My old brakes used to feel really mushy before I put the FD calipers on. Now that I have the 929 master and the Wilwoods, you barely touch the brake pedal and your bouncing your head off the steering wheel.



I had a sneaking suspicion that my old calipers were sticking or not operating properly. But then again, they had 200k miles on them

Couldn't really soft old brake hoses contribute to a mushy pedal?



Never mind, I see you installed new braided lines. https://www.nopistons.com/forums/pub...1047683664.gif

i looked in the FSM (imagine that https://www.nopistons.com/forums/pub...IR ) and it says mushy pedal can be



push rod between the master and the booster

air in the lines

worn pads

air in the lines

pedal free play

and air in the lines (it does say air in the system more than once!)



so i think i get to pull it apart and readjust the pushrod in the booster, yay for me

i think the booster is bad, which is a new one, but the car has been sitting for like 10years, in a field....

I have a similarly vague problem. My brakes work great, eventually. I can feel brake pressure being applied the first inch or so of pedal travel, then it gets real firm, and stops great. I would adjust the pedal so it was immediately firm, but then the brakes would be dragging. What's up with that? Squishy rubber lines perhaps?

yeah, or old fluid?

i adjsted the pushrod on mine, it helped a bunch, but its still weird. i adjusted the pushrod between the booster and the master

hey cymfc3s, how's the 929 master working for you? I'm interested in doing that too, but not sure what parts are needed...did you need a new booster? Please let me know what other parts are necessary, thanks!

you need an s5 t2 brake booster, or fd. the 929 master wont bolt to the s4 and na s5 boosters.



good news though it does look like the rx8, fd and fc (an 6..) all share the same brake booster to car bolt pattern... so upgrading to an rx8 master and booster might be a bolt in. the rx8 master and booster are like $100 each, new

That's interesting. But it's not really an upgrade. Could be a downgrade if it messes up the stroke/pressure/assist etc.....



I wonder what size bore the rx8 master cylinder is. The 929 is a 1" bore. The S5TII ones are 15/16" bore. I like the 929 master a lot. Full brakes is like 1.5" travel. Then it's rock hard and you get to modulate the brakes based on the pressure/effort you apply on the pedal rather than trying to move it 1 mm more or less to modulate.