View Full Version : Dual Master Cylinder Conversion

12-26-2013, 06:03 PM
I have a 1963 Falcon and want to replace my single reservoir brake master cylinder with a dual reservoir cylinder and am following this set of instructions:
http://www.cometeastcarclub.org/PDFs/Conversion_of_SingleBowl_to_Duel_BowlMasterCylinde r.pdf (http://www.cometeastcarclub.org/PDFs/Conversion_of_SingleBowl_to_Duel_BowlMasterCylinde r.pdf)

I went to NAPA after work and picked up the items on the list in the instructions, but after looking at the parts at home, nothing matches.

I bought a 1967 Ford Mustang Master Cylinder and two 8" x 3/16" brake lines. The holes on the master cylinder are 1/2" diameter and too big for the brake line fittings. Which is incorrect, the brake lines or the master cylinder?

The master cylinder holes have nipples,

... and the 3/6" holes on the tee fitting for the taillight switch have tapered cone-shaped bottoms that the brake lines do not want to tighten against. Should the tee adapters have nipple fittings like the master cylinder?

The other tee is straight though and has nothing for the brake line seats to push against. The brake lines say 3/16" x 8", but they also say JAPANESE. The tips of the brake lines are flat. Is that correct, or should they be conical?

12-26-2013, 07:00 PM
I did the same swap same directions.. Many here have as well.

Your master cylinder is correct and so are the lines, you must use an adapter to put the two together. The "nipples" in the master do not matter.
Both your T's are fine again you must use adapters to make the lines fit. If I remember there is one coupler you need that is very hard to find. The club bought a bunch of them just for that reason, I think Roger has them.
Think about it this way, all you are doing is providing a differant path for the fluid to follow, you are not regulating the flow or pressure just redirecting it.
If I remember correctly my rear brake line went straight to the master and the front come from the master to a T. The brake light switch goes into the top of the first T. Then the line splits one more time to accommodate the two front brake lines.. Hope this helps if not I'm sure you will get some more helpful tips.

Jeff W
12-26-2013, 11:08 PM
I didn't use the adapters. I cut the flare off of the end of the 3/16" tube and removed the existing tube nut, put on the correct size flare nut and re-flared the tube.

You have to get the correct size nuts for the 3/16" tube which is not easy to find.

The other thing to remember is that you need to do a "double flare" in the tube for brake lines.

The nut size is:1/2"-20 x 3/16" and 9/16"-18 x 3/16". You will need one of each.

This is the link where I normally purchase from, but I'm sure there are others:


I feel using these right sized nuts rather than adapters makes for a cleaner installation and have less potential for leaks... on the other hand it requires a good flaring tool and some patience to learn how to double flare.

Oh... if you want to use the original style brake light switch, you will need to find the fitting with two of the 3/8" inverted flares and one with 1/8" NPT.

like this:
I think the specs are written wrong - he tube size should be 3/16" but the nut is 3/8" for the inverted ends... unless I'm missing something.

For the T-fitting where you separate out for each front brake, all three have the 3/8" inverted flare.

Like this:

I think both of your T-fittings are incorrect.

Your lines look correct and will become conical (inverted flare) when you tighten them onto the matching fitting.

Thank you for doing this upgrade![BOW]

Kenny, Roger or anyone, please correct me if I have any of the sizes wrong. I think I wrote the sizes on the club parts bin before I handed it off.

12-26-2013, 11:30 PM
I was just looking to see if we'd posted images or something on this. Here's a PDF Kenny posted a couple years ago:

http://www.cometeastcarclub.org/PDFs/Conversion_of_SingleBowl_to_Duel_BowlMasterCylinde r.pdf

But the important thing to look for are that the fittings you use are internal flare and not pipe thread fittings (like you show in your pictures). If you have the old T with male 1/8" pipe and two 3/16" internal flare you can use this to add the hydraulic switch in the line - just need a 1/8" npt female/female coupler. I wholly recommend also what Jeff recommends for fittings to the M/C. Gotta be good with the flare tool though. Double-flares are not something to take lightly. You can use adapter fittings for a worse-case, don't care how it looks, non OCD install. Checking for leaks is essential no matter what your method of assembly.

I know there was more information on the site. If I find it, I'll post more.

