I still have a very low pedal and not much braking power. What has been done so far on a 79 Blazer. DIY4X rear caliper mounts. Reman calipers, proportioning valve from Shane at blackwidowperformance,3/4 ton MC, lots of bleeding. One of the front calipers is a newer reman, the other is older. Even when you pump the pedal, the braking force does not increase. The pedal never gets hard. The pedal is a little higher without the engine on, which is normal. The booster makes a little noise when you push the pedal, but I am under the impression that if the booster went out, the pedal would be harder to push. The truck does not dive to one side or anything. I need help guys. I am out of ideas.