[Dragncar]

OK, basic stuff here. 69 A body brake master cylinder rebuild. Drum-drum. power assist.
Do I have a 1" bore or 1.25" bore. Think its the latter but have not disassembled yet.
I kind of want to rebuild it out of spite. Kits used to be dirt cheap, under 5$ Now you can not find them and they are 30$ if you can.
Its for my strip car so if I can not get it done cheap I will go all the way with Wilwood stuff.
Right now its semi marginal for braking, 12" booster running high 10s. New engine will have over 100 more horsepower, So far it seems to be true, could not hook it up and un prepped track in mild testing.
So I just want to rebuild my stock master cylinder and go from there. If it works OK, fine.
And it should be good enough to power one of these Wilwood front disc brake kits made for drum conversions
https://www.wilwood.com/BrakeKits/Br...+Brake+Spindle.

This rebuild kit might do the job. But does not say if its 1" or 1.25".
https://www.partsgeek.com/dh2frf9-po...19051118008005
Like i said, I kinda want to rebuild it out of spite.
Thanks for any help brake guys.

[OG68]

1" bore with the drum brakes. 1 1/8" with discs.
I've seen two drum brake rebuild kits on ebay over the last year. Both were over $85.

The kit you mentioned above is for a Bendix MC used on the B bodies. Not the same as the Delco unit for the A bodies

[Dragncar]

Originally Posted by OG68

1" bore with the drum brakes. 1 1/8" with discs.
I've seen two drum brake rebuild kits on ebay over the last year. Both were over $85.

The kit you mentioned above is for a Bendix MC used on the B bodies. Not the same as the Delco unit for the A bodies

So they used 1" cylinders were used on drums ever with power assist ?
My master cylinder has bleeders right above both brake lines.
None of the cheap rebuilt units I have seen online have those.

[65 Lamnas]

It may not be the cheapest way to go, but if you like your MC (convenient bleeder screws, etc) and it works well as part of your brake system, I'd have that master cylinder SS sleeved and get a kit from the rebuilder.....there used to be a place FOR YEARS that had a monthly ad in Hemmings called "White Post Restorations", they were out of NY, I think....start there if you want....?? Good luck.

[dataway]

Yep, basically new kits for 68/69 A bodies with power drum aren't being made anymore. I ended up finding one on ebay a couple years ago.

I also wanted to keep the original MC with the bleeders.

I keep a ebay search for the part number going all the time, almost never come up, when they do they close to $100 for a 40 year old, often dried out looking kit, sometimes missing parts.

[Dragncar]

Originally Posted by 65 Lamnas

It may not be the cheapest way to go, but if you like your MC (convenient bleeder screws, etc) and it works well as part of your brake system, I'd have that master cylinder SS sleeved and get a kit from the rebuilder.....there used to be a place FOR YEARS that had a monthly ad in Hemmings called "White Post Restorations", they were out of NY, I think....start there if you want....?? Good luck.

Thanks, but not THAT attached to that thing. I would buy whatever Wilwood recommends before I went to that trouble.
It is nice that there are companies that do that sort of thing though. I can imagine finding pre war brake parts difficult.
I was helping a old boss restore a military 6x6 truck from WWII. It had a Continental flat head 6 in it. The carb was this cast iron one barrel that they started making in the teens-20s. Finding floats, needles and seats and gaskets was a nightmare.
I ended up making him a adapter to run a carb from a Clark airport tractor he had with the same Continental engine. We got it running and made a parade.
Gas tank was so full of holes a had enough hours silver soldering them and coating the inside he could have had a new one custom made.
A open cab Dodge 6x6 is pretty cool !

[Dragncar]

Originally Posted by dataway

Yep, basically new kits for 68/69 A bodies with power drum aren't being made anymore. I ended up finding one on ebay a couple years ago.

I also wanted to keep the original MC with the bleeders.

I keep a ebay search for the part number going all the time, almost never come up, when they do they close to $100 for a 40 year old, often dried out looking kit, sometimes missing parts.

