Koenigsegg is always breaking records.
Here's the fastest production car record they set in November of 2017. He doesn't lay into the throttle until 180 mph, then shifts into 7th at 220.
https://youtu.be/xj4gar5dKAUThey came to the U.S. to set that record.
They started out with a Ford 302 engine, and still use the same basic architecture for their current engine, but it's all Koenigsegg design at this point. The innovations they come up with is second to none and really sets the standard for hyper-performance cars.
The new Jesko is theoretically a 300 mph car, but they haven't proven its speed yet. Not an easy task to find roads long enough and flat/straight enough to test a car to that speed.