BabyGT

Figured this was the best place to ask this question since we don't have a brakes section and it is on a 351w. It's actually in a bronco but a fords a ford I guess.

My problem is with the cam my dad had put in this 351 years ago under hard braking the brake booster kills the vacuum in the motor and stalls it out. I've already made my vac reservoir and am ready to install it but cannot wrap my head around what direction I need to install the check valve between the motor and the reservoir?

I've tried looking at pre made vac reservoirs, but they are either made with the check valve molded in or designed so it can only be connected one way with no indication of the air flow.