Brake question

[TechX]

1982 Olds Delta 88 used to be diesel. Now it has gas engine but retains the hydroboost. The brakes were bad when I got it so I replaced mastercylinder,calipers,wheel cyl's,3 rubber lines,5 steal lines. The only lines I have not touched are the 2 going from the master cyl. to the proportioning valve. I replaced everything and thought all those bad parts were my problem. I was shocked when I still had this problem.
To explain the way the pedal feels I would have to say that it feels like there is a spring in the master cylinder actuator rod or something. The brakes feel ok when I stop like a granny but in a panic stop the go to the floor and only have a certain level of resistance. It did this before that after replacing the master cyl. it is still doing it. I do not see how this could be the proportioning valve but maybe the hydroboost is malfunctioning. What are the odds I have another bad master cylinder? HELP!

[jimmy[the]gent]

i bet either there is air in the lines or you are leaking brake fluid some where or both

[MagicRat]

I agree with Jimmy.
There are a couple of ways of bleeding brake lines correctly and about 100 ways to screw it up. Bleed the lines carefully and thoroughly, starting with the passenger side rear

[TechX]

Well due to lack of help/equipment it is very hard to bleed from farthest to closet to the mastercyl. Part of the pedal sponge problem was actually the belt. I took it to Sears and my buddies seen what kinda system it was. They noticed the the belt was not doing its job so I put on a new one first. When I came back they had to pressure bleed the brakes for me. It makes sense that there was also air in the lines but when I started getting all fluid I thought the air was gone. Thanks for the help.