What Master Cylinder
 

I am putting '40 Ford Lockheed style brakes on my Model A. I am using a Vacuum type booster. Here's my question: what dual reservoir master cylinder would I want to use? It's my understanding that the original cylinder bore was 1 1/16" bore, Is that correct? The front and rear wheel cylinders are different bore sizes so how would that work with a dual Master? To top it off I am going to need to use a remote reservoir, Would that require a special master or would you just add a remote reservoir to a regular type master. Thanks!

Re: What Master Cylinder
 

If using a DUAL M/C that has the same bore on BOTH ends of the cylinder, you will effectively be reproducing the results found using the stock, single bore M/C. You noted that the front and rear WHEEL CYLINDERS for the '40 brakes have differing diameters. There are a couple of reasons for this. One reason being that the REAR brakes are responsible for LESS braking than the FRONT brakes are. A couple of factors figure into this, like the front axle of many cars bear more weight than the rear axle, possibly ~60/40 for instance....YOUR RESULTS MAY VARY!

Additionally, when the brakes are applied, especially in taller vehicles like these old Fords tend to be, weight transfer takes place effectively transferring more weight from the rear braking load toward the front brakes' braking load. This amounts to the REAR brakes requiring LESS pressure than the FRONTS, to help refrain from locking-up the REARS with less weight on them. Meanwhile, the FRONTS with a higher percentage of weight on them are working as hard as they possibly can in the attempt to pressurize (slow) the drum BEFORE lock-up.

Remember, a tire that is locked-up and skidding is not producing anything near the stopping power of a tire that is just shy of breaking-loose. For that reason, and taking into account ALL of the above, there is an awful lot of serious engineering that goes into the sizing of wheel cylinder and master cylinder combinations.

Getting back to the rear wheel cylinders being smaller than the fronts. Considering using a M/C with a constant bore for both fronts and rears, an INCREASE in WHEEL cylinder bore to a LARGER DIAMETER will produce MORE pressure at the wheel cylinder/brake shoes. Inversely, DECREASING wheel cylinder bore to a SMALLER DIAMETER will DECREASE pressure at wheel cylinder/brake shoes. Alternatively, changing the M/C bores in relation to wheel cylinder bores will also change effective pressures.

Undoubtedly, most of us mere mortals don't have the credentials nor the facilities to properly engineer a braking system to the fullest. But there are tried & true combinations that guys like us have swapped and used for decades that work efficiently when using quality parts. Lockheed hydraulic brakes on an 'A'-bone is certainly not a new idea. A lot of guys running that combination wanting to employ a dual M/C tend to use a '67-'73-ish Mustang M/C designed for DRUM/DRUM brakes.

One more thing to remember....ALWAYS test that your brake pedal STROKE has enough room for a FULL stroke WHEN ONE SIDE OF YOUR SYSTEM is OPEN. It takes a LONGER STROKE than normal when one side of your system has a leak in it. You can see WHY if you carefully study the system BELOW!

Coop


https://www.fordbarn.com/forum/attac...6&d=1444500407

Re: What Master Cylinder
 

I don't know anything about this product but you might contact these guys:


https://www.millworkshotrod.com/prod...=7263515082797
Early Ford Dual Master Cylinder AV8 Adapter Kits 1939-1941 Ford Passenger and Light Truck, 1946-1952 Pick Up
This kit allows you to run a dual master cylinder on both 1939-1941 Ford car and light truck pedal assemblies as well as 1946-1952 Ford pick-up pedal assemblies using the stock push rod and boot. The kit includes a Made in the USA adapter and hardware, upsized brake fittings as well as a brand new dual master cylinder (not remanufactured). Perfect for your AV8 conversion.

Re: What Master Cylinder
 

For over 25 years on all my drum/drum chassis builds I have used a Cardone 1329 which exits toward the frame or a Cardone 1292 which exits toward the trans. I have used these master cylinders with early Ford brakes, Mt Lincoln brakes and a combination of the early style Ford or Lincoln brakes and late Ford 11X2.25 drum brakes. These master cylinders do not require external check valves as they are built into the cylinders.