12-26-2013, 11:47 PM
The thingI noticed after posting the above link and is also mentioned in the next is that Dick mentions nothing about the 3/16 to whatever size thread fitting is in the M/C. This thread addresses this a little better:


Jeff W
12-26-2013, 11:51 PM
Roger, are the tube nuts for 3/16" diameter brake line line actually 3/8"-24?

I think hey are but the more I look the more confused I become. I think it has something to do with the:BEER: beer

Jeff W
12-26-2013, 11:56 PM
Guess Ebay knows all:


3/16" fitting has 3/8" -24 threads.

Also much cheaper than Summit.

Jeff W
12-27-2013, 12:04 AM
Here are the adapters if you want to go that route -



BRAKE LINE ADAPTER FOR MASTER CYLINDER 9/16 18 male X 3/8 24 female:


12-27-2013, 03:43 AM
Hello, guys.

Thanks for the quick and detailed responses. That was great! It will take me a while to read through them thoroughly and follow all the links. I am surprised that the directions I have are so incomplete.

I'll track the needed parts down and will describe my progress with further updates and/or more questions.

What started this was Jeff's quote:
I bet if it wasn't covered up by the crumpled fender, you would still see the original single bowl master cylinder. I hope the driver/passengers are not badly hurt. This picture is a good motivation for all to upgrade to 1967 technology and install the dual master cylinder.

It kind of freaked me out. :)

12-27-2013, 01:24 PM
I hope you won't consider this too "in your face", but please see this thread:
regarding names. You're on here enough that I'm sure we all consider you a "Falcon Friend"!

Jeff W
12-27-2013, 02:03 PM
It kind of freaked me out. :)

That picture could have very well been my car excapt for a patch of good luck. The short story is; I was driving my Red Convertible down a very steep and busy hill and my front wheel cyclinder blew out. I lost 100% of my brakes. After a very scary few blocks, I was able to find a side street, took a wide turn and stopped on a small incline.

I am now the club advocate for this upgrade.

12-27-2013, 05:00 PM
I hope you won't consider this too "in your face", but please see this thread regarding names. You're on here enough that I'm sure we all consider you a "Falcon Friend"! Thanks.
Hello, Gene. I did you one better and sent Kenny my dues. I'm a paid Rainier Falcons Club Member! You guys can now say that you have members from coast to coast. Or at least to the lower Gulf Coast. Just don't start razzin' me about never showing up for the meetings. I in-putted some info to the signature section. Let's see if anything shows up at the base of this post.

I went to O'Reilly's auto parts today at lunch. They pointed out that the two outlets from my master cylinder were different sizes (7/16” and ˝”), and that my brake lines with a Japanese 3/16” thread fitting were not the same as 3/16” U.S. thread fittings. Neither O'Reilly or NAPA had a 1/2" to 3/16" reducer, but O'Reilly had 1/2" to 1/4" and 7/16" to 3/16" reducers. So, I wound up with two sizes of brake lines, 1/4" and 3/16".

The 3/16" line goes to a flaired 3/16" tee for the front brakes. The 1/4" line goes to a 1/4" flaired coupling on a tee. The other slots on the tee take the brakelight switch and the 3/16" line from the rear brakes.

Here is the assembly. The lines need to be bent in creative loops, but I believe that it will fly. I will install it when my car comes back from the paint shop (Maybe in a couple of weeks?). This should have been done before painting the car, but ......

12-27-2013, 06:39 PM
I used a broom handle to work my lines into a coil. Worked good, just go slow and the soft metal will make the big curve without kinking.

12-27-2013, 06:50 PM
WELCOME to the club! I'll be proud to proclaim our "coast to coast" membership. Thank you! Your new signature looks good.
I too have the dual master cylinder conversion on my car. As a matter of fact, I beleive Kenny and Jeff actually performed the conversion on my car whilst a Tech Day was in progress at my house, as the club will usually do for members as a "service" if they supply the MC. So, maybe you should consider showing up for a Tech Day(?). OK..... maybe not. Kind of a long way (3103 mi) and I'd hate to see you do that on a single MC.

12-27-2013, 07:26 PM
Hello, Gene.

I really do have visions of hopping in this little car and just driving for a couple of weeks. When I got out of the Navy in 1983, I drove my 1977 Dodge Colt from Norfolk, VA, to Montreal Canada and then down to Orlando. I saw Mammoth Caverns in KY, camped on a mountain top in VT, and saw Niagara Falls. I'd love to do it again, but this time head out west while driving my Falcon. North Texas, the Great Plains, the Rockies, the High Sierras. My little Falcon powering up Pikes Peak. Mount St. Helens. To see giant Red Woods. Oooooh, that would be nice.

