Have a high performance cam in my '79 and is causing vacuum problems
because of set-up I assume. Replace cam, speed is not why I bought , add vacuum pump or change tork converter are suggested solutions. Plan to add A/C and already have brake and idling problems.

Comments and suggestions, please.

I'd try a vacuum canister first and see if that helps, they're less than 50 bucks from jegs.

Some time ago, I began to experience lack of sufficient vacuum to operate the power brakes. Found the vacuum canister that came on my truck had collapsed - from old age I think. I found a generic replacement at a large O'Reilly auto parts warehouse for $11.00 plus tax. Had to Jury rig the installation a little, connected the vacuum line and problem was solved. By the way, get the largest cannister available. That way you will have a maximum vacuum reservoir.