Re: What Master Cylinder
 

Krylon's recommendation for a Cardone 1329 is a good dual bowl cylinder with bore sizes very close to stock Ford's 1 -1/16". It also has good port sizes that can be used and adapted to 1/4" brake lines.


Bore Diameter: 1" (25.4 mm)
Master Cylinder Primary Port Size: 9/16 x 18
Master Cylinder Secondary Port Size: 1/2 x 20 more details on - https://www.carid.com/cardone/brake-...n-13-1329.html


I currently have a stepped bore master in my 32. The stepped bore was designed for moving a large volume of fluid quickly to take up the gap in early Chevy applications that used front disks that were low drag. These are the bore sizes on my CARDONE 101905. Note that there are no residual check valves inside this MS so those shall be added into your system.


Bore Diameter (N) 0.945"

Bore Diameter (N-1) 1.25"


For the front brakes, primary side, the initial lower pressure fluid is pushed with the N-1 large bore of 1.25". This closes the gap between front shoes and brake drum, then the N bore of 0.945" applies high pressure to both the front and rear brake drums. The advantage is that the initial 1/4" stroke takes up the gap and then the smaller N bore takes over. The pedal stay6s high without a lot of pedal travel. I'm very happy with this setup but I also believe that Krylon's MS is a great choice too.

Re: What Master Cylinder
 

I've used the 73/74 Ford f100 MS. It's the first year Ford had disk brakes without power assist. I'll admit you have to push alittle harder, but it works pretty good on my 47 KB-1 int. been over 30 years.
GrampPS It's for sale.

Re: What Master Cylinder
 

Hey Glenn.....This is an interesting piece for me, as I had never heard of this "stepped-bore" cylinder design. If I am fully understanding the concept, one of these type M/Cs sounds like it would preclude the pedal from running out of stroke because of the initial "quick-fill" feature. Then, once the shoes have contacted the drums and initial system pressure begins to increase, the SMALLER DIAMETER than usual M/C bore should ultimately cause higher pressures to develop against the shoes, WITHOUT the increased foot pressure on the pedal. Kind'a like killin' both birds with one rock! Am I understanding this correctly, or am I full of it again? Appreciate you posting this info, Glenn! Coop


https://www.fordbarn.com/forum/attac...9&d=1657714430

Re: What Master Cylinder
 

Yes Coop you got the concept down correctly!

I remember years ago a product by Mico that is similar in concept so after extensive net searching a couple of years ago I found this MC. There is also another one that has an even larger diameter but it was designed for power brakes. I have a scan of the magazine article reviewing the Mico that I could dig out if you're interested.

https://www.mico.com/products/brake-...ster-cylinders

Re: What Master Cylinder
 

Glenn....I appreciate the offer on the magazine article, but not necessary, as you've already done enough to get my wheels turning.

It seems to me that a lot of folks considering upgrading to a DUAL M/C do not realize that when one circuit in a dual M/C becomes compromised, that the stroke of the internal pistons and springs WILL have to increase beyond normal stroke length to create pressure in the circuit that is not compromised. As such, folks MUST TEST their modified systems to assure that there is enough room available in their car to assure enough pedal stroke available IF either circuit becomes compromised. That is why I like to keep posting the drawing BELOW, as studying it shows clearly WHY the stroke must increase beyond normal to produce AVAILABLE stopping pressure.


https://www.fordbarn.com/forum/attac...6&d=1444500407


I believe wholeheartedly that the virtues of this "stepped-bore" design needs to be passed-along to anyone contemplating a M/C change or upgrade. Thanks again!

