Upgrade your 1928-1931 Ford Model A with a Model A Disc Brakes hydraulic brake conversion kit.

Hydraulic Disc Brake Kits for Front or Rear

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Upgrade your 1928-1931 Ford Model A with a Model A Disc Brakes hydraulic brake conversion kit.

Hydraulic Disc Brake Kits for Front or Rear

Shop Now

About Model A Disc Brakes

A serene landscape featuring a sunset over a calm lake surrounded by trees and mountains.

Why Model A Disc Brakes?

Model A Disc Brakes LLC provides high-quality hydraulic disc brake kits specifically designed for 1928 -31 Ford Model A cars.

Unlike other hydraulic brake kits, these kits allow you to:

Keep the stock wire wheels
Keep your original spindles
Keep your original hubs
Keep your original steering components

This reduces your investment and allow

Model A Disc Brakes LLC provides high-quality hydraulic disc brake kits specifically designed for 1928 -31 Ford Model A cars.

Unlike other hydraulic brake kits, these kits allow you to:

Keep the stock wire wheels
Keep your original spindles
Keep your original hubs
Keep your original steering components

This reduces your investment and allows your car to be returned to original if desired.

These Model A Disc Brake kits are for use with stock style wheels and tires (late 1928-1931 Model A, 1932-1935 Ford).
To complete the kit, (per axle) buy 2X 2004 Kia Sorento REAR rotors, 1X left and 1X right GM Metric front brake calipers and matching brake pads.
The builder must supply appropriate brake lines and master cylinder.

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A serene landscape featuring a sunset over a calm lake, surrounded by mountains and lush greenery.

Why believe Gene Garrett?

As a retired Professional Engineer, I have designed brakes for race cars and motorcycles, and components for satellites and the International Space Station.

I have fun with my Model A and want to see the average owner able to install hydraulic brakes in these fun cars.

If you want hydraulic disc brakes for your Model A, here is a reasonab

As a retired Professional Engineer, I have designed brakes for race cars and motorcycles, and components for satellites and the International Space Station.

I have fun with my Model A and want to see the average owner able to install hydraulic brakes in these fun cars.

If you want hydraulic disc brakes for your Model A, here is a reasonably priced solution; if you are building a hot rod, this is not your answer.

If you are building a hot rod with wide/offset tires, you want to talk to one of several suppliers like Speedway Motors, Pete & Jakes or Posie's.

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Front Disc Brake

Items purchased separately. Saves on shipping and total cost. Allows for customer preferred brand.

Master Cylinder Mount Kit

Master Cylinder Mounting Kit Details

Uses stock brake actuator rod coming from brake pedal.
Uses stock brake light switch mounted to crossmember.
Mounts to crossmember under front seats.
Mounts below crossmember behind battery.
Mounts below parking brake cross shaft.
Provides mechanical advantage of 1.3/1 (Stock pedal has 3.5/1 so total is 4.5/1).
Builders have used a1966/1967 Cadillac 1" bore master cylinder. This is a good choice but does not have a clear reservoir. (Hat tip: Taylor Made Motors in New Braunfels, Texas)

>>> New suggested master cylinder:

- Raybestos MC390525 or Dorman M390525

- This is a 1" bore with the translucent reservoir that mounts just like the originally suggest master cylinder except the ports face toward the Model A frame rail instead of toward the trailing arms.

- This master cylinder requires two adapter fittings to adapt from M10x1.0 metric bubble to 3/16" inverted flare (3/8-24 thread). (AGS# BLF-31C)

- You can also find short adapter tube with the metric M10x1.0 tube nut at one end and the 3/8-24 tube nut at the other. (AGS# BLA-0310) This allows you to run to an RPV directly and use the 3/16" tubing after that.

Secondary (originally) suggested master cylinder: Dorman M390398 (or equivalent).

-This is a 1-1/16" bore master cylinder used on a 2000 Ford Explorer 4-door.

-It has an translucent reservoir so you can see the fluid level without cutting a hole

in your floor.

This master cylinder will need the following fittings to adapt to 3/16" inverted flare brake lines: (Hat tip to TNT Customs in Cheyenne, WY)

-NAPA Auto Parts 641-3315 (BK6413315) or equivalent (AGS: BLF-33B)

Thread Sizes: 3/8"-24 Female Inverted Flare to M12x1.0 Male Bubble

-NAPA Auto Parts 641-5026 (BK6415026) or equivalent (AGS: BLF-31)

Thread Sizes: 3/8"-24 Female Inverted Flare to M10x1.0 Male Bubble

- NAPA Auto Parts G60691-0003 Brass Inverted Flare Plug (AGS: BLF-60B)

Thread Size: 3/8"-24 Inverted Flare Plug

Frequently Asked Questions

Please reach us at garrettengineering@gmail.com if you cannot find an answer to your question.

