Does the pedal get hard with multiple pumps holding the pedal down on the last one?
If no still spongy, then you got air somewhere.
If yes it gets hard, then you have either flex in the system, or excessive travel somewhere.
But if nothing makes a difference check your Compensating port operation.
This is not rocket science; a hard pedal means no air regardless of how many pumps it takes. A spongy pedal always means air in the system or rotten hoses.
Lots of pumps then hard, means one of three things; excessive travel somewhere, insufficient M/C stroke capacity, or flexing calipers.
And won't get hard no matter what, usually means the C-port is not compensating. If it ain't working, then it ain't moving fluid, and then nothing works.
The statement that you bled it 50 times points to a working C-port, else no fluid would have come out during the bleeding procedure. S you are already ahead of the game
If you have drums in the back, then go look for excessive travel back there. If it is not readily apparent, then remove the shoes and but a HD C-clamp over the wheel cylinders in such a way that the pistons cannot come out of there; then pump the pedal again. Does the pedal get hard now?
If yes then fix the back brakes.
If no, then go look for flex in the front calipers. You might have to take them off and install a metal strap between the pads ; then hit 'em hard with hydraulic pressure, while watching them. Sometimes I C-clamp the pistons into the bores. With both front and rear hydraulics now C-clamped there is no excuse for not getting a hard pedal........ on the first pump, actually, probably immediately on pedal application!