Coop

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Re: What Master Cylinder
 

I have had personal experience with this. Because of rust issues with the steel lines, I have lost the brakes on my "beater" 1999 Ford F150 twice. The first time, I lost a rear line, but I still had enough brakes to get it to my shop to replace it. Before I even had a chance to get to the rest of the lines, I lost a front line. This time, I had virtually no brakes at all, and crept back to my shop 2 miles at 5 mph on the shoulder of a country road. After replacing the rest of the lines and bleeding the brakes, the brakes were perfect again.

Now this was factory designed dual system; in my opinion, a home-designed system without extensive planning and execution would be even worse.

Re: What Master Cylinder
 

CoopMan, I appreciate the input and will take that in to consideration when working out the details of my install. Thanks!

Re: What Master Cylinder
 

Anybody care to explain:
"Considering using a M/C with a constant bore for both fronts and rears, an INCREASE in WHEEL cylinder bore to a LARGER DIAMETER will produce LESS pressure at the wheel cylinder/brake shoes. Inversely, DECREASING wheel cylinder bore to a SMALLER DIAMETER will INCREASE pressure at wheel cylinder/brake shoes."
All my hydraulic experiences in the last 40 years are the opposite.

Re: What Master Cylinder
 

'28 RPU ....I appreciate your comment!

Ya know, if I were you, I believe I'd be very tempted to go with that "CARDONE 101905" M/C that "glennpm" is using. Go back and study POSTS #5, 7 and 8 above. Glenn is a sharp guy, and has a reputation for posting accurate and trustworthy information. I believe it would be reasonable to assume that the weights of his roadster and your RPU wouldn't be too far apart. This sounds like the best "NEW TECHNOLOGY" that I have heard about in a long time.

Coop

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Re: What Master Cylinder
 

vincent....YOU are absolutely CORRECT!!! I worded all of that VERY POORLY, and I had a very uneasy feeling that I had worded it backwards when I was pounding that out. Nevertheless, I BLEW IT, and I really thank you for bringing it to my attention. I'm sorry for any heartache that I may have caused here, and I'm gonna go back and attempt to fix it all. The Coopman

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Re: What Master Cylinder
 

Thanks Coop!

Re: What Master Cylinder
 

Thanks Coop for the accolades!


Glenn

Re: What Master Cylinder
 

After all, you are not completely backwards as a more powerful wheel cylinder, which does not travel enough distance to put all his pressure on the brake shoe, is indeed less efficient. So the fine line to balance on is: get the maximum leverage from foot pedal to MC, then a good ratio from MC to WC and finally make sure that your WCs travel far enough to put full pressure on the shoes. You could always add adjustable WCs to the backing plate to keep the brake shoes in close proximity to the drum or manufacture your own adjustable brake shoe stops to achieve the same goal. Thus the pulling springs will not pull the shoes (and the WC) too far away from the drum. This will give you minimal clearance between shoe and drum and thus the WC can put all his pressure on the shoe when the pedal is pushed down.

Re: What Master Cylinder
 

I am not familiar with adjustable wheel cylinders and would like to hear about them.

Re: What Master Cylinder
 

I will have to call Mico, their product looks very interesting but they have way too many products for me to figure it out on their website. Can it work with a booster? Is it available in a 2 circuit (front brake/ rear brake separate) configuration?

Re: What Master Cylinder
 

Glenn, can the Cardone 101905 work with a booster?

Re: What Master Cylinder
 

I'm not trying to answer for Glenn, but I see no reason that it cannot be used with a booster, as it has a standard 2-hole mounting flange.


https://www.fordbarn.com/forum/attac...9&d=1657867355

To be quite honest with you, that Model 'A' of yours is such a relatively light car to begin with, and combined with the design of the Bendix-type brakes, I doubt seriously that you will need (or even want) a booster. Coop


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Re: What Master Cylinder
 

Here is a pic of an adjustable WC. This is only adjustable on one side (use with floating shoes) but you can get them adjustable on both sides which will allow you to adjust for minimum play on fixed brake shoes (non Bendix type).