Back to the brake line fittings. Should I wrap all the threads with Teflon tape? I didn't see that mentioned anywhere.

12-28-2013, 12:56 AM
Never put anything like teflon tape or pipe dope on flared fittings. The seal is made when the nut presses down on the flare. If you look at the female half of the fitting you'll see where the flare seats and makes contact when the nut pushes down on it.

The threads on the nut don't need to be sealed because if fluid is getting past the flare seal, you need to snug it a little tighter or make sure the double flare looks like it's correct.

Jeff W
12-28-2013, 01:05 AM
I think the NPT threads on the brake light switch would need some teflon tape.

Did you get different T fittings than the guys you described? I'm still not clear on the adapter to T connections. Although if may feel like NPT and straight threads screw together... it is not correct.

12-28-2013, 05:23 AM
Did you get different T fittings than the guys you described? I'm still not clear on the adapter to T connections. Although if may feel like NPT and straight threads screw together... it is not correct.

Wikipedia says: "National Pipe Thread Taper (NPT) is a U.S. standard for tapered threads used on threaded pipes and fittings. In contrast to straight threads that are found on a bolt, a taper thread will pull tight and therefore make a fluid-tight seal."

Hello, Jeff.

Due to parts availability, I used two different-sized adapters for the master cylinder outlets with male NPT threads and flaired female threads. The fitting on the left goes from a 1/2" hole to a 1/4" brake line. The one on the right goes from a 7/16" hole to a 3/16" brake line.

Tee #1 was complicated because it joins two different sized brake lines and the brake-light switch. Tee #1 seems to have three female NPT inlets. The brake-light switch and the two flaired adapters feel like they are screwing in correctly.

Here is a side view of the complicated Tee #1. You can see the flaired fitting on the inside of Tee #2 in the background.

12-28-2013, 08:59 AM
Whoops! I just spotted a potential problem.

These are the adapters that screw into the master cylinder inlets.

In my previous post I had called them NPT pipe thread fittings. But, .... they screw into holes for flair fittings. The smaller fitting on the left has a dish-shaped end, so it should be good for its flair coupling. The one on the right has a flat end that must be for a pipe thread and it needs to be made for a flair fitting.

I got into the Zone, ... Auto Zone.

I replaced both of the couplings that screw into the master cylinder. The new one on the left has a longer shaft ($2.49). The one on the right now has the correct flair fitting on both ends ($1.99).

Here are what the new couplings look like:

12-28-2013, 11:21 AM
If you do have to use sealant on any of the NPT threads, be careful to not get anything past the end of the nut. You don't want a piece getting into the system. I've heard Permatex Thread Sealant is resistant to brake fluid and may be a better option. The white teflon tape just turns to goo if you get brake fluid on it.

I've just done everything possible to never use sealant on a brake system. I got rid of the pressure light switch by putting a mechanical one on the brake pedal under the dash.

Jeff W
12-28-2013, 10:08 PM
I think that all should work. Let us know if you have problems. Now that you are a Rainier member we can send you any needed fitting. Labor is a bit of a challenge considering your location.

12-29-2013, 07:34 AM
A final (hopefully) revision:

After further reflection, I decided that it would be better to eliminate the two NPT adapters on the brass tee for the brake light switch and bought an “Allstar Performance 3/16" Inverted Female Tee Brass 3/16 Tube T 1/8 gauge port” off e-bay for $8.49 + free postage. Manufacturer's part number: ALL50137. I hope that this is correct.
I also bought a “brake line adapter for master cylinder 9/16” 18 thread male X 3/8” 24 female adapter” off e-bay for $6.80 + $3.08 postage, to allow me to run a 3/16” brake line from the large hole on the master cylinder (a 3/16" fitting has 3/8" -24 threads). http://www.ebay.com/itm/BRAKE-LINE-ADAPTER-FOR-MASTER-CYLINDER-9-16-18-male-X-3-8-24-female-/231006105707?pt=Motors_Car_Truck_Parts_Accessories&hash=item35c909706b&vxp=mtr (http://www.ebay.com/itm/BRAKE-LINE-ADAPTER-FOR-MASTER-CYLINDER-9-16-18-male-X-3-8-24-female-/231006105707?pt=Motors_Car_Truck_Parts_Accessories&hash=item35c909706b&vxp=mtr)


Jeff W
12-29-2013, 12:04 PM
Now I feel much better;) This is a good set -up.

