Want to upgrade my brakes on 66 fury

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Got a 66 fury, I put a duel pane master cylinder on it but my brake booster doesn’t seem to handle it very well. Was wondering if I could swap a full booster and master cylinder setup for 4 drums from a 67 fury. Does the pushrod fit or is there a different option for this.
 
Got a 66 fury, I put a duel pane master cylinder on it but my brake booster doesn’t seem to handle it very well. Was wondering if I could swap a full booster and master cylinder setup for 4 drums from a 67 fury. Does the pushrod fit or is there a different option for this.

That is a dual pot master cylinder. The '66 drum brakes have a midland booster same as '67 so a properly functioning booster should work fine with the new Master Cylinder. Some things to check. 1.) If your pedal is too far down before the brakes engage, there is a travel rod adjustment to adjust the height of the pedal before it engages. This is adjusted by removing the master cylinder. The rod sticking out of the booster has a nut on the end of it that can be screwed in or out to adjust the travel before the brakes engage. 2.) Are you sure the brakes have been properly bled. Air in the brake lines will cause a stiff pedal with erratic braking. 3.) You brake booster is now over 50 years old, it very likely may need to be rebuilt. Are you getting a sustained hiss from the booster with the engine running? If so the internal diaphragm is likely leaking. You should also replace the hose from the manifold to the booster as after this much time it is rotted and at the point of failure if it has not done so already. The internal liner of this hose sometimes detaches and blocks the flow of vacuum to the booster. If you noticed fluid residue on the front of your booster when you changed master cylinders, likely brake fluid has gotten inside the booster and that causes the rubber parts inside to fail. These booster are no longer stocked at most auto parts. Your best bet is to send it to www.boosterdeweyexchange.com or some other quality rebuilder and have it repaired. Avoid Cardone boosters as they are poor quality and they have an annoying habit of supplying the wrong booster.
If you do not already have a copy of the FSM, download one for free at www.mymopar.com, you will find the service manual in the Tools/Reference section from the home page.

Dave
 
I don’t hear any air coming out of the diaphragm and I changed the hose already coming to it as I suspected that I was losing vacuum through it. I bled the brakes and still have a very soft pedal and very strange braking. I will check the adjusting rod maybe I screwed up when putting it together. When I shut the car off I can feel the pedal push back on my foot almost like it’s getting a kick back in the system.
 
I don’t hear any air coming out of the diaphragm and I changed the hose already coming to it as I suspected that I was losing vacuum through it. I bled the brakes and still have a very soft pedal and very strange braking. I will check the adjusting rod maybe I screwed up when putting it together. When I shut the car off I can feel the pedal push back on my foot almost like it’s getting a kick back in the system.

That will be the pedal moving because the diaphragm has lost vacuum. Start the car, and then shut it off, you should retain vacuum long enough to apply the brakes with assist at least once. If the pedal goes dead immediately, the diaphragm is leaking and you need booster repair.

Dave
 
The brakes should act the same regardless of which master cylinder in attached to the booster. If the booster is malfunctioning, the engine will miss when you apply the brakes, plus possibly the hissing sound when the booster is operating.

FIRST, though, make sure the brakes are adjusted properly and the brakes start to apply near the top of the brake pedal's travel. NOT 1/2 way down as most GM's do. THEN, remove the drums and spray them down, the linings and the drum, with brake cleaner. This will remove the accumulated brake dust. Dispose of the collected dust properly, as it might have some asbestos in it. Reassemble to specs. THEN see how much positive difference that can make in how your brakes act. With the drums off, you might procure a "brake drum caliper" that will also match the brake lining adjustment to that drum diameter.

To me, do these things FIRST before you start seeking to adjust the booster's push rod (from the brake pedal) or the master cyl pushrod (between the booster and the master cyl). These things typically do NOT get out of adjustment with use, so once set at the factory, no need to mess with them as the car's age progresses.

Back when "the air was clean and sex was dirty", our service station guy recommended that we get the brakes "blown out" with ah air hose. Getting the accumulated brake dust out of the drums. It made a significant difference! But it dusted everything in the dealership's service department. So, that's why I mentioned getting the linings/drums cleaned up, in the more environemetally-friendly manner that we have to use now.

Just some thoughts,
CBODY67
 
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