Gallery: Upcoming 2020 McLaren Speedtail testing wraps with speedy 403kph run!

The 2020 McLaren Speedtail is ready for production, having topped 400kph at the Kennedy Space Centre in its final test.

The production-ready 'Hyper-GT' hit 403kph with Kenny Brack, chief McLaren test driver, behind the wheel. It wasn't a one-and-done effort, either. McLaren says the Speedtail hit its top speed more than 30 times on the space shuttle landing runway in Florida.

Power in the car comes from a 4.0-litre twin-turbo V8 hybrid, that’s combined with a small 5.2kW lithium-ion battery delivering 1,150Nm of torque to the rear wheels, good for a 300kph sprint time of just 12.8 seconds...

Although that prodigious powertrain is part of the equation, clever aerodynamics are at the core of this car's performance. The body is made entirely of carbon-fibre (dry weight is 1,430kg) and measures 5,137mm long, with a teardrop shape when viewed from above.

McLaren hasn't bothered with mirrors, instead opting for pop-out cameras that hide away when the car is switched off, and the front wheels are finished with (very cool) carbon-fibre aero covers.

And there are almost no cutlines to disrupt the airflow, with a huge one-piece clamshell covering the rear end.

The entire interior of the McLaren Speedtail has been designed to cosset and embrace the driver and their passengers, with the finest hides enveloping almost every surface.

The driver's seat on the Speedtail design model is trimmed in Dark Glacier and Cool White leathers, the former a full aniline material and the latter a new, semi-aniline lightweight leather, developed by the Bridge of Weir Leather Company.

Even though it is super quick it is still 17kph slower than the Bugatti Chiron hypercar’s 420kph top speed...