Agree that changing booster will only change brake feel, how hard you have to push or not, but won't do much to change pedal travel.
I thought my stock S197 had long travel, mushy feeling brakes stock. I was told on this board and others that going to the 4 piston Brembos would not make pedal travel worse (the theory as it was relayed to me, was the caliper was a stiffer material, and had opposing pistons). Well, it did. The brakes work fantastic, ONCE you get enough pedal travel. Many who upgrade to larger piston area calipers are OK with the long travel brakes, as it is easier to modulate on the track.
For me, I despise the longer travel, especially when my 17 Fusion Sport has about the same stock braking system as my stock 14 GT had, yet travel is extremely short and feel/pressure required is outstanding (again, for me). I'm only 150 lbs, so it also depends upon you overall body size/strength. If you squat 600 lbs, you probably naturally push harder on your brakes than I do.
So all that said, how to fix it. The S550 PP MC fits with some fab work, one new custom made brake line, and a custom made adjustable booster rod. You do lose the MC level sensor function (you can keep sensor connected to allow ABS and TC to still work), and it does fit with a TVS, but I never felt like I got the brakes fully bled when I had that setup, so I went back to stock) thinking either I did something wrong on the conversion or the parts just did not work well together.
One of the issues I had, but did not think about at that time, was I had put a much more aggressive pad on (not a track pad, but aggressive street) and the pads needed a bit to warm up, exasperating the issue of me thinking I had no/little braking. Anyway, I have a full write up on it as trackmustangsonline (search on OX1 on that board and it should come up).
The other thought I've had recently is maybe changing pedal ratio. It will make my pedal travel shorter, but at the expense of forcing you to press harder on pedal to get the same line pressure. I think I am OK with both of those.
I found this cool bracket setup that is used to swap to manual brakes. What I want to do is kind of the reverse, with less pedal ratio (the kit below is for more ratio, to convert to manual brakes). But I can build my own bracket, I just like the idea of being able to change pedal ratio without moving pedal pivot point or master cylinder location. So I might try this setup at some point if I get to it. I also like the fact I can put it back to stock if I don't like it. I will need to drill one new hole in brake pedal, not sure how hard it is to get an auto brake pedal assy out.
https://www.speedscience.co.nz/prod...olt-on-6-1-pedal-ratio?variant=39719182172259
There is also a rubber disk in between the booster diaphram/input rod and MC rod (output). I suspect Ford put it in for NVH, but no one has ever explained to me why it is there and why I should not replace it with something harder, maybe even Delrin to get some better pedal feel. It fits in the inner end of booster rod, see here. Many go to great lengths to stiffen MC and/or firewall to eliminate flex, yet Ford puts a "squishy" rubber disk in your stock braking system from the get go, go figure!! I have done a ton of modified/upgraded braking systems on old Ford trucks and Broncos with different boosters/MC's and even several different style hydro-boosts, and have never seen a rubber disk like this before.
