disc brake conversion

[1917modelt]

can i install disc brakes on my 1928 model A and still use the stock
wire wheels.
and if i can, who sells such a kit, for all 4 wheels

thanks

[BILL WILLIAMSON]

Ron Kelleys' Sister once listed her Model A for sale, with 21's & DISC BRAKES. I Imagine Ron built it, but I don't know what components he used???
Bill W.

[Wareagle]

Check with speedway. They sell all kinds of brake conversions for the hot rod gang.

[2manycars]

Post the question on the HAMB and you will probably get better results, as the hot rodders may have already done this.

[modelAtony]

Originally Posted by BILL WILLIAMSON

Ron Kelleys' Sister once listed her Model A for sale, with 21's & DISC BRAKES. I Imagine Ron built it, but I don't know what components he used???
Bill W.

Bill, this was Ron Kelley's DAUGHTER . Her 28 Tudor, had it thru high school and later . Met him at the 2008 world meet in Dallas, TX and she had it for sale later. Not sure where it is now. It had 4 wheel disc and you didn't really notice because of the 21" wheels. Have fun modelAtony tony white Lafayette, LA

[160B]

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Here are some photos and notes of the major components used to install hydraulic disc brakes on a Model A Ford that I saw in Tasmania in 2010.

[Rowdy]

Speedway now sells the disk brake kits for the 37-41 spindles with the 5 on 5 1/2" bolt pattern. Not much trouble to put 37-41 spindles on an A axle. Steering arms are the biggest challenge. Rod

[Rowdy]

Another challenge will be the support of the hub flange of the original wheels. Rod

[Charlie Stephens]

Wish I could be more helpful but disc brakes are a dark place where I don’t want (or need) to go.

Disc brakes are great. Disc brakes are “probably the greatest thing since sliced bread”.

With disc brakes you can stop several times in rapid succession from 100+ MPH (are you going to be doing this, otherwise drum brakes will work just fine?).

With disc brakes you can stop safely while towing a heavy trailer (are you going to be doing this, otherwise drum brakes will work just fine?).

With disc brakes you don’t have to worry about brake fade when going down steep mountain roads (any plans to go down the Beartooth Highway in Montana, it's beautiful?).

With disc brakes you don’t have to worry about brake fade when fording streams or flooded streets (does it rain a lot where you live?).

With disc brakes you don’t need to find someone to turn your drums and arc your shoes every 20 years when you do a brake job (at the rate I drive).

With disc brakes you can enjoy explaining at a car show what all that “funny” stuff is attached to your axle.

With disc brakes you can enjoy cleaning the brake dust off of the wire wheels. Something people with drum brakes can’t experience.

With disc brakes you can take pride in having something unique. You can mix and match parts from several makes and years until they all work together. Why just use ’40-’48 Ford brakes (or Lincoln brakes) like everyone else when you can experiment with disc brakes. A brake system is a great place to experiment (hope it comes out well, let me know when/where you will be doing your test drives).

By all means install disc brakes, but I will stick with drum brakes.

Charlie Stephens

[1930artdeco]

One guy in my club had them on his T.

Mike

[Mike V. Florida]

Originally Posted by 1930artdeco

One guy in my club had them on his T.

Mike

Actually not so rare to see disc on T's.

[fiftyv8]

Disc brakes mostly need boosting so consider that also.
You will need a vacuum supply.
I know some vehicles had disc brakes in the past that did not boost them, I owned one such vehicle but I also could not recommend that set up.

I know I spoke with a guy from Melbourne Australia several years ago and he was fitting drum brakes from an early model Holden and down sized Chevy looking vehicle from the 1960's to his model T and he seemed to think that was the way to go.

Ford juice brakes go well on model A's and pretty much have been tried and tested.
Disc brakes topic at times is not one you expect much sympathy on the HAMB as they are a more traditional bunch...

[Pete]

"Disc brakes mostly need boosting so consider that also."

Absolutely WRONG.

[jaguar6165]

I would love a set up like disc brakes on mine. I know its over kill and can be argued forever, but driving it on a daily basis in Central Fl traffic is a bit of a thrill and not always the good kind. People cant drive around here and have no problem cutting off a car that doesn't stop as quickly as theirs. I would love hydraulic drums too, just time and money I guess..

[jw hash]

here is one I that I put together a while back. and use 16" wires. and there is a big problem with this set up using Model A wheels. on Model A wheels the brake Drum is part of the structure of the wheel, without the drum the full side load is put on the lug nut area and they will not take it for long, even the 16" wires are designed to be against the drum, but they can take more of a side load. also you have to space the wheels out from the hub over 1"

just my two cents

[updraught]

Ebay has an original Model A disc brake vacuum hole

http://www.ebay.com/itm/model-a-ford...3D281900162968

[fiftyv8]

Originally Posted by Pete

"Disc brakes mostly need boosting so consider that also."

