Master cylinder conversion
 

Guys-

I am in the process of converting a '36 to hydraulic brakes. I have been using floaters on the brakes for some time but it seems like they have a constant demand for being adjusted which is no long "fun."

While searching the archives I came across an excellent response to a question that "Mart" made in regards to a dual chamber m/c set-up:

"If a supplier were to arrange a 1-1/16" dual cylinder with built in residual valves, nice easy to access reservoir and a three bolt fixing like the original, then kit it out with outlets so a 1/4 pipe would screw straight in, plus a port for the brake light switch then they would sell like hot cakes to the early ford squad." (7-28-14)

Anyone ever find something close or possibly a "workable" 1-1/16" m/c like Mart suggested?

Thanks

Tom

Re: Master cylinder conversion
 

I'm not sure you can find a dual MC with the 1 1/16 bore. They do make an adapter that goes from 3 bolt to 2 bolt for the 39 pedal assemble ,so you can use the dual MC. It moves the MC back about 3/4". There are adapters that will screw into the MC that will allow the 1/4" lines. Some dual cylinders have residual valves and some do not. It would take some research and a parts house with some knowledgeable people willing to help to find a cylinder with the correct specifications to use with the adapter.

Re: Master cylinder conversion
 

Hi all; I ran across a old Ford with a dual master cyl and the big 5/16' tubing ports. It was a drum/drum early '60s Cadillac. We found a new/ rebuilt one in the NAPA catalog, and it all worked great. Newc

Re: Master cylinder conversion
 

Newc - like this one? 1962-66 Cadillac Master Cylinder

http://www.rockauto.com/catalog/more...564&cc=1320297

https://www.opgi.com/cadillac/CE10703/

http://www.summitracing.com/parts/dh.../make/cadillac

Re: Master cylinder conversion
 

Tom,
I recently went through this. The only 1 1/16" mc I found was from Wilwood. Unfortunately, it just didn't move enough fluid to work correctly and I ended up using a 1 1/8" one from Summit.

When I say 'correctly', I spent a lot of time studying how a mc works and what is SUPPOSED to happen if one circuit fails. So, while the 1 1/6" mc worked OK under normal circumstances, it would NOT work in the event of a failure of either front or rear brakes. There was just not enough pedal travel in my '36.

IMO, I think the 1 1/8" one works great. The pedal effort/travel is fine for me.

But Mart is correct. Plumbing is a nightmare all to itself. I spent a lot of time on the Net and at the local parts houses trying to get all the fittings I needed. It was not fun.

Heard

Re: Master cylinder conversion
 

Drum/drum Mustang works for me. It's not an easy 10 second swap, and requires some adapters for the 1/4" lines, but it works very well.

Re: Master cylinder conversion
 

HEY TOM: Your going the wrong way ... the bigger bore MC. "softer peddle" and much less pressure at the wheel cylinder and "not better stopping" .:confused:..I assume not what you want ?? ..so you need to move more fluid ?? need to adjust the breaks CLOSER to the drum ?? .... some years ago I went through this with a VW dunn buggie, much bigger engine and tires and class body... could not stop it, running hard out in the sand.:mad:... was told by the big engine builders to go to a smaller MC.... use one off a VW transpotter ?? it was smaller buy ?? MM ?? and boy did it work.;)...I could lock up big tires on the street ?? woo hoo , could not believe it.
So when you get it all built ie " smaller MC. adapter plate, and pluming fittings made " please send all info with drawings in detail, and all parts numbers..ect...... thanks ..........OLD...........BILL:cool:

Re: Master cylinder conversion
 

Plus 1 for Mustang MC. Drum Drum and built in residual pressure valves.

http://www.summitracing.com/parts/DH...n/?prefilter=1

Re: Master cylinder conversion
 

John-

Thanks for the reply. Looking over the Summit web site you referred to brings up a question. The ports appear to be on what would be the inboard side. Is there a model that has the posts on the other side? If not, how did you hook-up the brake tubing? In my situation the brake lines will be on the outboard side (frame side) of the car.

Again, thanks for the quick reply.

Tom

Re: Master cylinder conversion
 

I used the Mustang Drum Drum on 2 of my projects, my 30Model coupe and my dragster, just make sure the leverage linkage that moves the rod to MC is short, If you have to long a linkage you'll have to push the pedal harder. Walt

Re: Master cylinder conversion
 

Just loop them over or under the MC.
(not my car, just some random pictures)

Re: Master cylinder conversion
 

Use a 1967 Mustang cyl. drum drum.

