Background: 66 Lark, originally single resevoir master cylinder/booster with drum brakes. The booster shot craps so my uncle and I replaced it with a "Corvette" style (his words) dual resovoir an 9inch booster which was brand new in the box. It was bench bled and the brakes worked great for 2 years. The Lark has sat for 8yrs since then. I've rebuilt the wheel cylinders, replaced the front brake hoses and bled d@mm near a quarts worth of fluid through the lines. I double checked that all lines and bleeder valves are tight. I also removed the vacuum hose to the booster, inspected it, passing muster, I reinstalled it. The pedal still goes almost to the floor and barely stops the car. I also inspected for leaking lines, none. Any ideas?