Recently my drug units have been capped at 20. What does it take to raise it?

Tip the FBN agent in one city repeatedly until you get the message "You seem to understand how this relationship works. I'll spread word that you're good for business."

Shannom, I happen to know of several well-versed players in your own city that would probably be able to assist you. I'd ask around in your own crew first before coming out to the more public forums looking for game advice.

Good luck