power brakes, 57 buick special

I know my car has power brakes, was wondering if there is a way to test the performance of the vacuum booster? A way to see if it is doing everything it is suppose to do?

Pretty much seat of the pants, does the pedal hiss or hear a vacuum loss when held in the boost position, it is a vacuum booster correct? Does the assist feel adequate driving? Engine off, pedal should be hard then when started go to a normal height.

If it's the old Bendix Treadle-Vac booster and cylinder, it will make noise when the pedal is depressed, and will not necessarily hold vacuum when the engine is off.

Pretty much seat of the pants, does the pedal hiss or hear a vacuum loss when held in the boost position, it is a vacuum booster correct? Does the assist feel adequate driving? Engine off, pedal should be hard then when started go to a normal height. Thanks for the info......looks like I will need a new booster, now just need to figure out where to get one????

Thanks for the info.. looks like I need a new booster, any good places I can purchase from? Reliable and good prices...

Try Napa, they may still be able to one, then get a Hemmings News, plenty of advertisers there.