I did a junk yard disk brake conversion. 72' monte carlo. I am using my metering or distribusion block, and I am using a adjustable por. valve for rear bias. all new parts except for my metering block. my brakes are crap. soft pedal, it takes two or three pumps two firm up. master has been removed and bleed twice. brakes bleed several time using the two people method and vaccumed pumped. with air only being removed when the master was removed and reinstalled. what gives?? do I have to replace my metering block? I thought you could keep it. I just read you had to fix the rear bias difference problem. thanks for any help.