Nearly every exterior panel of the LaFerrari has been designed to generate downforce, so the FXX K builds up from a very good base. With its extra aerodynamic bits, the racer can generate 1,190.5 pounds (540 kg) of downforce at 124 mph (200 km/h).
The FXX K uses a combination of V-12 engine and an electric motor. Total output is stated at 1,035 horsepower and over 660 pound-feet of torque. That's 246 more prancing ponies than the already-insane LaFerrari.
The "K" in FXX K indicates the kinetic energy recovery system, or HY-KERS. This system recaptures braking energy and re-releases it to provide improved acceleration. A Manual Boost button on the steering wheel lets the driver instantly unleash this stored power in an instant of electric thrust.
Aside from wicked power, the FXX K is crammed with electronic aids and go-faster bits. From the suspension to to the electronic differential to a bespoke traction and stability control system, the racer is extensively configurable.
Inside, the FXX K has been outfitted with racing seats and had much of its interior trim stripped to save weight, but the race car doesn't meet homologation requirements and regulations, so it won't be used in competition. Instead, it's part of what Ferrari calls a "Client-Test Driver" program that allows an exclusive set of Ferrari customers to try out the best the brand has to offer at the track.