Re: Master cylinder conversion
 

That's what I use, the 67 Mustang. Need to watch, they come both drum/drum and disc/drum.

Re: Master cylinder conversion
 

There are a couple of problems with the first picture. One, the lines should be always be routed out of harms way, and in this case either along side (even with) the master or at least as close as possible running under. Second, there looks to be copious amounts of Teflon sealer or tape :rolleyes:, both totally unnecessary or needed with the inverted flare fittings shown. This is one case of how not to plumb a master cylinder. :(

Re: Master cylinder conversion
 

Good catch! Just a photo I grabbed quickly, should have looked it over better!!! Anyway, forgetting the photo, you can run the lines around or under the MC.

Using tape or sealant on brake lines is a big No, No. The flare should do the sealing and if it doesn't then it needs to be corrected.

Again, Good catch V8 Bob.

Re: Master cylinder conversion
 

Tom, I don't think they make Mustang cylinders with ports on oposite side. You can route to other side as mentioned. Also the front brakes are connected to the port nearest the pushrod. The ports have different sizes. I went to autozone and got inverted flare fittings to fit each hole for 1/4 inch line.

I used MT Car Bendix brakes on the front and Ford brakes on the rear.

Re: Master cylinder conversion
 

10-1373 is a 1" bore drum/drum master similar to the Mustang; but with the ports on the opposite side.

Should use 1/4" lines too; not the 3/16" lines that are in the picture.

Re: Master cylinder conversion
 

Why would you want to use 1/4" lines?

Re: Master cylinder conversion
 

Good info rich! The only thing to possibly be careful of with a 1" bore in this case is the fact that it's going to require a longer pedal stroke to displace an equal volume of fluid as that displaced by a 1-1/16" bore, especially if one side of the cylinder ever fails. That can be a problem with the pedal geometry in these old Fords. Just sayin'! DD

Re: Master cylinder conversion
 

I just helped a friend change out the brakes and master cylinder on his 45 pickup. He now has F-100 brakes all around. We used a 1" bore dual cylinder. I hope it will work. He is installing the fronts today.

Re: Master cylinder conversion
 

I fully understand what your saying here.
I fitted a 1" dual master on my truck, this being the mustang size that's ment to be the ticket. Pedal travel was to much for my liking. When fiddling with it I cracked open the union to the rear brakes to see what would happen in a leak on one circuit situation, well the pedal went almost to the floor! Not good, has any one else tried this? It appeared to me that as I thought, that mustang one is to Small. And if they all travel this far some cars are basically gonna be left with no brakes when one circuit leaks. I say some as a lot of hotrods don't have the same amount of travel available on the pedal.
What's on mine now? A stock Ford single master, bolts in easy, plumbs easy, bleeds easy, looks right has the correct size bore, pedal travel is like I like them, about 1 1/2". If it fails, the hand brake (e brake) is spot on and works great. Better than rely on some thing that won't actually work when you most need it.
Martin.

Re: Master cylinder conversion
 

scooder ........This is exactly the situation I was alluding-to in my previous post. This CAUTION is only meant for the folks that may not understand how a dual master cylinder actually works when one side of it "goes south". DD

Re: Master cylinder conversion
 

I tried a stock early Ford single master cylinder. It was 1 1/8 or 1/16. The pedal required too much force. When I went to 1" the brakes responded much better. This was in a model A and the pedal arm ratio may be different on other cars. I have not tried a simulated failure of one circuit. That is really a good idea.

Richard Lacy uses 15/16" in his kits.

John

Re: Master cylinder conversion
 

I changed the master cylinder on my roadster from a mustang 1" unit to a 70's E250 ford van 1-1/16" unit. The pedal is nice and firm now and right in it's "sweet spot". Before the pedal was too far down. The The van unit is substantially bigger though. I just took the view that original ford master cylinders were 1-1/16" so the replacement cylinder should be the same diameter.

Re: Master cylinder conversion
 

Mart, you may be ok with the E250 m/c if you have plenty of available pedal travel. It really did shock me how much extra "nothing" there was when I cracked off the back circuit.
I'm sure that in a very high amount of master cylinder convertions to twin circuit master cylinders, the extra plumbing, adapting and such is just a complete waste of time, money and effort. As in a circuit failure, the pedal will hit the floor before anything happens!
Not directed at you Mart, as I know how you think, your not a bubble pack kit form type of bloke.
the belief that as something is available in a kit, or in a glossy magazine or because that's what so and so sells, does not make it right! Stuff is sold purely because people will buy it, that's it.
Rich done his home work and studied what's going on and made an informed (well researched) choice. He is correct.
Double D also knows this.
I actually tested it.
Make um safe.
Martin.

