I got a bit mixed up. One of the initial barriers they had in development of this car was with the spoiler in position they couldn't get above 230mph. So they developed a system where you can put a key in the floor (!) which lowers the car another couple of inches and locks the spoiler so it won't deploy. You can't turn, but you can get up to 253mph.
Gotta love those W16 engines.
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