Paul!
I was wondering if you were going to chime in. I'm impressed, if not a little disturbed, that you remembered my purchase date.
To be fair, it's a *really* expensive exhaust pipe that has me concerned-- and I'd rather not remake it. Seriously, 321 stainless mandrel bends, CNC'd stainless manifold & turbo flanges, and wastegate V-band flanges aren't cheap... plus my frustration involved with fitting and welding it up.
Everything you said makes perfect sense. Unfortunately for me turbos and all the extra plumbing really make things tight. I knew that going in, and I'm certainly feeling the pain now. With a heat shield and a little high temp insulation the master cylinder as it sits now will probably survive just fine even though the very nose of it is rather close to the wastegate. I'm also pretty sure there's room for the PSC remote power steering reservoir and the Lee filter. Actually, I see PSC now makes a much nicer hydroboost-compatible reservoir with a built in filter compared to the one I purchased from them about 4 years ago... that would make things easier.
Another option is to get one of your super-shorty masters to pick up about 3" of additional clearance and keep my current brake setup... and that is something I've thought about as well. It would save a ton of money being able to keep the current hydroboost and calipers which I know work well together.
The main reason I'm looking at a complete re-do of the brakes is I'm going to be changing to a 9" floater rear end... and that means new rear brakes. Seems the common setup with floater rears is Wilwood 4 piston radial mount calipers like the Aero 4 or FNSL4R and even with the smallest piston sizes they offer they will be *way* out of proportion to the front C6 PBR calipers in terms of piston area which is going to majorly screw up the front to rear balance of the system. Then again, maybe I can fab my own caliper brackets to use my current PBR rear calipers on the new floater-- but it's hard to say without having all the parts in front of me to take measurements. Besides, if I'm going through all that effort to switch to the new 9" floater I'm not sure I want to continue using the C4 PBR e-brake calipers; the e-brake is OK at best and the pads are so small the pad life is really short. When the car was still running and driving I recall the rear pad life was maybe 1/2 the mileage of the front pads.
Another option I'm considering is one of the Wilwood configurations I laid out in my first post but paired with the Hydroboost and a 1.125" tandem master... but I'm worried such a setup might be *too* touchy. The Wilwoods have a lot of piston area and thus don't need a great deal of line pressure to generate lots of clamping pressure-- and while the 1.125" master will increase the pedal effort I know the Hydroboost will have zero problems generating a *lot* of line pressure even with the 1.125" master. I suppose I could drop the piston sizes on the front calipers to 1.625/1.125/1.125 and use the 1.125/1.125 piston rear calipers with the hydroboost setup and 1.125" master cylinder to increase the pedal effort and decrease the "touchiness" of the pedal... maybe that's the path forward. Thoughts?
Paul, maybe you can help with some numbers, since my car is in pieces and I never put a pressure gauge on my calipers when it was together... what kind of brake pressures can you see out of a hydroboost and 1.125" master combo? With the Wilwood setups I have in mind it looks like 550-750psi (depending on caliper piston size) is going to provide "eat your steering wheel" brake torque on the order of 4000 with street friendly pads and a ~0.43 CoF. That's why I'm concerned things may be too touchy.
Just trying to look at the "big picture" and lay out a plan before changing or purchasing any parts. One little change leads to another-- in this case the new floater rear end is probably going to require changes to my entire brake system because of the need for new brakes for the rear end. Nothing has been decided as of yet but there are a lot of potential configurations to consider.