1966 duel master break

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abaucom
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1966 duel master break

Post by abaucom »

After all these years there must be a way to retro the 1966 brake master to duel to improve safety.

1969, driving my 1963 Bird, hit the brakes & nothing happened. Managed to stop the car without hitting another car. Scared the hell out of me. Brake master shot, lost fluid. Last year started my 1966 after six months winter storage. Before winter storage all fluids checked. Bird started fine, put in into drive, no brakes and ran into a wall. Thousands in damage and a year later picking it up from a restoration shop in a week. Break master cylinder replaced, brake booster appears to be in good shape, I am afraid to drive my beautiful 1966.

There must be a way to retro duel master brake stuff to make Flair Birds safer. Yes, I have gone through years of threads, not one solution I have found to send to my mechanic.

Help. Perhaps you do not know the fear when you are driving your T-Bird, hit the brakes, nothing happens and your car is out of control. It is a terrifying experience.
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Peddller
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Re: 1966 duel master break

Post by Peddller »

I know this is a popular modification and I understand the benefit of the dual chamber master cylinder. The thing is I don't have a classic car with a dual chamber and have never had a problem. Think about the millions of cars that ran all over the country with the old techknowledgey without daily crashes. I think way too much is made of this and for those cars that seem to suffer abnormally high failures there may be other factors at play.
Bill Clark
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64ZCODE
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Re: 1966 duel master break

Post by 64ZCODE »

Hi all. The dual master is a desirable improvement. I purchased one for my ‘64 that is designed to fit under the shock tower brace and work with the stock booster. I haven’t installed it yet and am pretty sure that when I do, I will have to replace brake lines. But that’s all knowable and doable and will further improve the car.

I did replace the single master and am on track to replace rubber brake hoses. I keep a close watch for leaks and feel safe driving the car. However, I recognize there is risk. In fact, years ago I was a passenger in a ‘56 Buick with a single master when a brake hose failed. The quick reaction of the driver prevented what could have been a serious situation.

Doug
1964 TBird Hardtop
1969 Galaxie 500 Convertible
1990 Mustang 5.0 LX
1974 Porsche 914 2.0
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paulr
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Re: 1966 duel master break

Post by paulr »

Doug makes a point that should be thought about. Why weren't there millions of single-circuit induced brake failures all those decades we were growing up. Why is it such a major topic of fear and controversy today.

In the 60s, for example, mechanics, gas stations attendants, heck--a lot of average Joe car owners, were really tuned into maintenance signals. Today, people are tuned into whether their new car has Instagram or not. Cripes! When North American roads were filled with brakes like these, there was a general knowledge base among all about function and safety. Today, there's just this forum and a few remaining professional mechanics. The remark "other factors possibly at play" is where to focus. If you hire a mechanic to put in a new master cylinder, that's probably the only factor that will be examined. How often is the car being driven (and stopped)? Are there long sitting intervals, say winters, etc? Is anyone routinely looking at the quality and level of the fluid?

I bought a car that had sat for maybe 2 years and stupidly I drove it 300 miles home. I enjoyed driving it in the city while I dug into repairs, ignoring that the brakes should have been job #1. It was stopping ok...until it didn't after about a month. It took that long for the dried out old seals to loosen up and shred, in an intersection, in traffic, down a steep slope. So, shame on me. I learned it's my job to be that 60s era maintenance man.
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Richard
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Re: 1966 duel master break

Post by Richard »

I lost my brakes and had the sense to hit the emergency brake to stop. Had the master replaced with a duel master. Bought it from Pat Wilson. For my set up I had to make a notch in the cross brace for it to fit. Seen others that didnt need the notch,guess they maybe have a different brake booster that isnt as big..Good luck..
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paulr
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Re: 1966 duel master break

Post by paulr »

Richard, I’ve only seen 65/66s with original boosters where the brace had to be altered in one or another way to fit the dual circuit master in, like yours. I’d like to see info or links on suitable duals that fit in the small space with the brace left as is.
Paul
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Richard
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Re: 1966 duel master break

Post by Richard »

paulr wrote: Sat May 11, 2019 9:57 am Richard, I’ve only seen 65/66s with original boosters where the brace had to be altered in one or another way to fit the dual circuit master in, like yours. I’d like to see info or links on suitable duals that fit in the small space with the brace left as is.
Paul, Just went to garage to check and my booster is the crimped type. I do remember reading on this forum in the past that there is a crimped type and a banded type. Is my crimped type an original do you think?

