55 Master Cylinder Question

[gmsnowball]

New to the forum and new owner of a 55 T Bird. Anyone seen a 55 master cylinder that is rectangular in shape with two brake lines coming out of the master cylinder? Looks like it has two pistons or ports in the master cylinder. I can't find anything that looks like it on the T Bird sites. The car has been in dry covered storage for over 30 years and of course the master cylinder was dry as a bone. It has a rectangular lid that has a long bolt that holds the cap on. I had to remove the drivers side hood latch to get the cap off. It also has 56 side wings and what I believe to be a 312 with a big Holley carb on it. It clearly has a 312 intake and exhaust manifolds but I will have to see the crank to find out if it has a notch in it to determine if it is really a 312 or not. I must admit the master cylinder has me stumped. Might just put a 67 Mustang dual bowl on it like I did my Comets and Ranchero's. Any help would be appreciated.

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[Tater Salad]

Here's one from 55. Not sure what that one is

 

[Pete986]

The ‘67 Master cylinder bolts up?
That’s good to know. I put one on my ‘66 Mustang. Never looked back. Best modifications I ever did!

 

[cokefirst]

Here's one from 55. Not sure what that one is

That master cylinder appears to be from a 1960 or so International Scout or Travelall and is intended as a combination brake and clutch unit. I have no idea why someone would do that, but I suspect that the firewall was cut and modified for the installation. Is this a standard transmission car? It is not a dual master cylinder as in it does not have a separate compartment for the front and rear brakes.

 

[gmsnowball]

That master cylinder appears to be from a 1960 or so International Scout or Travelall and is intended as a combination brake and clutch unit. I have no idea why someone would do that, but I suspect that the firewall was cut and modified for the installation. Is this a standard transmission car? It is not a dual master cylinder as in it does not have a separate compartment for the front and rear brakes.

I will check tomorrow but I think both hydraulic lines look like they went to the brakes. It would be cool if the clutch was hydraulic but I doubt it. I could not find a T or hydraulic brake light switch in line. I have not looked under the dash so I don't know what is actually under there. It is a manual transmission with overdrive. If the dash isn't hacked up I will most likely put a 67 Mustang dual bowl master cylinder in it with nickel copper alloy brake lines. I have used that set up on several Comets and Falcons with good success. The car was way ahead of its time with several modifications, later year model parts, aftermarket items and chrome. I want to replace the entire brake system with new parts, wheel cylinders, shoes, hardware, rubber hoses, wheel bearings, seals, etc even though the drums look new. Any recommendations where to get the parts I need to do this?

 

[cokefirst]

Several of the Thunderbird parts suppliers have the brake parts you need. If originality is not your thing, I understand that Speedway Motors has a Willwood disc brake conversion kit for the 1955 Thunderbird for about $650. Mac's has a nice kit for 4 wheel drum brake cars for about $200. I will keep my personal opinion to myself as I believe the owner of the vehicle has the right to modify it as suits him. Several suppliers including Larry's and Macs have the brake line kits in both standard and stainless steel.

As far as the master cylinder you nave now, perhaps the person modified it so that the brake pedal operated both pistons so that one operated the front brake and the other the rear. The distribution block would have to have been modified so that the two systems for front and rear brakes would be separate. In any case, that master cylinder was designed to be a single reservoir for the brake and clutch master cylinders.

 

[BillM]

No vehicles had dual line master cylinders till the late sixties when it was mandated by the federal goverment. This was a safety measure, some vehicles as was stated above had a master cylinder and clutch arrangement but one of the lines was never intended to go to the brakes

 

[1957Bird]

Prestigue T Bird in Ca has a real nice dual res master kit. Includes new adjustable push rod and prebent lines to do the installation. Reasonable price and great set of directions.
you really need to do the new push rod to get full benefit of new dual cyl.
took less than 2 hrs

 

[gmsnowball]

Thanks for the replies. I have installed dual bowl master cylinders on several 64 and 65 Falcons and Comets. Easy modification with good results. I use nickel copper alloy brake lines as they are very easy to work with a have a very high burst rating and look really good. I haven't had a chance to get back to my shop to see what is actually under the dash. If someone did install this from an International they did a good job. You can't tell it doesn't look stock from the engine bay. May explain why the clutch went all the way to the floor when I pushed the pedal. Who would have thought to do this mod way back when? This really has me curious now.

