Barracuda Brake System
This page will present information about the brake system on the Barracuda.My Barracuda is a factory manual brake car with 11" disc brakes on the front and 10" drums on the rear. The original front brake rotors and 4 piston calipers were made by a company called Kelsey-Hayes. Kelsey-Hayes also made disc brakes for '65 to '67 Mustangs and as a result my car uses the same front brake pads as an early Mustang.
In its original configuration my car had horrible braking performance. The brakes required a tremendous amount of pedal pressure and would lock up the rear wheels on any type of aggressive stopping. This was a very dangerous set up and a well known problem on these cars. The brakes were like this when these cars were new back in 1969.
After lots of research and trial and error I finally got the brakes working like they should on a high performance car. The following modifications have been made:
- 7/8" rear wheel cylinders (originals were 15/16")
- 15/16" bore size master cylinder (original was 1")
- Goodridge G-Stop braided steel flex hose kit (original was rubber)
- Mopar Performance adjustable proportioning valve
- EBC Red Stuff front brake pads
In addition to the above modifications all the brake system components have been replaced with new over the years. This includes new rotors, new calipers, new rear brake drums, all new rear brake components, and all the steel brake lines that mount to the chassis have been replaced.
Rear Wheel Cylinders
The smaller 7/8" bore rear wheel cylinders apply less pressure to the rear brake shoes. I ordered the wheel cylinders for the rear of a '72 Dodge D100 2WD truck and they are a direct bolt on in place of the original 15/16" units. The swap to the 7/8" wheel cylinders greatly reduced rear wheel lock up.Master Cylinder
The smaller bore 15/16" master cylinder applies greater brake line pressure to the entire brake system with less leg effort. It does cause more travel in the brake pedal which does not cause problems. Being the car is manual brakes less pedal effort is a major plus. I ordered the master cylinder for a '73 Duster 340 with power disc brakes and it was a direct bolt on to my manual disc brake car.Goodridge G-Stop Braided Hoses
The braided brake hoses eliminate the tendency the original rubber hoses had of expanding when pressure is applied to the brake system. The expanding of the rubber hoses reduces the brake pressure that is applied to the wheels. The Goodridge kit part number is 12421. The kit had two front hoses and one for the rear and fit without modifications.Proportioning Vavle
This car did not have a proportioning valve from the factory. Generally a front disc/rear drum brake car should have a proportioning valve so that more line pressure is applied to the front brakes. The proportioning valve is installed on the frame rail in the brake line that runs to the rear of the car. By adjusting the valve less pressure is sent to the rear of the car for more balancing braking.EBC Brake Pads
The front brake pads were upgraded to EBC Red Stuff ceramic pads. Ceramic pads have less dust, make less noise, and do not fade when hot like the original pads did. The ceramic pads also have significantly greater grip on the brake rotors which allows the car to stop faster with less pedal effort.System Performance
In the original configuration I had to be careful and allow a lot distance to other cars because the car simply would not stop quickly. As a result of the brake system modifications the car can easily lock the wheels up without a lot of pedal effort for very quick stops. When just driving the car in normal traffic conditions the brakes stop with confidence without a lot of leg pressure.
