Power steering overrun - lack of flow or worn box?

chrgdrt said
I used to run into that problem in my 68 that had the federal pump. I currently have a 67 that I converted to ps using a Saginaw pump and have not had that problem so I’m going to say it’s a pump problem, not enough flow.

I agree with this.
What also helps is to add an inline cooler like this:

DB 260.JPG

This one I mounted on the frame rail below the battery tray.

DB 258.JPG