One of the sweetest tech features Porsche introduced on the 991 911 GT3 (and Turbo, for that matter) is the active rear steering. However, the steering angle is extremely limited, so you won?t quite be able to tell the system is doing its thing just by looking at the car as it passes.
When the speed stays below 50 km/h (mph), the rear wheels move in the opposite direction of the front ones. The effect is that the car handles as if its wheelbase had been shortened, making the sports car easier to maneuver. Once you go past 80 km/h (mph), the rear wheels turn in the same direction of the front ones, making the car more stable.
Powered by a six-cylinder 3.8-liter boxer engine developing 475 HP (349 kW) and 438 Nm (324 lb-ft) of torque sent to the rear wheels through a dual-clutch seven-speed gearbox and a locking differential. It will do 0-62 mph (0-100 km/h) in 3.5 seconds and can achieve a maximum speed of 195 mph (315 km/h).
Here is a small demonstration of active rear steering wheel
2014 Porsche GT3 active rear steering demonstration - Video Dailymotion
[video=dailymotion;x1grcy2]http://www.dailymotion.com/video/x1grcy2_2014-porsche-gt3-active-rear-steering-demonstration_travel[/video]
Credits:Worldcarfans.com