Absolutely WRONG.

Please explain wise one???

[Bruce of MN]

Originally Posted by fiftyv8

Please explain wise one???

"Mostly" is applicable. My '66 Triunph TR-4A has discs on the front and no booster, but it was an option. Ditto for my departed '77 Chevette.

[gweilbaker]

My 1972 Ford F-100 Ranger with front disks was manual.

[Rex_A_Lott]

Originally Posted by fiftyv8

Please explain wise one???

You wont live long enough to count all the race cars of various types running around with disc brakes, and none of them are powered....I believe that is what Pete is referring to with his statement, and I agree with him, for once.

[BRENT in 10-uh-C]

Originally Posted by jaguar6165

I would love a set up like disc brakes on mine. I know its over kill and can be argued forever, but driving it on a daily basis in Central Fl traffic is a bit of a thrill and not always the good kind. People cant drive around here and have no problem cutting off a car that doesn't stop as quickly as theirs. I would love hydraulic drums too, just time and money I guess..

I honestly believe your mindset is the same as many others. There is a (false) sense of security that comes with disc brakes however the issue is not stopping the wheel from turning, -but more about stopping the tire from sliding. On a rebuilt to factory specs stock braking system, I can make 9 quick 40-0 mph stops and on the 10th time, I can slide all four tires. A set of disc brakes cannot do any better.

[George Miller]

My 66 Corvette has disk brakes, on all 4 wheels. non power. You wont find a car with better brakes.

[George Miller]

Originally Posted by BRENT in 10-uh-C

I honestly believe your mindset is the same as many others. There is a (false) sense of security that comes with disc brakes however the issue is not stopping the wheel from turning, -but more about stopping the tire from sliding. On a rebuilt to factory specs stock braking system, I can make 9 quick 40-0 mph stops and on the 10th time, I can slide all four tires. A set of disc brakes cannot do any better.

I could not agree more. A lot of the model A,s that I have seen, the brake parts are all wore out. They have good brakes when they are fixed right.
I worked on one guys car that had 40 Ford hyd brakes on it, what a mess. You could put both feet on the pedal and it would not stop. Cylinder was hung from the battery box. Had the wrong leverage, some copper lines not supported. It was just a mess. He use to go on tour with us, not fit to be on the road. After that I won,t work on cars with rigged up brakes. Don't need a law suite.

[Pete / MA]

Don't forget that "tire footprint" is also a consideration when comparing brakeing or "stopping" ability.

[fiftyv8]

So you guys are telling me that disc brake mostly don't need vacuum.
I know they didn't always in the distant past come with boosting, as I stated I owned a car without boosting and was glad to enjoy the luxury of a boosted system.
For every race car you say I need to count there would be ten fold more production cars that have boosted systems.
So I am just wondering why my statement deserved to be WRONG...
I hardly see the relationship between that of driving a restored Model A Ford to that of a race car.
I would think better brakes would be considered to preserve a nice old car having to run amongst modern day traffic.

I like juice brakes as they seem to be the best middle of the road way to go with better braking and compatibility with wheels...

[mhsprecher]

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My town sedan has great brakes. Cast iron drums, all done before I bought the car. I do adjust the brakes myself and get excellent results.

I want to do some tests to measure stopping distances to get some real data and compare that with my daily driver 2013 Focus - just so I know. What we think is happening and what is actually happening can be very different. It might be a fun club activity to do some tests.

What worries me most about my car is the tires. There is only so much friction area where the tire meets the road.

[mike657894]

sooooo on the boost debate. discs brake calipers dont need a booster, the master cylinder you may use may need a booster. the booster is to make the brake all nice and super easy to use. get in a large boosted old caddy and see why everyones grandma loves it. it needs next to no pressure from the foot. so hydro pressure is a combition of the force on your piston/ the size of the the master cyl in relation to the size of slave cyl/ the pivot point vs levrage against the point applied to the piston. get a master cyl designed for manual and it should be fine. or a formally boosted cyl and increase leverage by moving the pivot point. but if your brakes scare you in traffic they need to be adjusted. i hit the brakes on a snowy gravel road at about 30 and had to quickly remeber all the things you need to know about bringing a car out of a 4 wheel slide and keeping it out of the trees.

[Pete]

A typical thread on any common car subject will have 99% of the answers relate to personal experience or repeating an experience of a friend, NOT, engineering data derived from testing.
A properly designed disc brake system on a passenger car does not require power assist. It won't stop the car any quicker. Originally it was a sales gimmick and people liked it because they perceived that the car stopped quicker.

