Ok, so, I did a 4 pot swap on my S5, as well as braided lines, new pads, an dnew rotors, I also replaced the brake booster hose with anew one. We bled them an dbled them and bled them, an dfinally got the ai rrout, and still, the pedal goes down almost to the floor then they work awsome, I then took the booster hose off an dused a peice of vaccuum line, without the little valve liek the stock hose has, and still, sam epedal pressure. Any ideas?

 

you have to move more fluid for the same effect with 4 piston calipers, i can imagine that you were supposed to swap out hte master cylinder as well

 

master cylinder needs to be swapped they are pricey but I can give u a cost if u want one

Dave