D800 motorsport, what am I doing wrong?

Went to my local motor circuit to try out my D800, was shooting at either 1/160 or 1/200 at F/11, the cars were almost running across the frame left to right but the front of the cars on most of them seems to be blurred.

I also took some pictures with my 24-70mm f/2.8 Nikon with the same result. Pictures of static objects are pin sharp.
What am I doing wrong?