Brakes

Pedal Rail Assembly

 

Features
Dual hydraulic circuit with twin Wilwood 3/4” bore master cylinders complete with fluid reserves and return springs.
Custom built adjustable pedal rail assembly designed to adjust fore and aft 7”
Two rotors of sizes 7.375 by 0.177 inches in the front and two rotors of sizes 7 by 0.125 inches in the rear and made of flat ground, air quenched steel.
Radially mounted dual 32mm piston Brembo Caliper at each wheel
Proportioning valve in rear brake line for fine tuning bias adjustment.
SBS 519 Dual Carbon brake pads for high temperature performance
3/16” steel brake line for interior hard line and six 3/16” steel flex lines.

 

 

Rule #
Rule
Analysis
7.1

It must have two independent hydraulic circuits such that in the case of a leak or failure at any point in the system, effective braking power is maintained on at least two wheels. Each hydraulic circuit must have its own fluid reserve, either by the use of separate reservoirs or
by the use of a dammed, OEM-style reservoir.

 

A single brake acting on a limited-slip differential is acceptable.

 

The brake system must be capable of locking all four (4) wheels during the test specified in Rule 7.2.

 

“Brake-by-wire” systems are prohibited.

 

Unarmored plastic brake lines are prohibited.

 

The braking systems must be protected with scatter shields from failure of the drive train (see 8.13) or from minor collisions.

 

In side view no portion of the brake system that is mounted on the sprung part of the car can project below the lower surface of the frame or the monocoque, whichever is applicable.

The car must be able to stop all four wheels by use of a single control. This can be done using conventional brakes on each wheel, or by use of a single brake on a limited slip differential. Braking by the use of a wire is prohibited. We will be using the conventional hydraulic disk brakes at each wheel for this years formula car.

 

The hydraulic circuits described in article 7.1.1 will be two Girling master cylinders, each of which has its own fluid reservoir. One master cylinder will control the pressure to the front calipers and the other to the rear calipers.

 

For brake protection plastic brake lines are prohibited, and the brake lines must be protected from the drive train in case of failure. If the drive train fails and “shatters” the brake lines must be protected to prevent brake failures. The brake lines must also be above the lowest part of the frame. Our lines are mounted directly under the cockpit and above the lower frame bar. This keeps the lines out of sight and protected from small collisions and shrapnel. The chain scatter shield will also be designed to protect the brake lines in case of chain failure.

7.2 The brake system will be dynamically tested and must demonstrate the capability of locking all four (4) wheels and stopping the vehicle in a straight line at the end of an acceleration run specified by the brake inspectors.  
7.3

A brake pedal over-travel switch must be installed on the car. This switch must be installed so that in the event of brake system failure such that the brake pedal over travels, the switch will be activated and will stop the engine from running. This switch must kill the ignition and cut the power to any electrical fuel pumps.

 

Repeated actuation of the switch must not restore power to these components, and it must be designed so that the driver cannot reset it.

 

The switch must be implemented with analog components, and not through recourse to programmable logic controllers, engine control units, or similar functioning digital controllers.

The brake system is one of the most important safety features on the formula car. In case of brake failure there must be a second feature for emergency stopping. The rules call for an emergency switch placed behind the brake pedal. In case of brake system failure the pedal will travel further than normal and will actuate the switch. This switch will cut power to the engine, and to any electrical fuel pumps. The switch will be further analyzed in the electrical subsystem.

7.4

The car must be equipped with a red brake light of at least 15 watts, or equivalent, clearly visible from the rear. If an LED brake light is used, it must be clearly visible in very bright sunlight.

 

This light must be mounted between the wheel centerline and driver’s shoulder level vertically and approximately on vehicle centerline laterally.

Also needed is a single brake light in the rear of the car. We currently have an LED brake light.

 

Brake System Specifications

Front

Rear

Rotors

Hub mounted, 0.178 inch x 7.3 inch,  4130 HR steel

Hub mounted, 0.125 inch x 7.3 inch, 4130 HR steel

Master Cylinder

 Wilwood 0.75 inch bore diameter master cylinders with fluid reserve and piston return spring.

Calipers

Brembo P32F, opposing piston, 32mm bore

Brembo P32F, opposing piston, 32mm bore

Ergonomics

Driver Size Adjustments

Sliding pedal rail