Topic: 67 Shelby 10x2 1/2 Rear Brakes

[Bossbill]

Charles showed his excellent rear brake restoration.  I wondered what the
wide rear drums on my 67 Shelby should look like.
http://www.concoursmustang.com/forum/index.php?topic=1696.msg8676#msg8676

I took the 67 Shop Manual brake pic and colorized the pic with a notation of the brake parts I found or did a best guess as to what the colors were based upon their degraded state.

I do know my brakes are not original as the cylinders do not have the small bleeders.

Is there a hardware kit that would be a good start?

Edit to correct typo in subject...

[J_Speegle]

Just as a quick response for one of the finishes I've seen a fair number of  the self adjuster arms/levers in zinc dichromate

Someone else went through and listed the finishes of items using the same drawing and posted it a while back on one of the forums (sorry don't recall nor did I label it by source) but that was done for 64-66 So won't report it here.

[Bossbill]

I agree on the Adjusting lever. I cleaned mine up better and see a bit of gold color on the back.

I do understand the years are different, but the 67 brakes appear to have more features in common with 65/66 than later years. Note the absence of the fat T washer at the pivot location in the Boss picture vs. the 66.

I did find another 66 K code picture that Charles posted:
http://www.concoursmustang.com/forum/index.php?topic=13659.0

I see he has mentioned the turquoise hold down spring on the Primary shoe and the black on the Secondary. I thought all of the paint on one of my hold downs was all gone, but it could well just be black. I also have the turquoise hold down spring.



Bob Gaines did reply to a post regarding rear brakes which listed some finishes:
http://www.concoursmustang.com/forum/index.php?topic=3197.msg17192#msg17192

Here is an update to my first annotated image. I left the brake shoe metal as Brown since I have no data for 67.

On edit -- After another few hours of searching and cleaning I think I can safely say the "Parking Brake Cable Housing Retaining Grommet" is yellow, like in Charles' pic.  I'll update my pic master and wait for some data on brake shoe (metal) color (hint, hint).

[Bossbill]

Through my Eastern ally I got word that the 67 shoe finish was metallic, just like Charles' shoes.

Unless I get some corrections here is the final.

[Bossbill]

At one time I thought that the metal portion of the rear brake shoes could also be rusty red -- like the pressure plate color.
But then I spotted these 10x2 1/2 C6OE-As and see they are silver. Just like the pics of the early car's shoes above. And as verified by my Eastern ally.

Is the C6OE-A the correct shoe or did Shelby specify the C3OE-D "fade resistant" or maybe something else? I didn't think the 67s used the segmented semi-metallics.

[Maybe I should add the pic?]

[Bob Gaines]

At one time I thought that the metal portion of the rear brake shoes could also be rusty red -- like the pressure plate color.
But then I spotted these 10x2 1/2 C6OE-As and see they are silver. Just like the pics of the early car's shoes above. And as verified by my Eastern ally.

Is the C6OE-A the correct shoe or did Shelby specify the C3OE-D "fade resistant" or maybe something else? I didn't think the 67s used the segmented semi-metallics.

[Maybe I should add the pic?]

67 Shelby's did not use the segmented semi-metallics.

[Bossbill]

There is almost no data on the Shelby rear axle since the whole assembly was listed as part of the add/delete SVO sheets. Other than tribal knowledge, of course.

Since my rear brake cylinders were replacements I looked for either an MPC list of what it had originally or any other document on the cylinder size. Found nothing specific, just inferences. I then looked for the most likely candidate which is the 'B' station wagon with 10x2 1/2 brakes. That matched the Blue dot C3OZ-A.

JD showed a listing on his for sale site (http://www.allclassicmustang.com/1967MustangPartsNew.html) where he had a pair of 65/67 Shelby rear cylinders noted as having Blue paints dots. This decodes as follows:

Drum Dia...........Engine..........Cyl Dia....Color.........Part No.
10x1 3/4...........289 4V-GT......7/8........Green........C6OZ 2261/62-A   
10x1 3/4...........390 4V...........13/16.....White........C7ZZ 2261/62-A.....CB Brown
10x2 1/2...........Sta Wgn.........15/16.....Blue*........C3OZ 2261/62-A   

*Blue is also noted as a 6 cyl cylinder of size 27/32.

So while CB Browns reproduction is identical in appearance, it's the wrong cylinder size for a Shelby. I suppose I could either let it be or bore them out and put in differnt pistons.

