Slow Brake Pedal Return at Speed???

Hello everyone,
I built a '32 3 window on new frame rails and have a weird problem. I have a Summit Racing master cylinder/booster combo with Pete & Jakes pedal setup. Discs front & rear with 2 Lb. residual valves. The brakes work fine at slow speed around the neighborhood but when I apply the brakes when going 30 MPH or above the pedal stays down and the brakes are still slowing the vehicle down with my foot off of the pedal. It's like they are on automatic. After a few seconds the pedal returns and the brakes release. I have a feeling it's the residual valves but it only does it at speed.
Thanks for your consideration.
Gary

 

Gary: Post your question here, you'll get a greater response:
https://www.jalopyjournal.com/forum/forums/the-hokey-***-message-board.5/

 

Welcome and good luck, I’m sure you’ll get an answer here.