Re: What Master Cylinder
 

Yes there is another stepped bore MC that used a booster:


CARDONE 101923
Bore Diameter (N) 24mm or 0.945"
Bore Diameter (N-1) 36mm or 1.417"

Re: What Master Cylinder
 

Hey guys, I really appreciate the help! Coop, they are '40 Ford Lockheed brakes not Bendix. I want to use a booster because I promised her that I would make it so that she could drive it (actually I had to agree to that or I wasn't going to be able to buy it (and stay married). She drives a '06 Mustang GT with 4 wheel disc brakes that will throw you through the windshield and when it comes to putting on the brakes on the A if they aren't somewhat similar she will have problems. I hope that helps y'all understand where I'm going with this. Ultimately I hope to go to 4 wheel discs on the A (more because I want to that because I need to).

Re: What Master Cylinder
 

If I had initially read your first post a little more thoroughly, you were clear as day about using the Lockheed brakes.

As far as the 4-wheel DISCS go, I understand about "CUZ I WANT TO". But you're going to have (potentially) way more brakes than you'll be able to use on that light car (IF you ever get the four discs all tuned and working happily together). If you left the Lockheeds on the rear, and bolted NEW "Bendix" Lincoln drum brakes on the front, with booster, I'd about guarantee that 4 wheel discs WOULDN'T stop you any faster (shorter). Never forget that even the best braking is only as good as tires that don't slide (lock-up).

This has been fun. Keep us abreast of progress. Coop

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Re: What Master Cylinder
 

Glenn, will the 101923 work ok with my drum/drum set up? I know that I will have to use residual valves and I also plan to use a proportioning valve. Would it work with the disc/disc set up I'm planning for the future? Thanks to everybody for their help!

Re: What Master Cylinder
 

Hi!

Yes the power brake version, #101923, would work with the drum/drum setup you're planning to use. Do you have space for the boosted brake MC?

This MC has no residual pressure check valves within it. For drum/drum you would need a 10psi check valve in both the front brake and rear brake circuits.

If you decided later to add discs to the front and keep the current rear drums, it would work as long as you have disc calipers that are the same or very close to those used on an 1986 Chevy S10 Blazer, the original application for this MC. In this case you would need to remove the 10psi residual check valve from the front brakes and either add a 2psi valve or use the stock Chevy metering valve and also remove both the front and rear check valves. See attached article.

The article says, "The proportioning section controls the outlet pressure to the rear brakes after a predetermined rear input pressure has been reached; this feature is provided for vehicles with light loads, to help prevent rear wheel lock-up. The by-pass feature of this valve assures full system pressure to the rear brakes in the event of a front brake system malfunction. Also, full front pressure is retained if the rear system malfunctions". This is a good design however you are still going to get more brake pedal stroke or run out of it with your pedal on the floor if one of the circuits fails, as Coop has mentioned above with his drawing.

If you're set on going with discs, I would do this from the start and would I would keep the current rear drums you and your wife will be pleased with the brakes. Key to all of this is stay as close to the application MC and WC sizes possible.

Glenn

Re: What Master Cylinder
 

Whatever brake setup you go with, make sure that the push rod gap to MC bore has a 1/16" to 1/8" gap. Also adjust your brake shoes such that they have a slight drag. Both of these adjustments will ensure that you don't have a lot of lost action in pressurizing your brake system and will give you full pedal stroke.


Be vigilant in checking for leaks and overly hot drums. You may have to tweak the brake shoes a bit until everything is bedded in well.


