having difficulty with my brakes... cant get rid of the softness in the pedal. the front is disc and rear is drum, i have bled the system several times, put a new master cylinder in, taken the drums apart to clean and still cannot get the pressure i want. the engine does not bog down when the brakes are applied(which if it did would mean a vacuum leak) but if you pump the brakes when coming to a stop they firm up???! could there be something with my disks up front causing this or something else possibly being the culprit? any help would be great!

more than likely there is brake material deposits and uneven wear on the rotors, this causes the pads to be pushed further away from the rotor surface during times of no brake useage, then when you depress the pedal the caliper pistons have to travel much further than normal requiring you to pump the brakes to get a solid brake feel.

If you decide you want great brakes then upgrade to 4dr sidekick rotors and calipers up front!

Check the above, this is what most people refer to as "rotor warp". Also, did you take the calipers apart ? sometimes the little slider pins the the caliper rides on get seized up.

If its neither then maybe your brake lines are expanding ? How old are they are they /are they the stock rubber ones ?

If that checks out I'de be back to the master cylinder. Did you bench bleed it ? You can also bleed it in the car at the connections if not.     

I have had this problem several times.  there are two very common possible issues.

1. Bad rear brake shoe auto adjuster.
2. Bad rear wheel cylinder