What shocks are you running.?
Yes,
1) remove federal pump
2) throw away federal pump
3) install saginaw pump with rear pressure oriface drilled 1/64" larger
4) Problem solved
Seriously John Sandburg has been autocrossing his 70 AAR since like 72. And it is a National Championship winning car in C-Prepared car. He always had problems with the Federal pump that came with that AAR. I discovered the Saginaw pump could keep up with autocrossing and has never looked back.
I've had that same problem with the Federal pump that was on my 68 Dart and switched it for a Sagniaw. Perfect ever since. I think I got the Saginaw setup at swap meet or junkard for under $25.