The brace was an issue ,the shop that installed the master hacked the brace. I had them buy me another from Pat Wilson and cut it myself. I do not have the skills with cars the way I would like. But I am a studio/set builder carpenter by trade for 40 years and do have some skills so I did a nice cut to the new brace..Retired now though.. :smile:
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paulr
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Re: 1966 duel master break

Post by paulr »

Richard wrote: Sat May 11, 2019 10:26 am
paulr wrote: Sat May 11, 2019 9:57 am Richard, I’ve only seen 65/66s with original boosters where the brace had to be altered in one or another way to fit the dual circuit master in, like yours. I’d like to see info or links on suitable duals that fit in the small space with the brace left as is.
Paul, Just went to garage to check and my booster is the crimped type. I do remember reading on this forum in the past that there is a crimped type and a banded type. Is my crimped type an original do you think?
You have an original MY65 style I recall from one of your photos. There is only the one style for 65 and 66 and it’s huge compared to 64.

The posted discussions about banded vs. crimped apply to the old 64 and even older 64/63 style.
Paul
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Terry64HT
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Re: 1966 duel master break

Post by Terry64HT »

Al, you haven’t had much luck with answers to your question, so I thought I’d chime in. I don’t have experience with 66’s, but while doing research to make my 64 conversion, I came across quite a bit of info about 65’s and 66’s. A dual master cylinder from either a disc/drum 67 Tbird or 73 Mustang will work, although the 67 Tbird seems to be a better choice because it’s a bit shorter and the ports are more conveniently placed. On both dual masters the ports are a different size, so either adapters will be needed or (a better option) the flare fittings on the lines will need to be changed. When I did mine, I replaced the lines with easily bendable copper/nickel within the engine bay for a cleaner look and easier installation.
While the bores on both of these masters is slightly different to your original, it doesn’t seem to be enough to make a difference in performance. The bolt pattern to the booster is the same and there will be no need to change the rod length. Your original proportioning valve, located on the inner fender below the master is not worth keeping and should be replaced with an adjustable one of a more modern design. There is no need to make any changes to your brake switch or any of the wheel components.
All parts, either new or rebuilt are available from sources like Rock Auto and mechanically it is a fairly simple thing to do. I know with my 64, I had to change the shock tower brace to one from a 65, but I don’t have any idea how things fit for a 66. I think worse case would be a slight modification to the brace itself.
Hope this helps
Terry
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Re: 1966 duel master break

Post by 64ZCODE »

Hi Terry. You mention replacing brake lines within the engine bay. Were you able to splice new lines to the existing lines or did you replace the lines all the way to the wheels?

Reason I ask is I’ve read that splicing is a no no but also see there are ways to do it.

Doug
1964 TBird Hardtop
1969 Galaxie 500 Convertible
1990 Mustang 5.0 LX
1974 Porsche 914 2.0
Terry64HT
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Re: 1966 duel master break

Post by Terry64HT »

I replaced the lines for the front wheels all the way to the rubber lines at the wheels. One of these was in poor shape and I replaced it also. The line for the left front wheel could be done with a single piece, but the passenger side goes across the firewall behind the engine and I did it in two pieces with a splice below the heater motor. There is already a splice in the line to the rear behind the inner fender (at least on mine there was), so I just replaced to that point. The lines to the driver's side wheel and rear are so short it's not worth trying to splice. I bought premade lines a bit longer than I needed with fittings of the various size I needed for the ends attached to the vehicle and then just redid the fittings for the ends that attached to the master.
I'm not sure about your comment about splices being a no no, they are just a pair of flare fittings into a female/female fitting instead of a female to something else. There is no reason why they should leak.
As I said in my post, I used copper/nickel lines that are very flexible and easy to make a double flare connection.
Terry
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Re: 1966 duel master break

Post by 64ZCODE »

Good info, thanks Terry. I’ve heard from DJ Dan that the Cu/Ni line is a joy to work with and will make any line replacement project much easier. Doug
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RedBird64
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Re: 1966 duel master break

Post by RedBird64 »

Dual MC is like car ins.
I've paid out thousands and thousands of dollars on premiums but never needed it.

Scott
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Rt.146
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Re: 1966 duel master brake cylinder

Post by Rt.146 »

What would be the consensus on what duel master brake cylinder will work on the 66 Bird with the least amount of alteration to the car, does such an item exist for the 66? Some wrote Wilson may have it for the 64-65; 64 has drums, 65 disc/drums, would the cup size of the duel chamber be OK for drums and disc?
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Re: 1966 duel master break

Post by RedBird64 »

You don't need to worry about resevoir size or capacity. The issue are having residual valves in the MC, the correct size piston and connections on the side you need. So anyone doing the conversion to a dual MC needs to source a drum/drum MC for a stock 64 or a drum/disc MC for a 65-66 and watch the port locations.
I have a 69 Mustang MC for my car with 65~67 brakes. It has the correct internals.

Scott
1964 Coupe Wimbledon white/Rangoon Red w/black int. Owned for 42 years. It was my folks car before that (second owners). VTCI # 12013.
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