Everyone can (and is allowed) to do their own thing, but less Rube Goldberg is best when it comes to safety.

Be sure to:
1) use the push rod out of your old master cylinder. It usually takes some muscle to get it out. The new rod is too long.
2) bench bleed the new MC before installation.

Wikipedia says:
"Reuben Garrett Lucius "Rube" Goldberg (July 4, 1883 – December 7, 1970) was an American cartoonist, sculptor, author, engineer and inventor. He is best known for a series of popular cartoons depicting complex gadgets that perform simple tasks in indirect, convoluted ways..."

12-31-2013, 12:04 AM
Noticed the earlier image showing the nut hard-up against the M/C and was going to (prematurely) comment, but decided to read through all the rest. You seem to have it all figured out using the correct adapter fittings.

Having now done about a dozen of these conversions it's so much easier to do than it is to explain. I/we should really do a full-fledged PDF of this step-by-step with detailed pics. The original PDF posted is good, but leaves out a couple important details, like these fittings for one - or the use of 3/16 brake like (which normally comes with the 3/8-24 threads), but adapting them to the two larger nuts. Or options to negate the pressure switch. Real soon now.

And, now, just to clarify fittings and their use... pipe threads are tapered. The teflon or "sealant" are not supposed to act as the seal. The taper provides this. The issue is keeping friction low so you can force the two threads together until they self-seal before they gall (the melting, of sorts, of similar materials by heat or friction). On some materials, like stainless, these similar materials will gall very quickly without a sealant with Teflon, and in some cases still will to some degree. So the use of a Loctite-based Teflon sealer will cure and harden in the absence of air and minimize leaks. Usually the use of sealant, as a sealant, is deemed necessary when the male and female parts have worn or expanded beyond their wear limit - with mixed results.

Teflon tape, if used, needs to begin up about one thread from the end of the male threaded end to keep it out of the system. But great care needs to be given if Teflon tape has been used before. Every strand of it needs to be removed, since even though it is used correctly the first time, the second use of the threaded parts will work these strands forward and inward - towards the flow of fluid - and into the working bits.

Inverted flares need no sealant, as Kenny indicated. The flare (male against female) cause the seal. One issue I have seen when using these large nuts but with 3/16" line size is that the male part (like that inside the M/C) is assuming the larger tubing flare, not the 3/16" size flare. I had one install where I could not get a good seal. So - just putting this out there that it "may be" better to use the adapter fittings as opposed to the large nuts with 3/16" holes. Depends on the machining of the flare inside the M/C.

Since flare fittings don't expand with use, like pipe-thread fittings do, they are a positive seal every time you loosen and tighten them.

So that's all I got to say about that. Happy braking!


12-31-2013, 03:33 AM
Hello, Roger.

You talked about lubricating pipe threads. Would dipping the brake switch threads in brake fluid work?

I made another revision yesterday. I went to NAPA and bought two "Brake Fit Tube Nuts" (#641-3296 and #641-3322) for 69 cents each and then went to "Just Brakes" and had them attached.

The mechanic used a tube cutter to cut the ends off the brake lines. He re-flared the lines with a "bubble flare" and said that this was the flare that my 8-inch brake lines had come with. I made a brief look at the internet about the subject and saw the comment: "Automotive brake lines are always a 45 degree double flare or a DIN (bubble) flare." Here are my bubble flares:

Here is an internet photo comparing the bubble and double flares. I need to read more about the difference between the two:

Here are what they look like attached. This eliminated two adapters. If the custom flare fittings leak, I can always get a couple of new brake lines and try the adapters.

12-31-2013, 10:03 PM
I've never seen bubble flares on a car before, so I'd need to study those too. Our cars used 45 double flares.

As for brake fluid as a lube, as long as when you tighten it, and all is said and done, if you don't have any hint of a leak, you're probably OK.

Happy new year - there.

12-31-2013, 11:26 PM
I've never dealt with bubble flairs but they came into standard in the mid-80s. Maybe even in metric systems. Do they use the same fittings as the double flair?

01-01-2014, 06:28 AM
A NAPA shop near my house has a machine shop. I will visit there tomorrow and see if they can put a "45 degree double flare" on the ends of the brake lines.

