Several ways to deal with this.
1. do you have power brakes?
2. almost all disc are power, but they don't have to be. A stick car can be converted with a different master to give good pedal pressure.
3. the amount of cam that kills a vacuum boost is a variable, with compression a major factor. The brakes still work (on stored vacuum), but only once with boost (after that, they work but the pedal is very hard), and need a brief interval of engine vacuum to boost again.
An extra vacuum can in the hose allows several more stops.
An electric pump cures most of the problem (but it will cycle continuously in heavy traffic). More details, read my article:
http://victorylibrary.com/mopar/pump-tech.htm
