You want to go how fast? Just give up on the idea of really chasing the shadow unless you have a jet airplane. Then the problem is one of a view. Modern passenger jets have terrible windows for eclipse viewing, you can only see a small patch of the sky and ground below. While spell binding, it is kind of frustrating. Real eclipse chasers sit tight and let the shadow come to them.

(c) Eclipse Nuts Cartoon by Bill Kramer. Uploaded Mon, 27 Mar 17 11:26:19 -0400