When I first start the car up, my brakes are low. Then when the car runs a bit the seem to pump up. I do hear a whosssing noise when I press the pedal. But after It runs for awhile it goes away. Also my rear brakes dont seem to be that strong. I might add that the car had sat for 7 years and that I changed the front to rear line, one rear axle line and the passg. side wheel cyl.. Any help would be welcomed thanks. Oh it might help by saying this is going on in a 88 camaro... Thks again Clarence