What else do I need to buy?

2X 2004 Kia Sorento REAR rotors. Used for both front and rear kits.
1X left and 1X right GM Metric brake calipers. Look up 1980 Chevy Malibu as an example.
1 set of semi-metallic brake pads for the GM Metric calipers.
Brake lines and master cylinder/MC mounting.
2X RPV (2 psi - residual pressure valves, 1 front circuit and 1 rear circuit), and an adjustable proportioning valve placed in the rear circuit.

(I ask the buyer to buy these parts separately to eliminate double shipping of heavy parts.) Also, the buyer may have a preference on sources/brands for these parts.

What size master cylinder do I need?

You will want a 1" bore master cylinder. You can try 1-1/16" or 15/16" bore.

Why change to hydraulic disc brakes?

While many in this hobby will never change from the stock mechanical drum brakes because the stock brakes will skid the tires and can be adjusted to provide very good braking, there are reasons that some people do want to change to hydraulic brakes.

Hydraulic disc brakes do not provide a huge increase in braking power so there are no surprises in braking performance.
Hydraulic disc brakes provide smooth, linear, even braking without constant adjustments.
Hydraulic brakes do not have the numerous parts that must be adjusted, replaced, filed, ground, riveted or assembled during a full moon to get good braking performance.

What brake hoses do I need?

Builders have used a wide variety of brake hoses when installing these kits including:

Front - 10mm Banjo Bolt X 3/8-24 inverted flare (3/16 tube) X 20-24 inches long

Front Caliper: NAPA part 609917 (2007-2017 Jeep Patriot)
Front Caliper: 1975 Chevrolet C10 pickup front (23± long)

Rear Caliper - 10mm Banjo Bolt X 3/8-24 inverted flare (3/16 tube) X 12-18 inches long

Rear Caliper: NAPA part 368417 (1979-1988 Chevrolet Monte Carlo)

Rear Center - Single 3/8-24 inverted flare(3/16 tube) X Double 3/8-24 inverted flare (3/16 tube)

Rear Center: NAPA part 36799 (1975-1975 Jeep CJ5)

Model A Disc Brakes - All the Stuff Dad Never Told You

Hydraulic Lines

Use 3/16" or 1/4" brake lines with these kits. The 3/16" brake lines are more available and the fittings are easier to find.
At each caliper you must have a length of flexible hose to connect from the caliper to the frame mounted brake lines. This allows removal of the caliper to change the pads and for the motion of the steering on the front axle.
In general, the brake lines to the front may be routed along the driver's side frame rail to a TEE near the driver's side front caliper, then across the front crossmember to the passenger side caliper.
The rear brake line may be attached to the forward end of the trailing arms with a flexible connection, then run down each trailing arm to the ends of the rear axle.
OR
The rear brake line may run along the frame rail to the rear axle and connected to a TEE on the rear axle using a longish flexible line. The long connection is to allow the rear axle a lot of motion relative to the frame/body. Then along the axle to each end.

Master Cylinder

These kits will work well with a 1" (±1/16") master cylinder bore.

If you are using a battery box mounted master cylinder, ask the supplier what bolt pattern it is made for.
If you are using a firewall mount, Wilwood, Tilton, Speedway Motors and others have matched master cylinders.
If you are building a custom mount under the floor, Chevy and Ford master cylinders are both popular.

Other Components that are IMPORTANT

A 2 psi RPV (residual pressure valve) is required if you are mounting the master cylinder under the floor. This will prevent brake fluid backflow into the master cylinder since the master cylinder ends up lower than the brake calipers. If you are running a tandem master cylinder, you will need one for the front circuit and one for the rear circuit. (Do not use a 10 psi RPV unless it is in a circuit for a drum brake.)
It is strongly suggested that you include an adjustable proportioning valve in the rear brake circuit. The proportioning valve reduces the pressure to the rear brakes and is adjusted to allow the front brakes to skid just before the rear brakes do for better control of the car.
These components are readily available from online suppliers like Speedway Motors, Summit Racing, Jegs, Pete and Jakes and others.

Contact Us

These Model A Disc Brake kits are for use with stock style wheels and tires (Model A, 1935 Ford)

If you are building a hot rod with wide/offset tires, you want to talk to one of several suppliers like Speedway Motors, Pete & Jakes or Posie's.

(Early wheels from 1928 will not work with the wire wheel spacers.)

Model A Disc Brakes

9893 Bradbury St, Firestone, CO 80504-5936

+1.303.727.0106

Hydraulic Disc Brake Kits for Front or Rear

Hydraulic Disc Brake Kits for Front or Rear