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Need help with a brake problem on a 65

Triton

Member
I have a long stroke of my brake pedal then it gets firm as it gets to the floor. The car doesn’t stop well. Here’s what I have and have checked!
1970 front disk brakes
Versailles rear-end
New 1994 master cylinder 1 inch bore
New 1990 brake booster
Adjustable proportioning valve
Stainless steel brake lines
Stainless steel brake hoses

The front calipers are rebuilt and mounted on the correct side with the bleeders on the top
Rear caliper are rebuilt and labeled left and right, also adjusted properly and emergency brake holds the car.
I have bled the brake several times and no air, brakes don’t feel spongy
I blocked off both ports on master cylinder with plugs and the pedal feels perfect and doesn’t leak down
The rear brakes are connected to the rear smaller port on the master cylinder
There doesn’t appear to be a brake pedal adjustment on the booster
My brake pedal ratio is 4 to 1
I can’t find any leaks in the system
I have been working on this for 3 months now and can’t figure it out!
My brake are fashioned like the setup here: http://www.ultrastang.com/info12.php
 
With the engine off, pump the brake pedal and see if it holds pressure. If it starts to bleed down, then there's a leak in the booster.

I think this is the correct test for a bad brake booster.
 
How much engine vaccum do you have?

Power brake booster test:
1.) Check engine vacuum you should have 14"-18" of vacuum at 625-800 RPM, 18"-21" vacuum at 1000 RPM.
2.) Vacuum checks good, start car and run engine up to 1000-3000 RPM for 30 seconds.
3.) Cut off the engine and then press the brake pedal 3 times. It should get harder to press and travel less each time you press it. If it doesn't, then the brake booster is suspect.
 
On the Main forum index, this title is shortened for the last post and reads "Need help with a bra". I can't help you putting a bra on, but I do have a number of tips taking one off... :yah
 
If you get a bad master cylinder from SSBC with your $1200 front disc brake kit, you'll never get them to bleed properly. In my case, SSBC had me running around in circles until I insisted they overnight me a new master cylinder. With this kit, they ship a crappy master cylinder (made in china). My right front caliper oozed black particles while bleeding the brakes from a slopshop powder coating job that got coating inside the caliper. And they acted like they were doing me a favor. SSBC's poor quality control and poor customer service Really wasted my time. Nest time, I'm going to look at Baer or Wilwood.
 
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