Brake Conversion? Or not.

T

Tveditr

Member
My 18 Year old son owns 1930 Ford Model A . He has done a lot of work on this car and enjoys it. The one thing he isn’t happy with is the original friction brakes. He is considering upgrading to hydraulic brakes. I would like some thoughts about this conversion and hear if there are any recommended kits to accomplish this
 
Some like 'Yin', and some like 'Yang'.

It depends on what he's done to the car. Original? Restored? Rod?

My experience has been that original and restored cars with hydraulic brake conversions re-sell for less money. Customs and rods with hydraulic brakes re-sell for more money.

Your results may vary.
 
My vote is don't do it. Mechanical brakes PROPERLY RESTORED will stop the car just as quick as hydraulic. The skinny tires are the limiting factor. Hydraulics won't help that.
 
If the stock brakes are in top condition they will stop the wheels from turning. This is what the hydraulic brakes do. Soooo what's the point. Model A tires have a small footprint which is more of an issue when compared to modern tires.
 
I can skid all 4 tires on my '31 Town Sedan on dry pavement with the mechanical brakes. And this is with the larger V-8 wheels/tires on the car (more rubber on the road). There is nothing wrong with mechanical brakes when they are right.

The biggest problem with mechanical brakes is worn parts that the restorer is too cheap or too lazy to replace. When everything is right, like original, and adjusted properly, the mechanical brakes are really good. And all the parts you need are available.

One thing that Model A brakes need is occasional manual adjusting, to account for brake lining wear. It's a bit more often when the brake linings are new, until they wear in. Hydraulic brakes still have to do this, too.

I believe your son will have a greater sense of pride and accomplishment if he restores the brakes as they were originally. It is a different type of system, so it will require him to learn some new skills; nothing wrong with that. The pride of having restored it back to original will mean a whole lot later.

My opinion. YMMV.

:cool:
 
wmws said:
My vote is don't do it. Mechanical brakes PROPERLY RESTORED will stop the car just as quick as hydraulic. The skinny tires are the limiting factor. Hydraulics won't help that.
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Ditto on that. Problem with hydraulics is that everyone uses the 1940ish hydraulic brake backing plates, drums, shoes, and "conversion kit." Which if you started with the rightly proportioned brake cylinders and other parts, would work fine.

Problem is the 1940 plus Ford cars were half again as heavy as the Model A, had the advantage of wider tires, and different (more even) car weight proportioning between front and back. The majority of braking on any car occurs on the FRONT because of the moving inertia of the car, the location of the car center of gravity above the road, and from this a natural tendency for the tire front loading to be greater than the rear.

The problem with the 1940s era backing plates (other than physical differences causing one to "slot" bolt holes, put holes in it to clear the spring perches, and use space rings AND go to the larger diameter drums) is that this "proportion" is all wrong.

Not that it can't be corrected. Brake design is an entire science of its own. And experts have always had "aftermarket kits" for putting hydraulic brakes to non-hydraulic vehicles (Ruckstell started with the Model T IIRC) and more recently disk/caliper combinations which can be VERY finely matched to the car. Some of these latter adaptations can be hidden within the existing brake drums and can be visually unobtrusive. A factor I might favor - unless the objective is to be seen as "different," which motivates some.

But for all this engineering you pay a pretty penny - and if you're going to keep the existing 19 or 21 inch wheels, there is hardly a point to paying all that extra for it. Hydraulics will NOT improve your braking power, and might even hinder it. The rubber to the road is the brake limitation. With hydraulic brakes you may not be able to correct in adjustment - at least not without contacting the manufacturer. And assuming they "engineered in" an adjustment.

For my opinion, the best bang for the buck you can do to improve braking is to get away from the pressed steel drums and put on cast iron drums. Pressed steel not a great idea when Henry adopted them. I suspect they were more a cost saving expediency in mass production. Plus the drivers of the day were used to the Model T of which the Model A even with pressed steel drums was head and shoulders above in stopping ability.

Even Ford late in production went to cast iron drums, and a similar cast iron ring with a pressed steel center for the later Ford hydraulic brakes.

The original 1928 mechanical brake design was actually quite superior in that it gave a "self-adjusting" modus. The split brake actuating shaft corrected any developed bias in the brakes left to right evening pad pressure left to right. The later non-split brake actuating shaft was a step backwards, but not a fatal one, and pad pressure can be evened out.