Re: Master cylinder conversion
 

I had kinda the same experience on my '47, with the 1" bore Mustang cylinder I had lower than optimum pedal applied position and if you opened one side, it would go all but on the floor before applying the other. This did not seem like a comfortable set-up; so I picked up one of the E-250 masters that Mart mentioned. First thing I found was that this master has a longer stroke; but I thought I would play with it a little so I made a pedal pad extension so it didn't go below the floor and bled the system. The pedal apply position ended up to where it should be and when I opened either side of the system, I was surprised to find the pedal remained a reasonable distance above the floor. Have to see how this works when the car gets on the road.

I also put one of the E-250 masters on the '35 chassis I'm building; don't have the body on, so it will be interesting to see how the pedal travel works out.

I think there are quite few people with dual master set-ups that could be in for a rude awakening some day (especially the ones who don't feel it is necessary to include an operational e-brake in their build).

Re: Master cylinder conversion
 

While the application pressure ends up equal with either size lines, the 1/4" lines flow more during application and release. Not so fussy with discs; but more so with drums.

Look how they plumbed production cars before they went to diagonal split
or four disc set-ups. 1/4" main lines feeding into 3/16" branches.

Early Ford Lockheeds really like 1/4" all the way just the way Henry built them.

Re: Master cylinder conversion
 

One way to tune the master cylinder is to insert a washer behind the clip holding the piston in the bore. The thickness wants to be gauged so the recuperation port just about remains uncovered. By minimising the travel before the piston gets to the other side of the port means the pressure starts building higher in the pedal travel. Also the pedal free play wants to be at the minimum for the same reason. Caution is required though, because too thick a washer or no free play will stop the recuperation port from working and make the brakes stick on when things warm up.

Mart.

Re: Master cylinder conversion
 

A bit of advice re ports. Napa carry the eaton weatherhead line of adaptors and the more common dual cylinders have typically a 1/" 20 port and a 9/16" 20 port. Adaptors are available to get these both down to accept a 1/4" inverted flare fitting (standard early ford fare.

Do not use the alternative method of using an oversize flare nut that puts the 1/4" pipe straight into the port. I have only ever had one brake line failure and it was in the dual MC with one of these oversize nuts. Luckily I sensed the pedal lowering as I used the brakes and limped the car home at low speed. I could see fluid dripping from the union. I reworked it with the proper weatherhead adaptor and a new pipe and all was well.

The adaptors are available for 3/16" pipe too. I have the numbers somewhere if I can find them I will post them.

I do agree with my good friend Martin (Scooder) 9 times out of 10 the dual cylinder will offer no effectual advantage. I have never tested my system to see if one circuit would still work if one end or the other went out.

I have a single circuit cylinder in my 33 and have no burning desire to swap it out. Having the dual cylinder in no way should be an excuse to keep the brakes in anything other than tip top condition.

Mart.

Re: Master cylinder conversion
 

This is a very good thread with several issues I have not thought about. I still have to do all the brake installation on my AV8 and will use this information.

Thanks,John

Re: Master cylinder conversion
 

I've done two brake systems over the past few years. Have done many hydrolic conversions in the past. I came to the conclusion that just adding a hydrolic cylinder doesn't improve the braking of the car. Using the 39-48 system doesn't improve the braking of the vehicle, it only makes it easier to push on the pedal. Many guys will tell you the old rod/cable systems worked just as well, when in good condition. With hi-way speeds of today you should consider up grading to disks in the front and save the old systems for parades.

Re: Master cylinder conversion
 

Dual master cylinder discussions come up often, and usually with some confusion and/or lack of understanding of how or why they work; kind of troubling as they have been available since at least 1962, and USA mandated in '67 :(

There are three basic items that have to be taken into account when installing a dual master on a non-stock/custom application; bore size, M/C stroke length and pedal ratio. The M/C has to be able to be fully stroked before the pedal runs out of travel, period. If total stroke cannot be attained, the safety function of a dual M/C may not be available in the event of a system failure. The brakes also have to be assembled, adjusted (if applicable) properly and in good condition.

