touchy brakes
 

hi guys, just installed a vacuum booster in my 93
(my 2nd replacement) my brakes work like never before. at a roll they are touchy. when braking they seem to really perform well but again a touchy feel. i know the pushrod is adjusted proprly as i have less than a half inch pedal travel
im not complaining. i feel like most of my braking is on my front brakes and would like to know what i need to do to verify that my rear brakes are working . freshly power flushed and bled. i may be over reacting because in the 2 yrs I've owned the car the brakes were'nt too snappy all because the previous boosters were defective. so they very well may be working properly.
https://cimg3.ibsrv.net/gimg/www.cor...302c261454.jpg
ive had 11 vettes not sure if any of them felt like these do

While I do not know how to do it, you might try checking the proportioning valve.