And brake "floaters" tend to improve and even out the pad pressure within the wheels themselves. It is a function that is already "built in" to the Ford design, but the floaters achieve the same equalization with less tendency of hang-up.

Going on...

Fords own instruction for adjustment of mechanical braking is counter to what most might advocate today, and certainly different from modern cars. Ford in his instruction "biased" the brakes to the rear to cause the rear wheels to grab first in the rationale that "this will keep the car from swinging around and doing a 180 in the stop." Ford apparently never came to the thought that once a tire skids - it's useless as a brake. Rather, the best braking occurs just at the margin before the rubber leaves the road, i.e. incipient skid.

Today ALL manufacturers bias the brakes so that the front tends to grab first - drivers today are used to it and the term now used in auto education to describe the natural reaction in panic stopping of "steering the skid." Rear bias will not allow this with a tendency for the car under the action of steering the skid to swing around and do EXACTLY do what Ford was trying to avoid by rear bias. IMHO rear bias CAUSES accidents and deprives drivers of a useful tool for accident avoidance.

A forward brake bias takes advantage of inertia and the additional rubber pressure on the road for a quicker stop. And with it a panic stop can be "steered" successfully and keeping the wheels in line.

Getting to this point with mechanical brakes CAN be a challenge - but the adjustment is intuitive - you do what seems to make the brakes work BETTER.

There are instructions online about using "measured sticks" and gauging action of the brakes against the sticks. These work, but give you basically a "starting point" for finer tuning of brake capability.

I myself use a road with a fine layer of sand or gravel. This I find gives the best proportion front to back, and you can tell by the skid marks which wheels are grabbing first, and how evenly left to right.

Dad used to do the same thing in a driveway covered in pea-stone back in the 1930s.

Anyway, a lot here all at once. And no doubt will be a "seed for discussion."

Joe K
 
wmws said:
My vote is don't do it. Mechanical brakes PROPERLY RESTORED will stop the car just as quick as hydraulic. The skinny tires are the limiting factor. Hydraulics won't help that.
Click to expand...

I totally agree! But if he has his mind made up this forum isn’t going to change it!
 
I used to have a 39, and a 46, was working on the brakes too often, a little leak and the shoes were contaminated causing pull, and total brake failures, got tired of it, now have the A(no brake problems in 50 years of owning), and a 36 because they have mechanical brakes, when I first got the 39 I did side by side comparison, the A stopped in less distance from 50, and was still stopping after the 5th stop when the 39 brakes faded out----
 
wmws said:
My vote is don't do it. Mechanical brakes PROPERLY RESTORED will stop the car just as quick as hydraulic. The skinny tires are the limiting factor. Hydraulics won't help that.
Click to expand...

I also agree!!!

I highly recomend using the original woven linings. The replacement molded linings are way too hard and have less coefficient of friction and you have to push a lot harder to get the same stopping force. The woven linings are softer with as higher coefficient of friction and will stop a lot better with less pedal effort.

Also, as previously stated, everything must be properly restored with the shoes arced to the drums and centered on the backing plates and the brakes adjusted correctly.

I think it is a lot less work to correctly restore the mechanical brakes than convert to hydraulics and the end result will be better.

My experience and my opinion,

Chris W.
 
When I was 18 I was throwing good money away at totally unnecessary car stuff. Quite the learning experience. Switching to hydraulic brakes on a stock Model A is a waste of time and money. Learn how to adjust them and you are good to go.
 
Tell your son that every ten years or more he will be replacing rusted brake lines, fixing leaking wheel cylinders, and master cylinders on a more regular basis. The Model A brakes from the factory will still work the same today as when the car was parked 60 + years ago.
 
This really falls in the same category as turn signals, 12 olt conversion, seat belts, V-8 clutches, electronic ignition, etc. Just a matter of how far from original you are willing to go. Ultimately up to each owner to mod as they choose. If going the hydraulic brake route, recommend pugtting all the original parts in a box in the eent the next owner wants to demod to original brakes. I am pretty happy with the mechanical brakes on my 31 - but do have the mods mentioned above mostly for safety and reliability.
 
You will spend more time and money screwing around with hydraulic brakes than you will if you properly refresh and adjust the mechanical brakes as they are designed. After all, if you can skid with mechanical brakes, you can't skid any more with any other kind of brakes. By the way, I think rather than friction brakes, you might have meant mechanical. All brakes operate on the basis of friction.
 
if your gonna do it, check the swap meet here today. Battery box for master cylinder set up. I used this and many others have.
 
