Ok but let´s say you turn at 200km/h
that means you have one big side pushing against the air, while the other side (inside shape) is not vertical but rather angled,
Surely the air as you turn would go diagonally over the arch instead of if you were going straight ahead where the air gets splitted by the very edge of the arch.
I would imagine you would "scoop" up air differently while turning then going straight.
Not sure this makes any sense but when you get some better pics i could photoshop my thinking
The truth will come out...