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Discussion Starter #1
65 Convertible disc/drum setup ,just had new dual reservoir m/c and booster installed , new rotors and calipers and lines ,new wheel cylinders and shoes on the back.
Struggling with long peddle travel and soft stopping. Have bled several times and adjusted the rear brakes as much as my mechanic is comfortable with. It's better now but I'm still not thrilled with the stopping ability. I don't think its air in the lines because I can't pump the peddle up. I been following a couple of recent threads with great interest.
Should I be able to "lock" these brakes up ? right now that's not possible.
Wondering if I just need to get my head around the fact that it's an old car or is there a problem?
 

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Dimples
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What are the details on the addition of the booster? What swap did you go with? Was the pin relocated on the pedal? This is an important step to adding a booster.
 

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Discussion Starter #4
not sure which kit my mechanic used and I thought he told me 65-66 did not have an adjustable pin on the peddle ?
Mechanic has the car now so I cant take any pics
 

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Dimples
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not sure which kit my mechanic used and I thought he told me 65-66 did not have an adjustable pin on the peddle ?
Mechanic has the car now so I cant take any pics
Not an adjustable rod, a relocated pin. The place where the rod mounts needs to be moved on the pedal arm itself. Find out what swap your mechanic used.
 

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Discussion Starter #6
ok, I'll find out. He gets most of his parts from NPD but I 'm not certain where this kit came from.
 

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Sounds like you need a new mechanic.
He/she shouldn't be releasing work that isn't RIGHT. (and leaving you to figure it out)

ex-Global West GM
1991-1995
 

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I’m following this thread closely. My brakes do the same thing. I’m curious on the relocating the pin you speak of. Can you please explain that to me.
 

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Dimples
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Power brakes (both factory and swap kits) move the location of the pin that the actuator rod mounts to on the pedal. So if you’re putting a booster on a car that came with manual brakes, this pin needs to be relocated.

I’m no engineer, so I can’t tell you all the why’s and wherefore’s, but it is necessary on all swap kits that I’ve ever seen. Perhaps there are exceptions, but not in my experience.
 

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Discussion Starter #11
Just to add a little more info. When I bought the car it had Non Power front disc with the large bowl single reservoir.
The brakes were not functioning when I purchased the car and had been sitting for 5 years.
As much as the peddle travel concerns me , I'm more concerned about the lack of stopping power and not being able to "lock up" the brakes.
 

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Dimples
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Do you drill another hole and put the pin in that? Sorry to sound stupid, just trying to learn.
Basically, yes. Or you put in a new pin.

Just to add a little more info. When I bought the car it had Non Power front disc with the large bowl single reservoir.
The brakes were not functioning when I purchased the car and had been sitting for 5 years.
As much as the peddle travel concerns me , I'm more concerned about the lack of stopping power and not being able to "lock up" the brakes.
Pedal travel can be part of that equation, though you may have other issues as well.

This is what I have, so you can see what I'm talking about.

 

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Discussion Starter #14
I just think there must be a physical problem if I can't lock the wheels up during a hard stop
Where the residual valve that I have read about located ? can you tell just by looking if I have one ?
 

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Dimples
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I just think there must be a physical problem if I can't lock the wheels up during a hard stop
I think you’re right.

Residual valve can be a separate part located somewhere on the rear line or built into the master.

I don’t know this for sure, but seeing as the residual valve is there to maintain a small amount of pressure to preload the brake shoes so that there is less delay between pedal and actual braking, I don’t think it would significantly impact overall braking power. Rather, it takes less pedal to begin actuation.

Would love to know if I’m wrong though if any hydraulics experts know better.

I do like the idea of checking the adjusters in the rear.
 

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I think you’re right.



Residual valve can be a separate part located somewhere on the rear line or built into the master.

I don’t know this for sure, but seeing as the residual valve is there to maintain a small amount of pressure to preload the brake shoes so that there is less delay between pedal and actual braking, I don’t think it would significantly impact overall braking power. Rather, it takes less pedal to begin actuation.

Would love to know if I’m wrong though if any hydraulics experts know better.

I do like the idea of checking the adjusters in the rear.
Exactly as you stated. The residual will keep the line charged with pressure. Then it take less pedal/master movement to achieve the results on the rear brakes.
Vast majority of pedal travel is residual, improper adjusting, plumbed wrong.
Hydraulic is just that, not a complicated issue.
 

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I had the exact same problem, then finally figured out I did not change the pin as already mentioned. It obviously puts the wrong angle on the rod into the master cylinder, hard to figure but it solved my problem.
 

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My kit from NPD came with an adapter to relocate the push rod. Below is a pic of my kit and the adapter is on the right.

759766
 

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The '65/'66 cars did not have different pedals for manual and power brakes. For power brake cars there was an adapter that went between the firewall and the booster that changed the ratio of the pedal for power brakes. You can see it in the photos of this kit.
 

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Discussion Starter #20
OK , so I think I need that adapter for the peddle travel issue
BUT even with the longer peddle travel I should be able to lock the brakes up...
 
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