Glenn

Re: What Master Cylinder
 

Coop, yes in the end it is because I want to. I have plenty of rubber on the ground, I'm using '35 wires with the widest possible tires on them. Here is situation... I had planned on doing the brakes next winter but the existing mechanical brakes became extremely unsafe so I had to do something now. I simply don't have the cash for my ideal set up but I was able to buy the '40 style set up quite reasonably from a club member. I know of a man to is working on 4 wheel disc brakes that has a working prototype and is working on getting the rotors manufactured (Covid has set him back 2 years). When he has a system available I am going to go with that As far as I know the primary thing that makes it impossible to do the disc brake job is the 5 1/2" bolt pattern (I'm talking about the rear). I have worked out how I can get a 7" booster in the space. I am thankful that this conversation has gone in the direction it has I have learned a lot of great stuff and I wouldn't change it if I could. But... nobody caught what my real purpose of starting this thread was that I was asking for advice about what master cylinder to use in order to use a remote reservoir. I guess I did not frame my question well. I have since figured out how to avoid that so it no longer matters. I posted my question here on the V8 section because when I ask a "cuz I want to I get bombarded by "experts" telling me why "if it was good enough for the last 90 years it's the only way to do it". That's my story.

Re: What Master Cylinder
 

Hey '28 ....I caught the "REMOTE Fill" bit right off the bat. One of my pet peeves is folks jumping into a discussion that either just want to run their mouths because they can't find anyone to talk with, or those who clearly don't have a clue and want to offer advice and wisdom straight out of their collective posteriors. Hence, I generally try to refrain from commenting on that which I have no worthwhile answer for.

"Cuz I like your attitude".....I hope you'll feel welcome to visit this "V8 section" a little more frequently. You got a name, or does "Hey You" work well enough?

Coop

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Re: What Master Cylinder
 

Hello Coop, my name is Don Thanks for all your great comments/answers. I'm in western Washington a bit north of Seattle. Gary pops up on here from time to time and he lives on Whidbey island about 20 miles from me. I'll probably meet him some day. I'm going to stick with the banger on this one but if I ever get a chance to build another car I would probably go with a Model A again but I would seriously consider putting a Flathead V8 in it, that to me would be a perfect hot rod. Alas, finances and garage space make it unlikely that I will be able to do another.

Re: What Master Cylinder
 

When it's all said and done I will probably not need a remote reservoir but if I do I have a friend who has added them to a regular MC with very good results.

Re: What Master Cylinder
 

Over on the HAMB there is a guy selling "A Corvair disc brake set up off of a 34 Ford. For the money he's asking $200 it could be a good deal for me. I'm concerned about what would be required to install it on a Model A. He is including the spindles which I think will go on a Model A axle, yes, no, maybe? He also mentions S10 but I'm not sure what is Corvair and what is S10. I would need to use an adapter from 5 x 4.75 to 5 x 5.5 to use my '35 wires and a support ring as well. Good deal? Bad deal? Buy it? Run away? It is the dang 5x5.5 lug pattern is what makes this project difficult. There are plenty of pieces available that use the smaller patterns. It probably would not be possible to drill the 4.75 rotors to change it to 5.5? Thanks again. Don

Re: What Master Cylinder
 

Yo, Don - Coopman here...remember me? You seem like a nice guy that's seriously trying to put together a nice & simple, yet fun and reliable car that'll provide miles of smiles for you and Momma, and with a reasonable, yet prudent outlay of cash. So, for what it's worth, and keeping in mind "WHAT THE HECK DOES THIS Coop GUY KNOW", I'm gonna suggest that you run away from that Corvair and S-10 disc brake and spindle junk like a mad man.

I know what the 16" '35 wire wheels are. I like 'em....A LOT! Love them on a Model 'A'. But NOT knowing much (if anything) about the possible combinations that you might end-up with trying to make that stuff work on your I-beam, and I'm assuming a Model 'A' banjo-type rear end (?), one of the worst possibilities that you can end-up with is those wire wheels sticking-out way too far in relation to the fenders. You start running wheel adapters, plus the fact that many disc brake rotors tend to mount wheels farther outboard than brake drums would, is a possible situation that may come back to haunt you big-time. You mentioned that the Chevy spindles may be adaptable to the Ford I-beam. That in itself does not guarantee that the CAMBER angles will be anywhere near correct, as that angle is generally set in stone with each individual spindle design. Steering arm and tie rod arms also come into serious question whether or not their positions would be conducive for use with your steering box. If, for some self-satisfying reason you are determined to put discs on all four corners, we can likely figure a couple of MORE-REASONABLE ways to accomplish that end than by wasting $200 big ones on those old Ralph Nader parts. For what it may be worth, I would be willing to HELP you figure-out a plausible path toward your goal. I'm just throwing my .04 cents worth 'cuz you asked. I KNOW that there are better ways to do this than trying to adapt that Chevy stuff.

