A good running stock cam 235 will have plenty of vacuum for power brakes. You cannot use nor need a fuel pump booster for it. The power brake unit has a reservoir built into it with a check valve at the entrance. When you use your brakes you are decelerating & vacuum is at it's highest. You want 3/8 hose going to the booster. There is a filter you can put in the hose that protects the booster. It came on all g.m.,s starting around the mid 70,s.
