Thanks to the rear-axle steering which is fitted as standard, everyday practicability and performance have both been equally increased. The system consists of two electromechanical actuators fitted on the rear axle instead of the conventional tie rod. It therefore steers the rear wheels of the 911 Turbo models around up to 2.8 degrees in the same or opposite direction as the steering angle on the front axle, depending on speed.
At speeds up to 31 mph the system steers the rear wheels in the opposite direction to that of the front wheels. This has the virtual effect of shortening the wheelbase. The turning circle is reduced, steering into corners becomes much more dynamic and parking is noticeably easier.
At speeds above 50 mph, the system steers the rear wheels in the same direction as that of the front wheels. The result is a virtual extension of the wheelbase and increased stability, for example when performing high-speed manoeuvres on the motorway.
Between 31 and 50 mph the steering direction is constantly changing depending on the driving conditions.
Thanks to the excellent stabilizing properties of rear-axle steering, it has also been possible to make the steering ratio on the front axle more direct around the central position. The advantage is greater agility without any loss of stability at higher speeds.
The flexibility of the rear-axle steering makes it clear that there is no contradiction between stability and agility, performance and everyday practicality. The result is greater manoeuvrability in day-to-day driving – and a clearly noticeable increase in maximum performance.