A Chinese smartphone company now holds the record for the fastest four-door car to lap the storied Nurburgring Nordschleife, a 20.8km race circuit in Germany used as a yardstick for sports car brands around the world. But there’s a catch, because the car that achieved that lap time isn’t the same as the one it plans to sell to customers for road use. The SU7 Ultra, an electric car developed by the smartphone manufacturer Xiaomi, is the high-performance version of the Xiaomi SU7 sedan, the same car Ford CEO Jim Farley this month admitted he’d been driving for six months in the US and that he “d…