Description read on internet: "Inverted Flare or 45 is on all standard automotive applications, and cars and trucks from the 30's to mid 80's have inverted flare fittings at all the connections. Inverted flare is a single nut that uses a 45 degree double flare. This flare is lapped over so the tube is double thickness at the end."

See: http://inlinetube.com/install%20instructions/Instruct%20tube%20flaring%2045.htm (http://inlinetube.com/install%20instructions/Instruct%20tube%20flaring%2045.htm)

01-01-2014, 11:54 AM
For about $50 (on the cheap end) you can get a double flaring tool kit and pipe cutter. I've always flared brake lines myself and think it's really easy. After watching some YouTube videos and practicing a few times, it's not difficult to get the hang of. And you'll have the tool when you need it again. And you will probably need it again down the road.

Old lines tend to seize to the nut and will twist as you try to remove them. The wheel cylinders are notorious for this and if they are original, you should put them on your list of things to replace. That's what blew out on Jeff's wagon. Even with a dual master cylinder, the rest of the system should be tended to. Check the rubber hoses going to the front wheels and rear distribution block on the differential. If they're getting dry and cracking...replace.

01-01-2014, 08:26 PM
If you decide to buy a double flaring set, I would advise you spend a few extra bucks and buy a good quality brand. Search the internet on what is the best for the buck. I bought a cheaper version and the flares were bad and leaked. Bought a better set and they work great. I agree with Kenny that it is a good purchase and the tubing cutter along with a decent tubing bender will get used again and again. Larry

01-03-2014, 09:27 AM
Here is my updated configuration. The brake lines attach directly to the master cylinder and the only pipe thread is for the hydraulic brake light switch.

The owner of the Meineke car care center near my house used a hand-held hydraulic press to make the flare in my brake lines, and he did it for free! He's a good guy.


Here is my final parts list for the conversion:
From NAPA auto parts:
Part Number M2036 New 1967 Ford Mustang Master Cylinder, $63.49
Part Number SL134 Stoplight Switch, 1/8-NPT, 27 threads per inch, $8.99
Part Number 641-3296, Brake Fit Tube Nut, $0.69
Part Number 641-3322, Brake Fit Tube Nut, $0.69

From O’Reilly auto parts.
Part Number PA-308, 8” x 3/16” brake line with a fitting on each end (2 X $4.99), $8.98
Part Number 130333, 3/16” Union Tee (3/16" fitting has 3/8" - 24 threads), $5.99

From e-bay:
Part Number: ALL50137, AllStar Performance 3/16" Inverted Female Brass Tee Brass with a 1/8” NPT gauge port, $8.49 + free postage
Grand Total: $88.83.

Trivia: I used a bathroom scale and found that the 1967 Mustang master cylinder weighs 5.2 lbs.

The clerk told me that it was actually less expensive for me to buy a new rather than a reconditioned master cylinder because I did not have an old master cylinder to turn it for the core fee. NAPA Master Cylinder for 1967 Mustang with manual brakes: http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Brake-Master-Cylinder-New/_/R-NMAM2036_0358750724 (http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Brake-Master-Cylinder-New/_/R-NMAM2036_0358750724)

“Beginning in 1967, Ford went to the federally mandated dual braking system, which provides braking pressure should the front or rear system fail. This is a dual reservoir master cylinder, with separate reservoirs feeding master cylinder bores positioned in tandem. Stepping on the brake pedal pressurizes separate front and rear brake systems.”
See: http://www.mustangmonthly.com/techarticles/mump_0209_ford_mustang_brakes/photo_03.html

01-03-2014, 02:18 PM
Nice work so far.

“Beginning in 1967, Ford went to the federally mandated dual braking system, which provides braking pressure should the front or rear system fail. This is a dual reservoir master cylinder, with separate reservoirs feeding master cylinder bores positioned in tandem. Stepping on the brake pedal pressurizes separate front and rear brake systems.”
See: http://www.mustangmonthly.com/techarticles/mump_0209_ford_mustang_brakes/photo_03.html

I'm always amazed at all the car technologies that we have because the government pressed the issue. Disk brakes, fuel injection, dual circuit master, air bags, seat belts.

01-21-2014, 08:21 PM
For several reasons, I wimped out and let my local Meineke shop install the dual master cylinder.

