The standard Porsche Active Suspension Management (PASM) is an electronic shock absorber control. It responds to the road conditions and the driving style, and continuously adjusts the damping for each wheel based on this data. Three driving modes are available: “Normal”, “Sport” and “Sport Plus”. The PASM functions as follows: Sensors monitor the body movements such as those that occur during heavy acceleration, braking, fast cornering, or on uneven road surfaces. The PASM then sends the captured data to the Porsche 4DChassis Control. This new command centre calculates the current road condition and regulates the damping hardness of the PASM depending on the driving mode. The 4DChassis Control also coordinates the control parameters of the other electronic chassis systems. The tangible result is increased driving stability, performance and comfort. And the potential of the PASM is even greater in combination with the adaptive air suspension: Since both the damper characteristics and the spring rates can be varied and combined in this case, there is an even greater spread between sportiness and comfort.
Adaptive air suspension with PASM
Four of the five versions of the new Panamera Sport Turismo are fitted with three-chamber air suspension as standard; the air suspension is optionally available for the Panamera4 Sport Turismo. In terms of comfort levels in particular, the adaptive air suspension sets new benchmarks. It has been vastly overhauled compared to the air suspension of the first-generation Panamera. The current system has three instead of two switchable air chambers per spring strut and around 60per cent greater air volume. This enables a considerably larger spread of the spring rates. The chassis can be set to a lower basic spring rate for increased comfort, as the spring rate can be changed electronically in a fraction of a second where necessary – for example, during acceleration and braking or to reduce rolling motion.
The air suspension also offers the familiar advantages of the self-levelling function. In addition to the Normal Level, the system also offers a Lift Level and Low Level. The lift level raises the chassis by 20 millimetres, which can help to prevent damage to the front spoiler, for example, when entering underground car parks. The Low Level lowers the front axle by 28millimetres and the rear axle by 20millimetres to perfect the vehicle position on the road at high speeds and improve the aerodynamics.
Active anti-roll stabilisation PDCC Sport including PTV Plus
In the Panamera Sport Turismo, the Porsche Dynamic Chassis Control Sport (PDCC Sport) optimises the vehicle dynamics thanks to the integration of electromechnical anti-roll bars. The system reacts significantly quicker than systems with hydraulic actuators and stiffens the anti-roll bars to prevent rolling of the body. This active anti-roll stabilisation bridges the gap between the Panamera and sports cars of the calibre of the 911.
In the Panamera, Porsche combines PDCC Sport with Porsche Torque Vectoring Plus (PTV Plus). The electronically controlled rear differential lock of the PTV Plus ensures variable drive torque distribution between the rear wheels, while selective wheel braking interventions generate additional steering torque on the rear axle. The result of this is even more agile steering behaviour. In addition, PTV Plus delivers a noticeably higher level of traction when accelerating out of bends through targeted use of the differential lock. In terms of driving dynamics, the combination of both technologies– PDCC Sport and PTV Plus – puts the Panamera in a class of its own in the field of large saloons.