This has been covered at great length.
In my limited experience with two A's
Mechanical breaks work great but most cars not done completely to achieve good results.
Plan on spending $2,000 +
Rebuild all internals, tracks rollers springs etc.
Cast Iron drums
Shoes
Brake rods/ends pins etc.
Proper adjustments

By the time you do all the stuff for HD brakes might cost more.
 
One of the problems that most have with mechanical brakes is slack left in the brake rod connections . I first adjust the back wheel brakes with the tires on the ground or shop floor . I can feel the drag best by pushing with the weight on the rear wheels . The way that the shoes were set up on the rear will cause drag on the top brake shoe if the brakes are adjusted the least bit too tight and the drag on the rear can be best felt with the weight on the tires . The reason is there is one shoe on top and another on the bottom and the weight of the car will take up slack and cause the weight to be on the top shoe if the adjustment is too tight . The front brakes have one shoe in the front and the other at the rear and weight doesn't effect brake adjustment as much . I adjust the front brakes with the car on stands. I then adjust so that the front brake levers lean forward about 15 degrees . I adjust the brake rod clevises so that the brake pins will just enter through the clevises and levers . This removes the slack so that the brakes are right ready to activate when the brake pedal is pushed . No matter how many parts were replaced or how much money was spent , If slack remains in the brake rod setup , the brakes will be poor .
 
If all you want to accomplish is a good braking system and leaving the A in "stock" form.......

From my experience:
Hydraulic or mechanical done right are both good.

As mentioned mechanical brakes for the Model A setup correctly with the proper parts IMHO are as good as hydraulic. I know cause I have done both.
My coupe with mechanical brakes stops as well as any hydraulic brake conversion I have done.

Downside to the hydraulic conversion is the cost and finding really good parts especially
the wheel cylinders. The new ones made today are not up to snuff so, if going this route find the very best originals you can and rebuild them properly.

Henry didn't make a bad braking system on the A. On the contrary, they did a very good job and the setup works very well.

Maybe take the time to look into what is needed with the current setup, sit down and weigh the cost to fix or convert.

On the other hand, if you are headed to a "Hot Rod" with much more horse power........hydraulics it is!
 
The issue with most brake jobs is a failure to have drums and shoes matching in diameter and centered (for the mechanical brakes).

You need this for either system and it is just not done. What is worse is I did a 65 Mustang with made in china parts and the shoes and drums were just not even close, but that is another story.

If you do not have 100% contact you do not have 100% brakes. It is just that simple.

Steel drums are just not going to work well. Most steel drums are too worn to be used. Cast iron are just so much better.

The best thing you can do is pay for one of the online shops to make a set of drums matched to backing plates with all new parts. You bolt the new brakes on your axles and are likely to not have to worry for the next 40 years.

Juice brakes just suck. The wheel cylinders in the rear get mucked up more often then you would like. What is scary is to talk to guys at the car shows. You might be surprised to find a significant number cars with juice brake that have one or more wheel likely not working. Keep in mind this is for all years of cars!!!!

Spend the money to properly rebuild the A brakes to mechanical and never worry about them again.
 
Well ... seems as I am in the minority here. All the above responses include "if everything is in good shape and adjusted properly" important conditions. I disagree with the idea that you will be plagued with rusty lines and cylinders. It is true that DOT 3 or 4 will attract moisture, DOT 5 (silicone) rejects moisture, so will eliminate any of those supposed problems. '39-'48 Ford brakes were designed for heavier cars, so do even better on cars the weight of our A's. They will not apply the front brakes before the rears, neither applies first, by the nature of hydraulics. Hydraulics do apply more breaking power to the front, where it is needed. I have 3 Model A's, all with hydraulics, I prefer the '39-'41 style, but that's just me. I ran my speedster for a couple of years with stock 'A' brakes, then went to 35's on the rear. That helped but but were still not what I liked. I am now somewhat handicapped, and don't think I have the leg strength needed for mechanicals. How often have you, or anyone in your family, ever had a problem with brakes on a modern car? Most can answer "never" to that question.

Bottom line, IMO, is if your son is not happy with the mechanicals, he'd be smart to go to hydraulics. Say what you want, but under hard usage, hydraulics are safer. Being 18, he might be prone to faster driving, and could even suffer from distractions at some time. I wish him happy motoring!
 
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