Ten things you need to know about the 308mph+ Yangwang U9 Xtreme

Sitting on BYD’s e4 platform, the U9 Xtreme gets a combined system output of 2,978bhp from four electric motors, each of which deliver 744bhp and can spin at up to 30,000rpm. That’s over double the 1,288bhp ‘standard’ U9.

And significantly more than the 2,078bhp Rimac Nevera R and 2,012bhp Aspark Owl too, in case your jaw wasn’t already on the floor. It also means an astonishing power-to-weight ratio of 1,217bhp per tonne.

Crack open the electric motors and you’ll find a stator (the part that generates a magnetic field to create motion) that utilises the world’s thinnest silicon steel in mass production (0.1mm), which helps to increase efficiency and in turn performance.

It also gets an ultra high strength silicon steel rotor (the central moving component), and an aerospace grade aluminium motor housing. Eat your heart out Tim Peake.

The U9 Xtreme is the first production car with a 1,200V ultra high voltage platform, up from the existing U9’s 800V system, which allows for a quicker adrenaline shot of electricity through the platform and in turn, power to the motors.

The system is capable of supporting up to 1000A of current – the same amount that’s used to power some electric trains. 

BYD’s Blade Battery (so called because it arranges the cells into thin blades) uses a lithium iron phosphate chemistry that’s more energy dense than a traditional battery’s nickel manganese cobalt makeup, which has several advantages.

Single cell power density is increased by 170 per cent compared with an 800V system, allowing discharge rates up to 10 times higher than a conventional EV battery. All very technical, but in other words it’ll sustain extremely high current outputs without exploding.

The 1200V platform plays an important role in heat management too, reducing heat generation by up to 67 per cent compared with an 800V system at a matching power output.

Meanwhile the U9 Xtreme’s Blade Battery can support higher power outputs at reduced state of charge – up to 2,414bhp as low as 20 per cent, we’re told. Not that we imagine the U9 Xtreme was allowed to get anywhere near that low.

Its peak energy recuperation rate is more than 700kW too, helping to reduce load and stresses on the mechanical brakes.

The e4 platform’s quad motor independent torque vectoring system continuously monitors feedback from the road, and can adjust the amount of torque delivered to each wheel at a truly rapid rate – over 100 times per second.

By making minuscule adjustments as and when necessary, this helps reduce any loss of traction or slip from the wheels. Because no one wants a spin out at 300mph.

Remember the DiSus-X Intelligent Body Control System that allowed the Yangwang U9 to bunny hop into the air? Great party trick, but turns out it has much more practical purposes when it comes to record breaking top speed runs too.

Essentially a fancy active suspension system, it can apply up to 9kW of bidirectional pressure per wheel and make adjustments up to 500mm per second. This helps to reduce pitch, dive and body roll during hard acceleration, braking and cornering.

The U9 Xtreme gets a carbon fibre front splitter enhancing stability, while the standard car’s giant rear wing has been lobbed in the spare parts bin.

Makes sense: having an ironing board on the back of the car increases drag, which is kinda counterproductive when you’re trying to bang out a record top speed run.

Oh, and let’s not forget the final piece of the puzzle… generous application of the duct tape. Total kerbweight stands at 2,480kg, just 5kg more than the regular car.

Smaller wheels were ordered in, with the U9 Xtreme wearing 20in shoes instead of 21s. Meanwhile at the front it gets bigger 325mm width tyres, up from the U9’s 275mm number, which now match the rears.

They are semi-slick tyres from Giti, featuring a performance-focused tread design that can handle the increased pressures on the tyres at high speeds. Specialist knurling is also used on the rims, along with a high viscosity lubricant, to minimise any slippages during hard acceleration or braking.

It takes nerves of steel to pilot any vehicle at 300mph. The man tasked with the job was German driver Marc Basseng, a serial winner and multiple-time lap record breaker at the Nürburgring.

Marc took just three laps (second time round anyway) to beat the record, hitting 300mph on the first, 302mph on the second, and 308.4mph on his third and final attempt, finally toppling the Bugatti Chiron Super Sport 300+ (304.8mph). The data suggests he could have had it pinned for another second and a half too…