Technical What dual M/cylinder to replace 39-48 Ford item.

I need to upgrade my single acting master cylinder with a dual circuit item, so what one would suit my 48 Ford brakes. This is for my RPU.
Cheers, JW

 

You'll need an adapter, but chassis engineering makes one. I used a late 60's mustang drum-drum manual master cylinder. A manual MC should have residual valves built into it. The only issue is that the fittings exit on the frame side, which is tight, but I believe an AMC mc of the same years has the fittings on the opposite side. I didn't know that until after I finished the brakes.

EDIT: I guess I assumed you are using Ford pedals? That's what the adapter is for, to adapt a modern 2 bolt MC to the old Ford pedals with 3 bolts.

 

Thanks, there is some room for the lines and i can make any adapter needed. JW

 

mate since your in NZ get one of a hq holden with drum brakes the type that has the big nut on the end ,take the nut of drill for 1/8 gas and your early ford brake switch screws back in looks all stock and works ,simple little adapter to mount it to the pedal assy ,believe me it works well

 

Will look into that, but HQ's have disc brake front brakes.
If I went with the Mustang cylinder what exact year or part number should I be looking for as im sure they are not in many parts houses in NZ. JW

 

Most of the mustang masters I see used are labeled first gen so 64-66 ish?

 

Thanks for that. JW

 

Take a look at the adapters online. Most the ones I see look extremely simple if I was looking at overseas shipping time I'd be leaning towards making one if it were an option.

 

The first Mustangs to use dual masters were '67, when they were US mandated.

 

I had a '64 Mustang MC in the roadster and replaced it with a '67 dual MC. CJ Pony makes a slick kit with the fittings and it takes about an hour to make the switch.

 

Thanks for the help guys, did the 67 have drums all round, just thinking of the residual line valves.
On our NZ auction site there is a new 67-73 dual unit for NZ$200. JW

 

They still sell them at auto parts stores here like Napa, orielys etc. you might want to check your stores for the equivalent?

 

'67 Mustangs could be either all drum or disc/drum, depending on model and equipment.

The main difference between drum/drum vs disc/drum is the drum/drum has a residual valve in the MC for both frt & rr and the the disc/drum MC has only for rear. The addition of an inline residual pressure valve for the frt can correct that.

I used such a system on a '47 Ford I built several years ago.

Ray

 

I went to our parts store yesterday to see about a 64-66 cylinder and no listing, that's before I found out they are a single system unit. will try tomorrow for a 67.
I was a mechanic up to 30 years ago so adaption wont be an issue, but I would like the cylinder to have both valves in it.
Cheers, JW

 

this is what you need.67 mustang as others have said.
Bought off t/m brand new and loaned to another mate to use in his model a with 48 brakes alround. Worked well so he bought his own new. Can find out where he bought it if you have trouble finding one

 

A 70ish AMC is pretty much identical to the early mustang but the lines come out the opposite side. I'm gonna use one on my coupe so the lines point towards the frame rail instead of the center of the car.

 

I'm using a jeep/amc master on my '28 (early/mid 70's opposite side ports), I've used drum/drum mustang masters ('67 and up) and I used a late 60's Chrysler master on my '47 (short for under floor space). All I made my own adapters.

 

Nice job, good look on the adapter also

 

Late Mark 2 Cortina's have the adaptor as OEM made from stamped steel
Early Cortinas all had Single master cylinder vertical bolt pattern and Dual M/C's were horizontal

 

Thanks again for your help guys. Mark, that is what I will go with. I see it has two different line sizes.
Kerry, I think it would be a hard job finding a late MKII Cortina now days. I made the mount for the 39-48 cylinder that's there now so I will just modify/adapt that.
There are a lot of Mustangs in NZ now so that would be the easiest to find.
Im going to the States in August so I may get one then, Mrs W is also buying a Mustang for herself while there, isn't that ironic JW

 

you NZ people must of been not trusted with drum brakes ,in Australia lots of hq holdens had drum brakes ,I only suggested this idea because my 35 has been running this set up for twenty years up till that time it still had rod brakes

 

My bet is its because of our hilly terrain. I have never seen a HQ Holden with drums up front. These are Australian made cars for our State side friends. JW

 

We have used Mitsubishi L300 hi top van master cylinders a couple of times in builds feeding f100 drums. I think these are only 15/16 bore. They work real well, also the reservoir can be mounted remotely , what we have done in the past is put the reservoir under the seat just poking through the floor to gain a little height over the master.

 

Thanks Brian, I have just ordered a 67 drum-drum dual circuit master with two residual line valves..........was told it was the only one they could find in NZ!! NZ$251 including our 15% tax.
I wanted to have an imperial cylinder as the only thing that is metric on the car is the alternator, and that bugs me a bit.
Thanks for all the help guys. JW

 

Yup I know what you are saying. I have a small metric container in the far corner of the shed, some things still seem to get in to pollute the imperial purity. Dang off shore junk.
How come you need ( I presume 10lb) residual valves with a drum drum master. Not that I know fully understand the system other than drums need a 10lb residual and discs a 2lb.

 

It keeps tension on the wheel cylinder cups, if you have the same on discs they will drag. JW

 

Your Mustang drum/drum MC may very well have residual pressure valves already in place internally. Aside from bore size, the main difference in disc or drum MC's is the inclusion, or absence of, RPV's.

On old style single circuit MC's, the RPV was incorporated in the MC piston and cup assembly. Some units use an small spring and check ball type in the MC outlet ports.

Ray

 

Spot on, Ray. JW

 

Make sure you bench bleed it properly . that was the only problem my mate had - he didn't do it the first time and the second time he didn't do it properly so had a lot of issues !

 

A good reminder, cheers.

If anyone else has had good results with another dual master cylinder with 39-48 Ford brakes please post up your comb as it my help others. JW