When to take MCAT?

So there's a list of all the classes I've taken so far. Next semester (spring 2017) I'm taking physics 1 and physiology.

I'm also planning on taking a summer course, perhaps biochem is what I'm thinking. Then in the fall I'll take ochem 2 and physics 2.

The question is, would I be ready to take the MCAT by September? If that's the case, that means I'll take the MCAT without knowing any ochem 2 or physics 2 material.

Or...

When to take MCAT?