[Rex_A_Lott]

Originally Posted by fiftyv8

So you guys are telling me that disc brake mostly don't need vacuum.
I know they didn't always in the distant past come with boosting, as I stated I owned a car without boosting and was glad to enjoy the luxury of a boosted system.
For every race car you say I need to count there would be ten fold more production cars that have boosted systems.
So I am just wondering why my statement deserved to be WRONG...
I hardly see the relationship between that of driving a restored Model A Ford to that of a race car.
I would think better brakes would be considered to preserve a nice old car having to run amongst modern day traffic.

I like juice brakes as they seem to be the best middle of the road way to go with better braking and compatibility with wheels...

Maybe its just a little confusion between WANTS and NEEDS. A lot of people will WANT the boosted system, so, as someone pointed out, anybody's Grandma can step on the pedal and have plenty of force make it to the caliper. But it doesnt NEED boost to be an effective system. Maybe WRONG was too harsh of a word for you. We just have a different opinion of our NEEDS. But you are correct, many more people want them and think they need them , boosted.
Just like no one NEEDS disc Brakes, but they may think they do, and maybe if they WANT them bad enough they will put them on. If it means they feel better about the old car and take it out on the road and enjoy it, then more power to them....but its no longer a RESTORED Model A now is it?
Let's not get all hung up in the wording, somebody may get some good info out of this thread yet.

[pgerhardt]

Originally Posted by BRENT in 10-uh-C

I honestly believe your mindset is the same as many others. There is a (false) sense of security that comes with disc brakes however the issue is not stopping the wheel from turning, -but more about stopping the tire from sliding. On a rebuilt to factory specs stock braking system, I can make 9 quick 40-0 mph stops and on the 10th time, I can slide all four tires. A set of disc brakes cannot do any better.

Oh now you have done it! How long will it be before we get a post asking how to install an anti-lock brake system on their model A?

[updraught]

How do you install ABS?

[bikejunk]

Originally Posted by fiftyv8

So you guys are telling me that disc brake mostly don't need vacuum.
I know they didn't always in the distant past come with boosting, as I stated I owned a car without boosting and was glad to enjoy the luxury of a boosted system.
For every race car you say I need to count there would be ten fold more production cars that have boosted systems.
So I am just wondering why my statement deserved to be WRONG...
I hardly see the relationship between that of driving a restored Model A Ford to that of a race car.
I would think better brakes would be considered to preserve a nice old car having to run amongst modern day traffic.

I like juice brakes as they seem to be the best middle of the road way to go with better braking and compatibility with wheels...

I live in northern New Jersey it dont get no tougher than that when it comes to traffic I use properly adjusted stock brakes - you use what makes you happy -

[fiftyv8]

One brake idea that did catch my attention some years back out of CA I think, was a vacuum actuator device that was attached to main central brake lever bar under the central cross member that looked like it boosted stock mechanical brakes.

I would liken it in appearance at least but smaller in size to the actuators (hoping the term is right) that can be seen on the axle of a semi trailer at each wheel.

I am guessing it was not popular or had some issues as I have not seen it promoted anywhere for a long time now.

The idea seemed sound but who knows...

Has anybody out there seen or used this device and may have some feedback about its performance.

[Model A Man]

I always wonder if mechanical disc brakes would be possible!

[fiftyv8]

Could it be that the mechanical park brake part of some disc brake calipers would be good enough to stop a model A better than the original brakes?
That is just a question not a statement...

[dumb person]

Originally Posted by fiftyv8

Could it be that the mechanical park brake part of some disc brake calipers would be good enough to stop a model A better than the original brakes?
That is just a question not a statement...

Few cars now days have disk parking brake. While it is fun to entertain the idea i have noticed that the few cars i worked on with disk parking brakes had a threaded shaft type thing that that pulled or pushed the pads together. The 'nut' on the thread ratcheted. In order to replace the pads they had to be wound out again. Self adjusting but.... i forgot where i was going with this, i think it was something to do with losing mechanical leverage unless you made many trick parts for such a conversion.

[Dodge]

Don't laugh we are fabricating an ABS system right now on a 1948 for station wagon. We did one on this customers 1964 Fairlane and he liked it so much we are doing the wagon now.

[fiftyv8]

There was a late model Ford sedan (mid 1990's) that I saw which had from memory, rods that pulled on the caliper into the center of the diff for parking brake and then a cable that went forward to the hand brake lever.
That was the kind of thing I was thinking off.
Still does not give you disc brakes up front, I guess and not everybody likes cables...

[Charlville]

My 1966 Triumph Herald has discs with no servo

[Bruce of MN]

Originally Posted by Model A Man

I always wonder if mechanical disc brakes would be possible!

There are a few used on motorcycles, '60's MV 600 for one (but they weren't supposed to be very good):

[jrapose]

I have had disk brakes on my roadster for years....with no vacuum assist..and I would not want one...it stops easy and quickly...works fine...there are some tricks though...

