Braking Series..part 1:stop as fast as u can ..

Brakes dont get much attention until theyre worn and braking upgrades are the least understood among st enthusiasts . Although brake upgrades dont contribute to horsepower or torque gain, strong brakes are essential in the tuning process.The stock brakes may not be good be good enough if you increase horse power ,attend the occasional track day if you are an aggressive driver.

Operation-Modern cars are equipped with power assisted hydraulic braking systems.The system works first when flooring the brake pedal , which in turn applies force from the brake master cylinder tp the brake booster.This pressurizes the brake fluid in the brake lines which connects to the brake calipers.Brake pads

are held by the calipers,where in operation, are clamped against the rotors, by the action of the pistons, located in pots, inside the calipers. The rotors are connected to the axle on the wheels, which forces the wheels to stop by friction, when they are clamped by the pads.

Normal production cars normally feature ventilated disc rotors in the front wheels and drums at the rear wheels.The rear drum assembly consists of brake shoes instead of pads which are pushed outwards against the inner side of the drums unlike caliper that clamps onto their rotors.All brakes function by converting the kinetic energy of the car into thermal energy during deceleration , thus producing heat. The heat must then be transferred to the rotor mechanism and dissipate into the air stream.

Problem : heat is the primary cause of ineffective braking. The amount of heat produced in a braking system depends on the rate of work. The more heat the rotor can absorb and dissipate, the greater the efficiency of the system.The rotor dissipates approximately 80% of this energy.The ratio of heat transfer is dependent on the operating temperature of the system. Repeated hard stops require both effective heat transfer and adequate thermal storage capacity within the rotors.Our stock rotors and pads may be sufficient for normal driving, but as speed and brake demand increases, there is a need to upgrade.More over , the larger 17" or 18" rim and tyre upgrades have more rotating mass thereby stressing the now "smaller" stock rotors.

Imagine the additional weight to the now seemingly small stock rotors when bringing the car to a stop at speed.The stock rotors are relatively smaller in diameter and thinner hence get heat soak more easily than aftermarket performance rotors.When heat cannot be adequately and timely transferred , (overheated brake pads and rotors) coupled with the weight issue, you generally not only increasing stopping distance but a condition commonly called "brake fade" as well. Brake fade severely impairs braking performance by slowing brake response because the pedal feels spongy.ie more pedal travel - harder to modulate by the action of the foot.Brake fade is caused by a layer of hot gases which build up and gets trapped between brake pad and rotor surfaces.

Solution. By switching to an aftermarket big brake kit or upsized rotors, (diameter and thickness) heat can be dispersed more evenly throughout the rotor,thereby reducing the chance of heat soak and brake fade.The more rotor surface area per unit mass , the greater and more efficient the mass flow of air over and through the rotor, the faster the heat will dissipate-the more efficient the entire system will be. Moreover, the brake rotors must have enough thermal storage capacity to prevent distortion and/or cracking from thermal storage capacity to prevent distortion and/or cracking from thermal stress until the heat can be dissipated.This is not particularly important in a single stop but is crucial in repeated stops at high speed like maneuvering on a track.

Brake pedal: The brake pedal is designed to multiply the drivers' efforts. The stiffer and tighter the pedal the less force is transferred to the clamping system via the brake booster and master cylinder pump.The higher the pressure in the brake lines and more pedal travel you have, the more clamping force you have.Effective brake modulation therefore requires minimum pedal travel and maximum pedal firmness maintaining maximum retardation without locking wheels. The mechanical pedal ratio is the distance from the pedal pivot point to the effective centre of the footpad divided by the distance  from the pivot point to the master cylinder push rod.Typical ratios range  from 4:1 to 9:1 . The larger the ratio , the greater the force multiplication (and the longer the pedal travel). This ratio can be adjusted by a tuner.Effective brake modulation is necessary for controlling and keeping the car stable. and has nothing to do with braking efficiency or torque.There are aftermarket brake boosters (capsule/cylinder) some equipped with gauges that is said to assist brake modulation.

Braking system: Newer cars are mostly equipped with ABS (anti lock braking system) EBD (electronic brake force distribution) or BA (brake  assist) braking systems.An ABS system pumps the brakes automatically , many times a second, to prevent lock up which helps the driver maintain steering control and avoid skidding on the wet. On dry roads,ABS doesnt substantially shorten stopping distances. Drivers are traditionally taught to pump the brakes hard and fast on slippery roads to avoid skidding. But with ABS, firm and continuous pressure , not pumping is required to activate ABS feature.ABS drivers should not be alarmed by mechanical noises or pedal pulsations when applying brakes because these are indicative of a normal functioning system.ABS is only activated under hard braking, do not pump the brakes in an effort to avoid locking up the wheels because the system automatically pumps the brakes, much faster than you can.
Maintain firm and continuous pressure on the brake pedal when braking,even if the pedal pulsates.Do not allow enough distance to stop. Remember, ABS doesnt necessarily allow you to stop in a shorter distance,it only helps you to maintain directional control.It is said ABS is not recommended for rally use.

Conclusion. Hard driving , towing or carrying heavy loads place tremendous burden on your brakes. Under these conditions, stock brakes can reach abnormally high heat levels. The measure of an efficient braking system is tested from higher speeds, or during repeated heavy braking.The brakes should provide for maximum deceleration at speed, and the ability to absorb and quickly dissipate the intense heat generated during repeated braking. Absolute braking performance will also depend on the tires ability to provide traction, suspension stiffness and driving skills.These must be optimized in unison if your car were to stop on a dime.