1967–1970 Ford Mustang Slim Line Power Brake Booster Conversion Kit for Automatics (Disc/Disc)

1967–1970 Mustang · Automatic Transmission · 4-Wheel Disc ·

9" Slim Line Black Booster · Master · Pedal, Valve & Lines Included · 100% New Parts

At a glance:

• ✔ Slim line 9" power brake booster, black, with firewall plate
• ✔ Built for 4-wheel disc (disc/disc) brake systems
• ✔ Manual-to-power conversion, or a brand-new replacement for factory power brake cars
• ✔ Designed specifically for 1967–1970 Mustangs with automatic transmissions
• ✔ 1" bore master cylinder with the correct 2227161 "teardrop" casting
• ✔ Power brake pedal, disc/disc proportioning valve, pre-bent lines, and hardware included
• ✔ Every part is brand new. No remanufactured parts, ever.
• ✔ Free tech support: 866-601-4455

Running four-wheel discs on your Mustang? Then your brakes deserve power assist that's set up for them. This complete slim line power brake booster kit converts your 1967–1970 automatic from manual to power-assisted disc/disc brakes for a lighter pedal and confident, controlled stops. Already have factory power brakes? It's also the perfect brand-new replacement for a tired original booster and master.

Everything is engineered to work together, from the 9" slim line booster and the 1" bore master cylinder with the correct-looking 2227161 teardrop casting to the power brake pedal, disc/disc proportioning valve, and pre-bent lines. And unlike kits built from rebuilt cores, every part in this kit is brand new.

What's Included

Slim Line Power Brake Components

• 9" Slim Line Black Mustang Power Brake Booster with Firewall Plate
• 1" Bore Master Cylinder, 2227161 casting number with "teardrop" markings
• Power Brake Pedal with Pedal Pad
• Mounting Hardware

Proportioning Valve & Plumbing

• Bottom-Mount Disc/Disc Proportioning Valve Kit
• Zinc Bottom-Mount Valve Bracket
• Pre-Bent Brake Lines to Master Cylinder

Specifications

Why Buy This Kit

• ✔ Set up for 4-wheel disc: the disc/disc proportioning valve is matched to your brake system
• ✔ Slim line booster: a compact 9" booster that fits the classic Mustang engine bay
• ✔ Complete conversion: booster, master, pedal, valve, lines, and hardware in one box
• ✔ Lighter, easier pedal with power assist
• ✔ Period-correct look: the 2227161 teardrop casting looks right under a classic Mustang hood
• ✔ Power brake pedal included, so there's no need to hunt down a used one
• ✔ Pre-bent lines from the valve to the master cylinder save you time
• ✔ All new, never reman: no worn cores, no surprises

Shopping for a LEED Brakes 03473? Compare Before You Buy

If you're looking at the LEED Brakes 03473 kit for your 1967–1970 Mustang automatic with 4-wheel disc brakes, here's how our slim line kit stacks up:

LEED Brakes and 03473 are trademarks and part numbers of their owner and are used here for comparison only. Competitor details are based on publicly listed product information and may change.

Fitment

Don't see your car? Call us at 866-601-4455 before ordering.

Before You Order: Please Read

Automatic Transmission Only
This slim line booster kit is designed for 1967–1970 Mustangs with automatic transmissions.

Disc/Disc Brakes Only
This kit is set up for 4-wheel disc brake systems. Running front disc and rear drum? Order our disc/drum version of this kit instead.

Brake Line Connections
The pre-bent lines connect the proportioning valve to the master cylinder. Your lines to the front and rear brakes connect at the valve.

⚠️ Installation Notes

• Master cylinder: Bench bleed the master cylinder before installing it. Use fresh DOT 3 or DOT 4 brake fluid.
• Vacuum source: Connect the slim line booster to a manifold vacuum source.
• Bleed the system: Bleed all four wheels, then check every fitting for leaks.
• Test drive: Test the brakes at low speed in a safe area before driving.

Free Tech Support

Every kit comes with free tech support before and after your purchase.

• Call: 866-601-4455
• Monday–Friday, 8:00 AM – 4:00 PM EST
• Limited weekend availability

We're happy to help make sure this kit is right for your Mustang.

Slim line power for your 4-wheel disc Mustang. All new parts. Order your slim line booster kit today!

Questions? Call 866-601-4455