[csouther]

I have a 1965 mustang that I have recently converted to 4 wheel disc brakes with a power booster and modern style master cylinder. My problem is that my pedal goes straight to the floor and needs to be pumped 3-4 times before getting any real bite on the brakes. Even when it does start to bit its not enough to lock them up. Here's the setup.

- 1994 cobra MC (modded to fit on small diameter vacuum power booster)

Front:
- Fed from rear port of MC
- Wilwood 2 lb residual pressure valve before a T fitting that goes to the front brakes.
- All flex lines are braided stainless
- sn95 dual piston calipers on Grenada spindles and rotors

Rear:
- Willwood prop. valve right off of the front MC port for the back brakes.
- Wilwood 2 lb residual pressure valve before a T fitting that goes to the rear brakes.
- Rear discs are a jegs 9" disc kit that uses those GM metric single piston calipers


Things I have checked:

- Checked vacuum booster rod engagement to the MC
- Bled, bled, bled


Is there something about the 95 cobra MC that I don't know? I'm not using the the distribution block but though that using the res. pressure valves would correct that. Could my MC be bad? It's brand spankin new but I did get it from autozone so you never know. Is there a way to check is it bad and is leaking internally or something? I need a brake expert here that has played with mismatched mods. Thanks ahead of time.

Here's a post that I was able to get some pictures up.
http://www.allfordmustangs.com/forum...ml#post2867522

[67svtstang]

1. Did you bench bleed the master cylinder before installing it?

2. How are you bleeding the brakes?

[Blue67coupe]

^+ Bench bleed it. Sounds like there is still air in the lines. I use to have the same problem. Replaced my Master cylinder and bench bled then each individual wheel and it stopped the pedal pumping.