I have an 88 CRX Si that I am having a break issue with. When you press the brake pedal it will go almost to the floor (within 4-6 inches) before the brakes start to engage. If I give the pedal an extra pump or two it will engage the brakes sooner and work just fine. This will repeat every time the brakes are used. I have replaced both the master cylinder and the power booster and still have the same issue. The vacuum hose attached to the booster will almost suck your finger nail off so I don't think its vacuum related. The pads on front and the shoe's in back are fine with plenty of pad. Anyone seen this and know the fix?
Thanks,
Joe

Have you bled the complete system? You may have air in the system.

Yes the brakes have been bled both front and back. Once when I changed the master cylinder and again when I replaced the booster.
-Joe

You may have a bad brake cylinder or leaking brake line. You did not say if there was also brake fluid loss. If it is a cylinder you should see brake fluid on the inside of your tire from the leakage.