 

[gmsnowball]

That master cylinder appears to be from a 1960 or so International Scout or Travelall and is intended as a combination brake and clutch unit. I have no idea why someone would do that, but I suspect that the firewall was cut and modified for the installation. Is this a standard transmission car? It is not a dual master cylinder as in it does not have a separate compartment for the front and rear brakes.

Bingo !!!, you sir are correct. I just checked on line and the exact master cylinder is a 61 International Travellall. Can't believe they still sell them. Now, what to do? Keep it as is, go back stock, a Mustang dual bowl or Willwood disc upgrade?

Thanks, I would have never thought of the car having a hydraulic clutch. The car does have several interesting modifications and upgrades as well as a very interesting and colorful past.

 

[cokefirst]

Bingo !!!, you sir are correct. I just checked on line and the exact master cylinder is a 61 International Travellall. Can't believe they still sell them. Now, what to do? Keep it as is, go back stock, a Mustang dual bowl or Wilwood disc upgrade?

Thanks, I would have never thought of the car having a hydraulic clutch. The car does have several interesting modifications and upgrades as well as a very interesting and colorful past.

Wilwood is a high quality disc brake aftermarket manufacturer. If you are going to convert to disc brakes, they make excellent kits. This is a personal decision and my opinion is just that. I prefer the stock arrangements whenever possible. Yes, the drum brakes do not stop as well as disc brakes, but unless you use your Thunderbird as a daily commuter, I see no reason for the upgrade. I have 8 vintage cars from 1931 to 1968. I try to keep them as stock as possible, If I want a car that drives like a new car, I would buy a new car and not try to make an old car drive like a new car. The brakes on my Model A AA truck are barely passable. Since I know that they don't stop like new cars, I leave lots of extra space between me and the car in front. The fun of driving an old car, for me, is driving it like it is an old car. Drive a little slower, be more cautious and enjoy a slower pace.

I also think that everyone who owns a car has the right to do with it whatever they want. Don't take my opinion as your guide unless you feel the same. If you want Wilwood disc brakes, Borgenson power steering, an LS motor, or Jaguar independent rear suspension, then you should make yourself happy and make those modifications.

 

[gmsnowball]

Thanks and I agree. I also own several old cars all with stock brakes the oldest being a 41 Chevy coupe. I like driving older cars and I too allow for extra space between cars but that doesn’t stop the idiots who pull in front of you. I am taking the master cylinder out today to see what arrangements I can make to keep it. The brake drums and shoes look like new but because they have been setting for over 30 years I will try to hone and rebuild the wheel cylinders and possibly the master cylinder and slave cylinder for the clutch if rebuild kits exist. I will use all new hardware. I always have liked working in old cars and look at it as a challenge to make them operate as they were when they were new. I learn more about this car every time I look at it. Can’t wait to get it back in the road.

 

[gmsnowball]

That master cylinder appears to be from a 1960 or so International Scout or Travelall and is intended as a combination brake and clutch unit. I have no idea why someone would do that, but I suspect that the firewall was cut and modified for the installation. Is this a standard transmission car? It is not a dual master cylinder as in it does not have a separate compartment for the front and rear brakes.

actually the master cylinder is from. 60-66 GMC C 20 truck. It has three mounting holes and the International has four. That’s the only difference.

 

[BillM]

If you want to keep the car original might look into having someone like A-1 Cardone doing an R&R on it. You should have a store near you who has access to them.

 

[gmsnowball]

I found several suppliers. They are still making new and rebuilt master cylinders.

 

[biddle]

I found several suppliers. They are still making new and rebuilt master cylinders.

Some of the supplier's names would definitely be helpful.

 

[cokefirst]

Mac's has the master cylinder. $89

 

[gmsnowball]

Some of the supplier's names would definitely be helpful.

Suppliers are for the hydraulic master cylinder from the GMC C20 truck the previous owner installed on my T Bird some 30 or so years ago. Haven’t decided wether to go back original on the clutch or keep the hydraulic clutch/brake Master cylinder, someone put a lot of effort, cost and ingenuity in this build. I will be glad to share all my sources.