Brake problems
 

I just replaced all the calipers and pads on my 1988 911 Targa. Bled the brakes several times and the pedal still will firm up. I manually pumped them up and bled them, not luck, I pressure bled them, no luck. I had a hard pedal before I changed everything. Checked all the fittings and lines. Any help out there, I am listening!

I recently learned a great trick with bleeding brakes (still learning at 50!). Always bleed the caliper the furthest away from the master cylinder first. And then the trick I learnt if you have problems is to clamp the hoses on the calipers you are not working on - it works brilliantly. We had problems bleeding the brakes on my dad's MGTF, and clamping the hoses worked a treat.

Good luck

I have had similar problems to what you describe (changed components and was unable to get a firm brake pedal after struggling with many methods over the course of many hours & days) - you are likely not getting the air out of the system even though it seems impossible that there is any air left in there.

The method I describe in post #20+ of this linked thread ended all of my "can't get the air out" problems -

http://forums.pelicanparts.com/porsche-911-technical-forum/856730-brake-bleeding-help-needed.html