A 1967 master cylinder in a 1963 Falcon. Fifty years ago, this would have been "The Falcon of the Future, .... Today!" My Futura is now (or would have been) truly Futuristic! Notice the curly bends in the brake lines:

Lines off dual cylinder:

Meineke said that they ran into a problem (without problems things would be too easy). The existing brake lines were not fitting correctly because the nuts were rounded and the flares were old. When they trimmed the ends to add new flares and nuts, the lines were not long enough. They used a pair of flared adapters to graft new lengths of brake line onto the existing lines. See the brass-colored fitting on the right front brake line in the picture:

Here is a close up of that fitting:

They also added a coupling to the brake line going to the rear:

My engine and engine compartment are all dusty from the car being sanded while it was at the paint shop. I will wash them with a wet sponge this weekend and try to clean them up.

Jeff W
01-21-2014, 08:46 PM
I should have mentioned that part. We used a few of those double flair couplers on installations as well. Same reason... Kenny had forgotten his brake line lengthening tool so we made do:banana:

Nice work and thank you:BEER:

01-21-2014, 11:06 PM
I for one can not over stress the need to have good, trustworthy brakes, so this is a good first step. I would have though, had I had what they had at their disposal (a rack), run a new line all the way to the back and to the passenger wheel. We're talking less that 15' of line. Extra joints I'm not a fan of. These steel lines after 50 years are sure to be less than pretty internally and externally, since brake fluid is both corrosive and collects moisture. Anyway, something to consider. I did both my wagon and Ranchero - just because. Watch them closely. If you see any seepage, buy a coil of 3/16" brake line(in bulk) and have these replaced.

Or drive it up here and we'll make it a tech day! :banana:


01-22-2014, 12:20 AM
Thanks for posting all this stuff up as I am just in the process of doing this and finding this thread just made searching so easy

01-22-2014, 03:50 AM
... run a new line all the way to the back and to the passenger wheel.

I agree, Roger. From the mechanic's perspective, I asked him to replace the master cylinder and that is what he tried to limit the job to. Customers can sometimes freak out if a mechanic replaces a lot more than the customer originally asked for.

My brakes are in great shape now with new shoes, drums, wheel cylinders, and now a master cylinder. I will change the brake lines (maybe with stainless steel?) whenever the brakes need to be redone again.

But, I will never need to re-do the brakes unless I start driving the car and racking up some mileage! Everything seems to be fixed now (knock on wood), so my goal is to add at least 5,000 miles to the odometer this year. Adding 10,000 would really make me happy. [yay]


01-22-2014, 01:24 PM
Attached image

It's too late... :NERVOUS:

07-22-2014, 08:33 AM
Whew...just pounded through all these threads. Roger....any more thoughts about that finalized updated pdf you mentioned below...?? :NERVOUS:

I'm hoping to finally have the rear axle done soon and need to order some brake line, fittings and the cutting and flare tools. I figured it would be a good place to start with new line, fittings and bending since it's all up on the bench now-and everything else on the brake system is bran new. Then...work my way forward as things progress. BUT...so many options just on brake line.

Any comments on what kind of brake line to buy if I'm going to replace all the brake lines?
It seems like standard steel brake line is just fine? But some is soft, some hard, some copper nickel coated, some more flexible, also ebay options...and I'm seeing the Eastwood flaring tool is really expensive- and on the other hand I see super cheap ones. I assume there is a good one in the middle? Appreciate any advice.

07-22-2014, 02:05 PM
any more thoughts about that finalized updated pdf you mentioned...?? :NERVOUS:

I know, probably would be a good idea. RSN (Real Soon Now).

I'm not sure what to offer on the line, other than my experience. I order 25-50' spools of standard steel line from Napa and make up all mine that way, but there are advantages to SS and the other new coated lines. Just have no experience with them - though I have tried making a new flare on the coated. It didn't work out right using the standard double flaring tool. Probably wants the high-end flaring tool to do it right. The standard steel line will eventually rust away like the original, but I'll be long gone by then.

I assume you are just doing a standard single-to-dual conversion. No discs. If so, with the early brake light switch being hydraulic, this is the only variation between the two systems (pre and post 64). On pre-64 most convert to mechanical switch inside the car by either adapting to the '65 style switch or removing the rubber stop for the brake pedal and putting a switch in its place. Either way works, though the '65 switch requires a '65 pedal or a modified bolt to hook the switch and M/C rod onto. That's what I did to my Ranchero. Finding the '65 pedal would have been easier in hind-sight. You can also retain the hydraulic switch, but it will require an 1/8" pipe thread (female to female) coupler and a tee (1/8" NPT and two 3/16" inverted flare) to utilize it.

