So I'm hoping someone here will have some experience/suggestions on what to look at next. I initially overhauled the brakes by rebuilding the calipers, and adding a new set of hawk pads and a new set of rotors, plus a strano master cylinder brace. Found the front brakes dragging, so I bought a new/used set of calipers. Cleaned them up and greased everything, still dragging. Backed the strano brace all the way off - had very little preload to begin with. Still had problems on passenger front,but this made the biggest difference. Replaced caliper lines with stainless braided, still had problems. Was having an abs error so I continued chasing that down in case it was related. New abs computer, bleed abs block with the tech 2 abs bleed program, then the brakes. No dtcs anymore, abs restored. Still had dragging front passenger. Full rebuild the new set of calipers. Same thing.
I'm a bit lost now. The dragging front passenger is minimal, but still there. I can easily tell it's dragging when the car is in the air. There is no play in the pedal - the moment you begin to press on the brake pedal, they are starting to work. I can't understand why something would change unless it's always been this tight and the rubber caliper lines and old fluid gave it just enough play to not bind. I had far far too little preload to bend the firewall in any way, not that I'm clear as to whether that would cause a problem or not... But it does seem the bulk of the problem went away when I removed the brake brace. I'm to the point where I feel like I need to pull the passenger caliper again and check for bent pins, though that's just grasping at straws - everything is lubricated properly and pins packed with fresh brake grease, and moved freely off the car. No pulsing pedal either, so rotors are still straight. The fact that the pedal is so responsive right off the top of travel tells me something is afoot clearance wise, and i can't for the life of me think of what would've changed.

​​​​Thanks for any help or suggestions, I'm all ears

 

For me,removing the brake brace would've been a clue. With the brake pedal released, all system pressure (s) should drain/flow back to master cylinder. Could the brake booster be not allowing a full return.

 

I agree, the brake brace is a sign of something. I don't understand clearly enough how the booster plays into things, or works for that matter and I have a general idea of how the master cylinder works... Two ports, res port blocked off when pressure is called for in brake lines. The booster is pixie dust magic for me though. I'll get on Google and see if I can understand the mechanics, maybe there's something there