I know for a fact dual masters work as designed, as I spent most of my working life dynamically testing dual brake systems, and they will work 10 out of 10 times if set up properly. (Sorry Mart) Much better to have a partial loss of pedal and one axle braking, v.s. NO brakes in the event of a line/cup/seal failure. No amount of maintenance can insure a hydraulic failure will never occur. :)

Re: Master cylinder conversion
 

Agree with everything you say Bob, They will work properly 10 out of 10 times if set up correctly. The point I was trying to make is that when retrofitting to an early ford or a previously mechanically braked setup converted to hydraulic they are probably not setup properly. An OEM car maker will design the pedal/cylinder/rest of system to make sure the required travel is available. That may mean making sure plenty of spare pedal travel is available beyond the normally used travel. More easily accommodated when starting with a clean sheet of paper design.

A modified early ford setup hasn't had that extra travel designed in and that was why I made the statement.

I hope I'm wrong and if someone should suffer a partial failure they do manage to come to a stop safely. But unfortunately I was sort of agreeing with a previous point that people may believe they have increased the safety level of their vehicle but in reality that belief may be unfounded.

Mart.

Re: Master cylinder conversion
 

This is why in the end I kept the single circuit original setup. In saying that I have a new USA made m/c all new lines I made, new wheel/ cyls too. And have just recently added a VH 44 power booster, It works well.

Re: Master cylinder conversion
 

Mart, I am using a 1" bore disc/drum Mustang M/C on two vehicles; a '51 with stock pedals, and on my '32 with '33/'34 pedals; also a 1" F-250 disc/drum M/C on my '40, and all three masters will bottom out before the pedals, so I know it's possible with old Ford pedals. The pedal has to return fully with it's own spring, along with minimum push rod clearance of about 1/16", and careful use of carpet padding to enable full stroke.
Confirming a full stroke is possible, then bleeding one axle at a time and checking brake operation (as mentioned earlier) will ensure the safety advantage of a dual braking system. :)

Re: Master cylinder conversion
 

If carefull carpeting makes a difference, your getting damn close to the floor! That's to close for me, add a smidge of unadjusted wear, little bit of fade, it's at the floor!
Why not fit a bigger bore master cylinder and have some much needed comfort room? Surely you can understand this would be better and safer?
Martin.

Re: Master cylinder conversion
 

It's called compromise. There are several factors that have to be weighed when designing an apply system, and among them are comfort, seating location, pedal efforts and M/C operation.
Close to the floor is fine as long as you can fully stroke the master. Wear and fade won't change the total stroke available, as many OE vehicle's pedals will also be "close" to the floor during a full stroke check. Floor carpet doesn't have to be 1" thick to be comfortable, especially around the pedals.
Going to a larger M/C bore will increase pedal effort, without ratio change, and has to be considered. Keeping a manual system around 50 lbs. or less pedal force for most braking is a good target.
A few vehicles will allow a long brake pedal to stop well above the floor without looking or being awkward, but most will not.

Re: Master cylinder conversion
 

[QUOTE=V8 Bob;1013445]It's called compromise. There are several factors that have to be weighed when designing an apply system, and among them are comfort, seating location, pedal efforts and M/C operation.
Close to the floor is fine as long as you can fully stroke the master. Wear and fade won't change the total stroke available........ QUOTE]

Everything V8 Bob states above is gospel. The most-IMPORTANT part of the statement is a TOTAL and clear understanding of what the term fully stroke the master means. As Bob says, if your installation is not capable of "fully stroking the master" BEFORE the pedal mechanically runs-out of travel, the DUAL-master-implied redundancy will not be possible if pressure is lost on one circuit in the dual system. DD

Re: Master cylinder conversion
 

V8 Bob, did you have clearance problems with the F250 MC in your 40? I used a 69 mustang in mine and had to cut the cover and weld flat. Otherwise is too tight to the floor and cannot remove the lid/cover.
Other than that the brakes work fine and have disc/drums.

Re: Master cylinder conversion
 

Bob, sorry missed the bloody obvious full stroke.I'm not nit picking here, I'm just making sure we have the hole picture.
If the master cylinder bore is to small, is it possible that it will work "fine" with both circuits operating as they should, but in a one circuit fail, the master cylinder can't displace enough fluid to operate the one circuit now doing all the work. Irrespective of the ability to full stroke?
I'm still uncomfortable with using a smaller bore master cylinder than the original one, all else being equal.
I get your compromise bit, and I spose it's what your used to. I only drive old stuff, and work on old stuff. I'm used to brakes that you have to stand on, and I'm comfortable with this. When I have the misfortune to drive something "new" (read built from 1980's on) I'm shocked at the brake sensitivity. Read kiss the windscreen.
So pedal pressure isn't really a "given" what's ideal to some is unacceptable to others.
What say you.
Thanks
Martin.