Prototype Mclaren Speedtail Shatters Top Speed Mark Over 30 Times For Definite Proof It’ll Hit Over 400kph

Trying to hit a manufacturer-claimed top speed for your supercar isn’t a straightforward affair. You don’t just start it up and drive to the nearest highway. With top speeds approaching; and now increasingly surpassing, 400kph you’ll sometimes have to take their word for it.

Even then, you’ll need the planets to align and some shavings of a unicorn’s horn. Basically, only under near perfect conditions will it happen. Fortunately, McLaren has proven its new Speedtail grand touring hybrid will easily smash the 250mph (402kph) top speed.

Testing for the three-seater concluded with high-speed acceleration tests at the Kennedy Space Center runway in Florida where the XP2 prototype exceeded 250mph on over 30 separate occasions with test driver Kenny Brack behind the wheel in the central seating position.

Following the conclusion of testing, the Speedtail officially enters production at the Woking, England plant that’s from the future.

The Speedtail’s slippery shape that resembles a teardrop is dedicated to aerodynamic efficiency and is the marque’s most aerodynamic car ever. That massive rear overhang is there for highspeed stability and brings the length to over 5.0-metres. If you’re wondering why there’s no rear wing to keep that end planted, the carbon bodywork incorporates a pair of flexible ailerons that pop up at speed and folds to blend in with the rear when not in use.

It weighs in at 1,430kg and is powered by a 4.0-litre twin-turbo V8 with an electric motor hanging off it. Total output is 1,035hp and 1,150Nm of torque. To hit its 250mph top speed, the Velocity mode drops the height by 1.4-inches.

“It’s fitting that the Speedtail’s high-speed test program concluded with multiple maximum-speed runs at a location so strongly associated with pushing the boundaries of extreme performance and engineering excellence,” said McLaren Automotive CEO Mike Flewitt.

The Speedtail completes the brand’s Ultimate Series for now with the rest of the line-up comprising the Senna, Senna GTR and the windshield-less Elva.

Only 106 Speedtails will be built although Flewitt confirms that more hybrids are in the pipeline; including an all-wheel-drive hybrid that could launch to 60mph in 2.3-seconds. It might rip the tarmac off the Kennedy Space Centre runway though.