Is there any other data on this?

[Bossbill]

Thought I'd post anew with other data.

I did look on the SAAC Forum and confusion reigns.
http://www.saacforum.com/index.php?topic=1086.0
The original poster said 7/8. That's the replacement that I have. I think it wrong.
CBrown says C7ZZ which is what he sells but he had a question mark at the end.
One other user said his were 15/16. He posts here.

The exact repos on NPD do not state Shelby but are the 390GT versions. I think those are CBrown's.

[Bob Gaines]

Thought I'd post anew with other data.

I did look on the SAAC Forum and confusion reigns.
http://www.saacforum.com/index.php?topic=1086.0
The original poster said 7/8. That's the replacement that I have. I think it wrong.
CBrown says C7ZZ which is what he sells but he had a question mark at the end.
One other user said his were 15/16. He posts here.

The exact repos on NPD do not state Shelby but are the 390GT versions. I think those are CBrown's.

It stands to reason that the wheel cylinders would be the same as the 65 or 66 GT350 backing plates with 2 1/2 brakes. 29/32 in those cases. I think 15/16 is close.

[Bossbill]

If you increase the lining area without increasing the hydraulic pressure ( larger piston in the cylinder) you can increase fade resistance but you don't increase stopping power.
The Cobra Automotive guys start at 1" and go as high as a 1 1/8" on their competition cylinders.

Since my extreme usage might be to keep the car from gaining too much speed down the trailer ramp I'll be safe with most any size.

Blue dots it is. Thanks Bob.

[Bossbill]

While trying to source parts to have a complete and correct rear brake system, I dug a bit deeper and found someone who actually had a complete factory breakdown of the 65/66 Shelby rear brakes. Every part was listed with either a FoMoCo, Shelby or K/H part number.

What I found was very interesting.
First, although a number of people assume the rear brakes were based on the Galaxie or T-Bird rear brakes, both of those are 11x2 1/2 systems from 1960-on. The Shelby system is a 10x2 1/2. As I drilled into all of the FoMoCo parts used it became apparent that the baseline was the 63 (up) Fairlane Station Wagon (S/W) -- also a 10x2 1/2.

What was changed from the S/W were the high temp shoes, replacement of all of the springs with K/H high temp springs (due to metallic shoes) and 29/32 white dot cylinders (used on non-S/W applications).

What's that got to do with the 67 Shelby brakes?
As it turns out all of the 65/66 Shelby features for high temperature were removed and the unit reverted back to a stock S/W configuration. No more segmented brake shoes which required the high temp springs.
 
Please note that I don't have a 67 Shelby breakdown. My conclusion is based on the new for 67 Shelby cylinder size and the Fairlane standard brake brake shoes used. In other words, a very stock Ford configuration without the high temperature Shelby mods.

Finding data on each part of the 67 system involves a deep dive into the 60-68 MPC for each of the 30 parts in the brake system for the S/W.

Rather than list each part I'll summarize.
Standard spec:
- S/W 10x2 1/2 drums
- S/W rear shoes (bonded).
- All springs are stock S/W
- Wheel cylinder is now the S/W blue dot 15/16"

[Bob Gaines]

FYI the wheel cylinder castings are the same external appearance with no identification of the different interior sizes .One casting used just bored to different sizes . 

[Bossbill]

Yes, it appears there is no external marking.

Here is a pic of what is purported to be a correct set of brakes for a Shelby.
The cylinder is aftermarket, the green spring I have issues (more on this below) and with so much degraded the rest is difficult to say. Zinc dichromate on the hold down cups degrades very quickly.

On the spring front, the green spring is a double diameter. It's large at the shoe end for the first 4 coils and then gets smaller. All pictures I've seen of this era has a single diameter spring. Even the workshop manual shows both retracting springs as single diameter.
Notice too that this spring forces the parking brake link to angle down. It also rubs against the red spreader spring. Ford would not have allowed either situation.

I thought the double diameter was a later aftermarket replacement.
[yes, the one pic shows a front brake. The springs are the same.]

[Bossbill]

And then this supposed NOS double diameter green C2OZ-2035-C spring shows up on eBay.

https://www.ebay.com/itm/254993998509?epid=3013654406&hash=item3b5ed3a2ad:g:M8EAAOSw6cJgrpC-#viTabs_0