ran new brake lines a few weeks ago, SS front pass and Pvalve to rear. also new MC. yeserday on my way to work after an hour of driving, i had almost no brakes. limpped it home, and am trying to figgure out what the hell is wrong. I flushed the whole system to rule out air with a pump up sprayer i made. checked the master for seal leaks, its dry, checked shoes, nearly perfect adjustment, front calipers are a year or two old and work fine. if i am sitting the pedel is stiff, but once i drive for a miniute it is soft, like maybe the last 20% of the stroke gives me any brakes, but if i pull it back with my foot and pump it 3 or 4 times it gains psi, and gives me good brakes. WTF, i can figgure it out. p valve?