The maximum speed that we can see is 250mph which is 402.317348km/h.
However, in the stats if you're at max speed for long enough it will blip into 251mph (403.926617km/h).
It's the maximum speed in the game completely.
However, if we based it all on stock, then yes the Zonda is indeed the fastest.
Status = Part Time. [b][color=red][size=12]I am the car expert! So I've been told. lol[/b]
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