I need a FUE transplant with about 4000 grafts. Is my donor good enough? (Photo)

In response to your question you seem to have a more than adequate donor area for 4000 grafts. You would need a consult to determine extent of hair loss as well as managing your expectations.

There's no way to tell you for sure whether or not your donor area could support donating 4000 grafts. It does look like you have a fairly normal donor area though, which generally would mean you could probably give over 5000 if necessary. However, you should have an in person consultation (or several) to know for sure.