63 brake booster questions

-

63Tigerlily

Well-Known Member
Joined
Feb 15, 2022
Messages
75
Reaction score
72
Location
SoCal
I read a bunch of threads on here about power brakes, but couldn’t quite find the answer.
I recently put a 76 scamp disc setup on the front of my 63 Dart. I got the valving from DoctorDif and the master is a stock disc/drum 76 scamp master.
I decided to use a factory 63 single chamber power booster. I robbed it from a crashed 63 ragtop. When I put it in, my pedal dropped about halfway to the floor before resting. Lots of freeplay! I don’t have the ragtop anymore so I can’t verify if it had a different pedal than the manual brake models. The booster pushrod isn’t adjustable. After the freeplay, I can feel braking. There’s also a sticky spot in the middle of the freeplay.
I’m thinking about making an adjustable pushrod and putting bushings into the sloppy holes that hold the links in the standoff bracket.

Any specific knowledge on these 63 boosters?
 
for this application you may need two adjustable push rods. the one in the booster that engages the master should be adjustable as well as the one under dash that goes from the bracket to the pedal. when you're mixing and matching brake parts, you really want all of the adjustment you can get so that you can dial in the system as best as possible. and even then, there's mismatches in the parts and stuff just doesn't wind up working right.

oh, and the pedals are the same. there's no difference between power and manual.
 
Let's see a picture of the booster in question.
Could be a Bendix,
1749172377588.png

Midland,
1749172410385.png

or Master-Vac.
1749172440463.png

But I'm going to take a wild stab in the dark here, and say that you didn't grab and install the separate vacuum reservoir tank and check valve that these early boosters need in order to work...
1749172828858.png

1749174123042.png
 
Last edited:
That’s gonna be it. It wasn’t on the ragtop, so it must’ve been harvested by someone before me.

IMG_1764.jpeg
 
Let's see a picture of the booster in question.
Could be a Bendix,
View attachment 1716414668
Midland,
View attachment 1716414670
or Master-Vac.
View attachment 1716414671
But I'm going to take a wild stab in the dark here, and say that you didn't grab and install the separate vacuum reservoir tank and check valve that these early boosters need in order to work...
View attachment 1716414676
View attachment 1716414690
I was scouring the net for a diagram of the booster and only found the bendix.
Let's see a picture of the booster in question.
Could be a Bendix,
View attachment 1716414668
Midland,
View attachment 1716414670
or Master-Vac.
View attachment 1716414671
But I'm going to take a wild stab in the dark here, and say that you didn't grab and install the separate vacuum reservoir tank and check valve that these early boosters need in order to work...
View attachment 1716414676
View attachment 1716414690
I was searching the web for a diagram but only found the bendix style. This setup is similar to my 56 Imperial so I think I can conjure up a fix and try it.

I know the guy that owned the rag and he drove it daily, but as I think on it, he’s a custom car painter and it is quite likely he drove it with the brakes like that and may be why he crashed it in the first place
 
I was scouring the net for a diagram of the booster and only found the bendix.

I was searching the web for a diagram but only found the bendix style. This setup is similar to my 56 Imperial so I think I can conjure up a fix and try it.

I know the guy that owned the rag and he drove it daily, but as I think on it, he’s a custom car painter and it is quite likely he drove it with the brakes like that and may be why he crashed it in the first place
Go to Home - Harmon Classic Brakes
They list all three boosters, as well as parts and rebuilding service.
I don't think they're listed, but I would contact them about the reservoir and correct check valve- who knows, they may have something sitting on a back shelf. Or try a "Parts Wanted" ad on this site; it's free.
Honestly, by the time you source the rest of the parts and get it put together, you could find out the booster needs rebuilding... why not just get and install Dr. Diff's booster and brackets? All brand-new, and no reservoir required.
 
Last edited:
If anyone has a page from the manual they can post, it would be easy.
 

Go to Home - Harmon Classic Brakes
They list all three boosters, as well as parts and rebuilding service.
I don't think they're listed, but I would contact them about the reservoir and correct check valve- who knows, they may have something sitting on a back shelf. Or try a "Parts Wanted" ad on this site; it's free.
Honestly, by the time you source the rest of the parts and get it put together, you could find out the booster needs rebuilding... why not just get and install Dr. Diff's booster and brackets? All brand-new, and no reservoir required.
I did reach out to dr dif on it and that may be the route I’ll go.
The conjuring would only be because it’s there now, and maybe I can make it work with some spare stuff. But…. Maybe I’ll just swap it
 
Go to Home - Harmon Classic Brakes
They list all three boosters, as well as parts and rebuilding service.
I don't think they're listed, but I would contact them about the reservoir and correct check valve- who knows, they may have something sitting on a back shelf. Or try a "Parts Wanted" ad on this site; it's free.
Honestly, by the time you source the rest of the parts and get it put together, you could find out the booster needs rebuilding... why not just get and install Dr. Diff's booster and brackets? All brand-new, and no reservoir required.
Oh. Also because the single chamber is a bit more demure in the engine bay and I like the way it looks. But I like stopping even more
 
Disc brakes require about 50% more line pressure than drum brakes & the booster you have is off a drum brake car. Disc brake cars usually have a bigger booster. You are better off getting a booster off a later model car that had disc brakes. Also, drum brake cars used a Residual Line Pressure Valve which will not work with disc brakes, will bind them up. Usually located in the outlet port.
 
Disc brakes require about 50% more line pressure than drum brakes & the booster you have is off a drum brake car. Disc brake cars usually have a bigger booster. You are better off getting a booster off a later model car that had disc brakes. Also, drum brake cars used a Residual Line Pressure Valve which will not work with disc brakes, will bind them up. Usually located in the outlet port.
My valving is from doctor dif. We went over my whole setup and I bought his his recommendation.
Originally I was gonna do manual brakes until I realized I didn’t have a pedal pushrod. That’s when I threw the booster in.
All just fun hotrod stuff. I’ll probably get just get the new setup and be done with it. The engine bay isn’t for show anyway
 
huck the booster and get the adjustable manual rod like @Professor Fate linked to.

you *may* have to ream/open up the hole in the pedal arm slightly, but other than that, it's straightforward.
 
I didn’t have an adjustable pushrod at 11pm on a Tuesday night. The car is my wife’s who works at the high school and they had a little car show on Wednesday.

On sunday it had no front or rear suspension in it. I was tired. I three the booster in in lieu of no rod.

I think she might enjoy the power assist, though.
 
With the brakes not coming out great, I drove it down to the school for her.
 
-
Back
Top Bottom