Are we actually talking about a '28 ROADSTER PICK-UP, or some other type of Model 'A'? What type of rear end? Stock A-bone steering? Stock, mechanical brakes currently?

Coop

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Re: What Master Cylinder
 

Coopman Excellent, I'm just about ready to add fluid to my system. I'll let you know how it works.
Gramps

Re: What Master Cylinder
 

Mr. Coopman, I hank you for your kind offer. I'm off to work now but will get back to you later this evening. I will take your advice and steer clear of the Corvair stuff but I should mention that the set up had come off a '34 and was including the spindles which I was thinking (probably in error) that they would be a fairly straight forward swap. Thanks again.

Re: What Master Cylinder
 

Hey Don....I believe the first thing I would have to ask would be: "WHY are you removing these great parts from your '34 Ford?"

I'll keep this short, but below is a Corvair spindle which mounts between upper & lower A-arms, via ball joints.

https://www.bing.com/th?id=OIP.ctvF9...5&pid=3.1&rm=2


Below the Corvair spindle is an old Ford spindle....NOTE kingpin angle which coincides with angle of kingpin boss on I-beam, resulting in proper CAMBER (spindle is pictured upside-down).

https://www.bing.com/th?id=OIP.dOzL9...5&pid=3.1&rm=2


NOTE the angle of the KINGPIN BOSS in a Ford I-beam, corresponding with Ford SPINDLE's Kingpin angle.


https://th.bing.com/th/id/OIP.Gms8iR...r=1.25&pid=1.7

Seen in this last photo is a complete Corvair Independent Front Suspension as the unit unbolts from the Corvair in one piece. Back in the '70s there were a bunch of clowns bolting these entire units under the front of Model 'A' thru '48 Fords. They make the car look atrocious. I wonder if that's what your H.A.M.B. guy had done?


https://i.ytimg.com/vi/MUOS_Z36o8I/hqdefault.jpg

Re: What Master Cylinder
 

Is there such a thing as a disc brake set-up that works with '35 wires.

Re: What Master Cylinder
 

Posies offers a front disc brake kit that uses V8 spindles ($350) and 5x5 1/2" rotors etc ($690) Probably still requires the support plate for the wires ($25 each). All in all not a horrible price I don't think (still an awful lot of cash though). If you had some spindles already it gets a lot better. Where the problem really lies is with the rear, as to my knowledge there is nobody offering the rotors for the rear with the 5x5 1/2" pattern so adapters would be required. And also I thought I should try and clarify about the Corvair set up (I thought somebody might cruise over to the HAMB and check out the ad and determine exactly what is involved) the seller says that it came off a 34 Ford stock front axle including '34 spindles, NOT Corvair spindles. It looks like a pretty good deal for $200 (keep in mind I just said Posies want $350 for spindles). The problem I see is that lug pattern adapters would be required which in my case would set the tires out enough for tire/fender clearance issues. I also know from experience that the adapters can increase the occurance and severity of "Death Wobble" already a problem on a Model A. (the guy is selling because he apparently makes $ building nothing but '34 Ford Hot Rods with drop axles) Anyway, for the reasons given, I'll pass on the Corvair stuff.

Re: What Master Cylinder
 

Also, Coopman, yes, it's an RPU ('28). I believe that I now have the master cylinder situation solidified and plan to use the Cardone.