Golden Goddess heart surgery

[Chongo 68]

SWEET!

 

[Cheapsunglasses]

I might have come up with what could be an issue. The car was originally manual drums, I put the pirate jack front disc and booster on. I don’t think the pedal is coming up enough, I’m wondering if this part is adjustable, or do I need to get an adjustable push rod

 

[Kern Dog]

Here you go.....

Members with 4 wheel disc systems.....Can you get the tires to skid?

Look at post # 159 and later.

 

[Cheapsunglasses]

Here you go.....

Members with 4 wheel disc systems.....Can you get the tires to skid?

Look at post # 159 and later.

Sorry I guess I didn’t read that far lol. That’s what I was thinking I needed to do. So that part is hallow, or I have to drill and tap it?

 

[Kern Dog]

The part is solid. A friend modified it for me.
My original plan was to cut it in the middle and weld a small piece in between the two halves.

 

[Cheapsunglasses]

I don’t have a welder, I don’t have a drill press or a lathe, or anything with any kind of precision. But I do have a few hardware stores in the area, and 1 had what I can make work

 

[Kern Dog]

That could work. For me, the hole needs to be barely bigger than the bolt going through it so the stuff doesn't rattle. Some thin sleeve may be necessary.
The one made for me allowed me to extend mine approximately 3/8" to 7/16". I ended up extending it about 5/16". For me, it is close enough to leave it.

 

[Cheapsunglasses]

I just need to figure out why I have a good, firm pedal, but almost no braking and a lot of fade

 

[ckessel]

Try some new frictions maybe? One of the problems Greg found on his journey.

 

[Cheapsunglasses]

Yeah I’ve been talking to him, he’s given me some great information.

Maybe different pads, maybe smaller bore master cylinder, maybe even braided steel lines instead of rubber are my current theories

 

[Cheapsunglasses]

I might have brain stormed another thing. The rod from the booster to the master cylinder is adjustable, and I've made an adjustment before, but I'm now wondering if it was enough

 

[Kern Dog]

The length of the linkage rods will not make a difference in pedal feel. If the feel is that of a hard pedal that gives inadequate brake force, the problem lies elsewhere. Mine was an inadequate booster volume for the 4 wheel disc caliper requirements. The big calipers require more pressure to function compared to drums or a disc/drum system.

 

[Cheapsunglasses]

I’m talking about the rod that pushes the master cylinder in on the booster, I’m now wondering if that rod is long enough. This little guy

 

[Kern Dog]

That will affect pedal height.
Pedal feel, hardness like you're dealing with is another matter.
My experience has shown me that a hard pedal with poor braking is a matter of not having enough leverage.
You can have poor pedal leverage and the force your foot makes is not leveraged/amplified enough to generate adequate force to the calipers or drums.
The booster systems have less leverage than a manual brake system but the booster amplifies the amount of pressure your foot gives the pedal.
With my setup, I tried numerous master cylinders when I tried to run manual brakes. I drilled a hole higher up on the pedal to increase the leverage. It still wasn't enough. For me, I needed additional boost to reduce the pedal effort to comfortably stop the car. If I had Hercules legs, the manual setup may have been fine if it didn't bend the linkage doing so.
Even with the first version of power brakes, it wasn't optimal since I was using an A body single diaphragm disc/drum unit. That worked fine when I had rear drums but the additional volume needed when I switched to the rear discs made the old booster inadequate.
In short, it sounds like you need to look at the booster. In the two examples I have experience with recently, both of these cars:

Have stock reproduction 1966-70 B body disc/drum dual diaphragm boosters, stock linkage parts and the pedal feel is excellent with both.

The red car does have the adjustable pushrod:

The pushrod did not affect the pedal feel, it was merely cosmetic.....to make the brake pedal rest at the same height as the clutch pedal.

 

[Cheapsunglasses]

Ooooooooh, I had no idea it did that, I thought is was for more pushing, thank you for your patience and explaining it.

So do I start experimenting with master cylinders and see what that does, if so what should I be looking at?

 

[Kern Dog]

The booster just acts like a "helper" that reduces the effort to push the pedal. Because it takes what effort your foot makes and in a way, "amplifies" it.
The factory disc/drum arrangement used a master cylinder with a 1 1/32" bore, if I recall. I'm not real sharp on the how or why of hydraulic pressure versus volume but it is a common belief that a smaller bore master cylinder produces more pressure but with less volume. It means a longer pedal stroke but greater pressure. I equate this to a garden hose with no nozzle....the flow is greater but doesn't go as far as when you put your thumb over the end and cover most of the flow. It now sprays much further but with less water doing it.

 

[Cheapsunglasses]

I know what the booster and master cylinder’s do, it’s the sizing and levers and pedals that have me confused if that makes sense


The master cylinder that came with it is a 1.125” bore.

Oh, I just reread what you wrote for the 4th time and realized you were talking about boosters I need to experiment with.

Is there any kind of formula or anything to determine booster or master cylinder size?

 

[Cheapsunglasses]

I was digging through my parts piles and I found this. I believe this came with the disc brake conversion kit. I have no idea why I didn’t use it, and why I left the drum/drum one on, but since it’s laying around I want to put it on first and see if that’s an issue. The question is, which lines go where?

 

[Kern Dog]

Some call this the "Texas" valve.

The lines connect similar to the distribution block as shown below.

Here are the sizes.

 

[MarPar]

Some call this the "Texas" valve.

View attachment 1527708

The lines connect similar to the distribution block as shown below.

View attachment 1527709



Here are the sizes.

View attachment 1527710