It's really pretty simple and as a club we're willing to help. Just arrange a tech day. [thumb]

07-22-2014, 09:37 PM
Tech day I'm in. It would be nice to go help someone else as the last three or four tech days have been over here!

04-21-2016, 05:30 PM
Did anybody ever finish their project? I searched for an installed example but have not fond one. I'm puzzled over the placement of the old lines. Mine like the picture in the instructions will to be connected in the front of the new unit not to the side. This is for my 1963 Comet the Falcons and Mustangs groups are big on this upgrade.

04-21-2016, 05:44 PM
I've always recommended this document to get you started. And they are doing it on a Comet too!

http://www.cometeastcarclub.org/PDFs/Conversion_of_SingleBowl_to_Duel_BowlMasterCylinde r.pdf

04-21-2016, 06:05 PM
I've always recommended this document to get you started. And they are doing it on a Comet too!

http://www.cometeastcarclub.org/PDFs/Conversion_of_SingleBowl_to_Duel_BowlMasterCylinde r.pdf

That's where I started. After reading the entire thread I have a really good idea of the cleanest way to do this.
It's the dressing of the lines from side to front that's unclear. Will the new master fit behind the old connections? Or is it one more thing not to sweat because the old lines are somewhat moveable.

04-21-2016, 06:30 PM
It all depends how good your old lines are as to how well they'll move about. I've always used new lines on mine but have done a couple with existing lines. Feed those to the tee with 3-way 3/16 flare and new short line to M/C. If using hydraulic switch I used a 3/16 tee, but one branch was 1/8" pipe thread and still use a new short line to the M/C. The M/C lines both need larger fittings anyway, so get the 3/16 line to correct fitting size nuts and make a couple 12" lines and curl them into about 1.5" spools to give you nice looking adapter lines to the two tees. It doesn't matter if the brake switch goes into the front or rear of the M/C and the old lines hang out under the new M/C with these new short lines going down to them.

Don with Granddad's Falcon just got his plumbed last weekend so maybe he can post a picture. It will match what I last described.

Jeff W
04-21-2016, 07:51 PM
Dennis has some pictures of his completed job about ten entries above this. That is exactly what was done to a few of our members cars during tech days when existing lines were used.

as Roger stated, the best route is all new lines, this coupler idea is a close second.

04-21-2016, 08:39 PM
Darn...mine is "almost" done, but you know how that goes. Hopefully I can test it this weekend or next, but I don't want to publish any pics until then. Looks really nice though! (Thanks to Larry and Roger and Jeff and Kenny...[BOW][BOW][BOW][BOW])

05-08-2016, 07:38 PM
Here are some pics of my dual master install... believe it or not does fit.
It's all bled and nothing leaks...but I still need to adjust the brakes, clutch, and tranny linkage before I can take it for a test drive.

05-09-2016, 10:55 PM
Nice job bending and looping those lines! Looks like a clean install.

05-09-2016, 11:29 PM
Mostly due to Larry and Roger for sure...but I did redo a bend or two to get it all to line up with the clips[yay]

Jeff W
08-09-2016, 10:24 PM
This photo was sent to me by a friend that was at Hot August Nights in Reno. Is this some sort of quad master cylinder or am I missing something? Not sure exactly what I am looking at.

I am guessing it is in a 63 convertible by the toy on the air cleaner.

08-10-2016, 07:23 AM
Could be a dual MC and a dual hydraulic clutch? But why would you need a dual clutch assembly?? Interesting. :confused:

08-10-2016, 10:10 AM
Really looks like 4 dual masters, but it's not really clear. I guess he figured that with all the restrictions he had with shock towers he'd capitalize on the available space without those and just go crazy, uh, I mean, rationally exuberant. Or maybe he's an engineer at Boeing and he's built in multiple redundancy.

08-10-2016, 11:16 AM
Another idea is that he might have a balance bar to adjust front-to-rear brake bias. A fairly typical race car setup uses two master cylinders, side by side, and a horizontal bar which activates both. One MC is for front brakes, the other for rear. The front-to-rear balance can then be adjusted by revising where the brake pedal presses on the bar.