180V and 150V are of no significance right now - one can assume it is the applied stroke inside the booster. The dbao/choro is brake bleed - we are not discussing that what I am discussing is the actual booster itself, it has a pin on the side of the master cylinder - this pin pushes the cylinder piston in when you apply the brake, this pin is adjustable too - it has to have no clearance to the master cylinder apply piston when installing. Any clearance here results in play in the lever.
Another problem causing dead pedal feel is wrong bleeding of the brakes, the brakes should be bled with a catch bottle on the wheel slave cylinders - the bottle should be placed in a way that the liquid goes upwards from hub - but the entire setup should be below the master cylinder level in the engine room.
check this thread - you will understand the concept.