Technically this can come down some. The max speed in the game is 299. I don't think the Zonda maintains that after the NOS wears off. Setting a tune would let you drift that final stretch in 5th and go faster than 250. Might have an issue with the last train being in the way though. Depending on how wide the finish checkpoint is you might be able to arch around it. Drifting in MC3 doesn't require the back and forth MC2 does.