GTC Speed is 4.80 m long, 2.19 m wide, 1.39 m tall (with its top on) and counts on a 2.75 m wheelbase. All the power that is available for the superconvertible comes from a 6-litre W12 biturbo petrol engine. Even though the car is very heavy (it weighs 2,485 kg), its powerplant proves to be very efficient. Top speed with the top on is 322 km/h and 312 km/h if the top it down. It also takes only 4.8 s to sprint the car from 0 to 100 km/h.
Besides the stronger engine (the "entry level" GTC is only 560 bhp), GTC Speed is 1 cm lower in front and 1.5 cm lower in the rear in order to have a better handling. Brakes have also been upgraded and, as an option, buyers can choose carbon-ceramic discs, the biggest ones ever fitted to a production series automobile: 420 mm in front and 356 mm in the back. The system also features eight-piston calipers.