The kits most places sell will not work using wire wheels...there is too much setback on our rims to allow for the caliper clearance.... it won't work using our wheels...

The rotor hats I used were Suzuki Samari ....they are 5 on 5 1/2 pattern and have a large setback... the calipers I used were Willwood brand but Volkswagen would also work...

You will want to use a AMC master cylinder as the outlets are on the oposiite side than a Chevrolet dual master....you will be mounting the master cylinder backwards so you want the outlets pointing toward the frame... you will pull the tube seat out of the front part of the master cylinder as you don't want residual pressure in that front line...or you will drag your disks..

By using deep rotor hats you will position the rotor surface in line with your kingpins so it will not cause any kind of pull in a panic stop...plus you will not need to space your wheels out...I think that kinda look mickey mouse when I see a car where they have done that...

I use 40 Ford rear drums so I use a late model Ford proportioning valve that I make adjustable...(easy to do).. but you can buy adjustable valves if you want.
The only thing I would like to do now it to change the backing plates on my drums to make them servo brakes ....as they are now they have 2 anchor positions ....and do not self energize.

Joel
Retired College Shop Teacher

[Marvin/TN]

Check with ECI (Engineered Brake Components) 860-872-7046. I bought a kit from them to to put Disc Brakes on my 46 Coupe but kept the drum brakes on the rear.

[Brendan]

Originally Posted by 2manycars

Post the question on the HAMB and you will probably get better results, as the hot rodders may have already done this.

not there eather

[jrapose]

Sure it will work on your 46 coupe...but that does not have Model A wires...and the rim on your 46 is almost flat...the A has a huge setback in the rim...

Joel

[fiftyv8]

Is there anybody here who has 4 wheel disc brake set up without boost???
What set up did you use and what feedback can you offer???

[Pete]

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Originally Posted by fiftyv8

Is there anybody here who has 4 wheel disc brake set up without boost???
What set up did you use and what feedback can you offer???

Yes. I have a complete Wilwood kit on my 30 2door. No power.
Swing pedals, dual cylinders with adjustable bias bar, mechanical parking calipers, carbon fiber pads, et al.
I used the Wilwood aluminum hubs so I could run aluminum wheels. This essentially the same setup I have on my race car.
When I first did the conversion I made up a set of model A wheels to fit but later decided I wanted more rubber on the ground. I don't do parades or shows any more so I don't need the original look.

[jrapose]

Anyone have an idea where I can locate some rear servo style backing plates ? or better yet, an idea of what servo brakes would work in the rear with a parking brake??


Joel

[V8COOPMAN]

Originally Posted by Pete

Yes. I have a complete Wilwood kit on my 30 2door. No power.
Swing pedals, dual cylinders with adjustable bias bar, mechanical parking .

Heck, using two M/Cs with the appropriately-sized bores and a bias bar makes it a piece o' cake, 'cuz the required fluid volume (using two M/Cs) isn't compromised by running out of available pedal stroke first, as is usually the case with a single (appropriately-sized bore) M/C in an UN-boosted system.

If a M/C's diameter is small enough, and the available stroke of the piston is long enough to supply the volume of fluid required at the four wheels, AND if the pedal travel is available to facilitate that piston stroke (at an appropriate and comfortable pedal ratio), then NO.....you wouldn't need a booster. Trouble is, in the real world, M/Cs don't have a long-enough stroke (at the proper diameter), and the pedal doesn't have enough available stroke. In most cases, the best COMPROMISE is a booster, with the pedal ratio optimized, and with the M/C diameter sized just a tad too big. DD

[Pete]

Originally Posted by V8COOPMAN

Heck, using two M/Cs with the appropriately-sized bores and a bias bar makes it a piece o' cake, 'cuz the required fluid volume (using two M/Cs) isn't compromised by running out of available pedal stroke first, as is usually the case with a single (appropriately-sized bore) M/C in an UN-boosted system.

If a M/C's diameter is small enough, and the available stroke of the piston is long enough to supply the volume of fluid required at the four wheels, AND if the pedal travel is available to facilitate that piston stroke (at an appropriate and comfortable pedal ratio), then NO.....you wouldn't need a booster. Trouble is, in the real world, M/Cs don't have a long-enough stroke (at the proper diameter), and the pedal doesn't have enough available stroke. In most cases, the best COMPROMISE is a booster, with the pedal ratio optimized, and with the M/C diameter sized just a tad too big. DD

Yup, all that is true, BUT, I have a single master cylinder
on my race car with the essentially the same kit and I can VERY EASILY lock up all 3 brakes at 110 mph at the end of the straight.
As I see it a power booster is added to compensate for poor engineering. A cheap way out.