Yeah, they do not want us rebuilding our stuff anymore. Thing is, they are making the parts, just not selling them to us. I can buy this one for 36$ that looks the same with a different top cover and no bleed screws. But its made in CHYNA.
https://www.amazon.com/Dorman-M71277...69+Pontiac+GTO

And thay have this one Amazon says fits for 57$, looks different but made in AMERICA ( I think?)
https://www.amazon.com/Centric-Parts...69+Pontiac+GTO
Out of spite I am buying the first one and if my original bore is not pitted, swap the seals.
Sad they can sell us a whole unit for 36$ but won't sell us the seals for 15$, They would make more profit selling the seals.
Its almost like you have to fight being a do it yourself guy these days.

[rolling money pits]

I’m willing to bet that “made in USA” involves someone snapping the bail over the cap and calling it a day.

First Brands owns centric, and fram, raybestos, and a few others. Pretty sure I’ve read on here Fram is now being made in some Asian country, I cannot imagine centric being any different.

[Dragncar]

So, what is involved in switching a factory power brake car to manual brakes ?
Looking at Wilwood stuff they make front disc brake kits that work with power or manual brakes.
It would be lighter and cleaner just getting rid of the booster and the disc upgrade should get me enough braking without the booster. My rear drums are oversized from a 59 Ford pickup.
I do have a manual brake donor 69 A body.
Wilwood makes a MC kit to tun it to manual brakes, 388$ Its a 15/16 MC.
Can we get a 15/16" stock type MC ?

[Scarebird]

Try your 69 master - we did this with a 68 Firebird and it worked superb - depends on piston size with the Wilwood calipers.

Baer looks to have a nice 15/16" unit here:

https://baer.com/GM-Cast-Iron-.9375-...r-6150012.html

[dataway]

Yep, it appears the internals are still be made, but only available in a rebuilt core. I actually thought about buying a rebuilt MC just to get the internals.

[Dragncar]

So, if I get a stock type 15/16" MC what is involved in the switch ? Just get a rod from a factory manual brake car and swap the parts ?
I think I am going to get this Wilwood kit. Its the one they recommend for a car like mine drag racing. Its pretty basic, not too expensive.
https://www.summitracing.com/parts/wil-140-10996r
Thinking going with that and a stock type MC and maybe switching to the 400$ Wilwood unit at a later date.

[Greg Reid]

Originally Posted by Dragncar

Yeah, they do not want us rebuilding our stuff anymore. Thing is, they are making the parts, just not selling them to us. I can buy this one for 36$ that looks the same with a different top cover and no bleed screws. But its made in CHYNA.
https://www.amazon.com/Dorman-M71277...69+Pontiac+GTO

And thay have this one Amazon says fits for 57$, looks different but made in AMERICA ( I think?)
https://www.amazon.com/Centric-Parts...69+Pontiac+GTO
Out of spite I am buying the first one and if my original bore is not pitted, swap the seals.
Sad they can sell us a whole unit for 36$ but won't sell us the seals for 15$, They would make more profit selling the seals.
Its almost like you have to fight being a do it yourself guy these days.

Amazon says that the second one does not fit a 1968 GTO but does fit a 1969 GTO. Don't know what their parameters were for that conclusion.
Sort of related, I'm just in the middle of rebuilding my front disc brakes, converted by the previous owner. I didn't know what he used for the conversion so I just rolled the dice and ordered all lines, seals, bearings and caliper rebuild sets for a '69 GTO. It all fits perfectly.

[Scarebird]

Wilwood is overrated; Baer is a better set for the money.

This uses the stock 69-72 rotors with 99-04 Cobra calipers - all stuff you can get from NAPA or Rockauto... that and the goofy tapered Wilwood hubs grind my gears - whyTF don't they make them hub centric?

[Dragncar]

Originally Posted by Greg Reid

Amazon says that the second one does not fit a 1968 GTO but does fit a 1969 GTO. Don't know what their parameters were for that conclusion.
Sort of related, I'm just in the middle of rebuilding my front disc brakes, converted by the previous owner. I didn't know what he used for the conversion so I just rolled the dice and ordered all lines, seals, bearings and caliper rebuild sets for a '69 GTO. It all fits perfectly.

I have a set of stock 69 spindles, rotors and calipers. Very heavy it seems.
It all is probably frozen up after all these years.

[Greg Reid]

Mine were pretty crusty. Cleaned up well with some effort though.
All of this started with a way overdue shock absorber change... but I just couldn't ignore this mess any longer.
Sorry for the hijack. Back to topic!

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