Brakes

 Brakes are one of the most important performance upgrades you can make to a car. Your car's brake performance must match it's power and handling for the car to be competitive. There is no point being the fastest car on the road or track and when you need the brakes to stop, you can't make the turn. 

Normally Performance Brake upgrades would come in different stages, including uprating the brake pad material and using larger ventilated tow-piece disc/rotors. Also steel braided brake lines, larger calipers and different Brake pad materials are a few of the options available. Braking systems are a integral part of a good performance package and there a lot of effective products out there.

The Disc brakes which causes the wheels to stop rotating are a device mounted normally on each wheel axle and we will only cover this type rather then drum brakes (low performance potential and considered primitive technology).

A brake disc/rotor can be made of cast iron or ceramic composites (including carbon, kevlar and silica). This is all in an attempt to reduce brake fade and increase stopping power.

It is connected directly to the wheel or the axle and to stop the wheel rotating, friction material called brake pads (mounted on a brake caliper and activated via pistons).These can be forced mechanically, hydraulically, pneumatically or electromagnetically against both sides of the disc.This friction causes the disc and attached wheel to slow or stop and this process generates high brake temperatures and in many high performance applications you will see the disc glowing amber.

 Normally in high performance car models this has been engineered into the equation, but like most things which are sold; evething has a mark up and budget. By using a combination of different materials you can effective increase braking performance significantly. Especially on less expensive, mass produced car models.

 ABS

In a emergency driving situation, you need the brakes to work as quickly and as effectively as possible, at maximum capacity.  This is where ABS (Anti locking braking sytem) can make the difference between a fatal accident or a near miss.

In the old days when you applied too much brake pressure on the pedal, the road tyres/tires grip levels would be exceeded. This in turn would result in the wheel locking up and up to 30% of the maximum braking capacity of the car could be reduced. Also all the turning inputs of the steering wheel would be pointless due to the fact of the tyres/tires already pass their performance limit. In any one time a tyre/tire can only have a certain percentage of acceleration, braking and turning. This is referrred to as the traction circle. When maximum braking is deployed in a straight line,it is referred to as Threshold Braking.

The only way of returning the full braking efficeincy is to release some of the brake pedal pressure, this will unlock the wheels and regain maximum braking effort. Also further release of the brake pedal will return more and more of the turning ability of the car. 

An old technique called Cadence braking involved pumping the pedal and simultaneously turning the steering wheel. This technique is made mainly redundant in modern cars due to the introduction of ABS braking systems. When ABS is activated sensors in the wheel will stop the tires/tyres locking up, also the amount of turning percentage required is modulated with steering will imputs. It is normal to hear a differnt noise from the wheels under ABS operating conditions, also there may be a pulsing or vibration from the brake pedal.

 Brake Bias

A car's level of grip and it's attitude under weight transfer from heavy deceleration affects the brake balance of the car. As you increase the performance of a car, you may need to adjust brake balance to maximise braking effort. Also to rebalance the Understeer and Oversteer equilibrium to maximise performance upgrades.

By controlling the relative distibution of hydraulic pressure between the front and rear brakes, you can affect tyre/tire lock up (both front and rear). Adjusting rear brake bias will induce oversteer and decrease stability. Adjusting the front bias will promote Understeer and stability. So care must be taken to get the desire handling characteristics. The front brakes do most of the work in production braking systems and a 60:40 front bias is the norm, so only small adjustments should be make to try and get all four wheels locking up at the same time. Which is the ultimate aim.

 Regenative Braking 

In the world of automobiles, the faster you want to accelerate; the more power is required to overcome the air resistance and drag. Regentative braking is a way to save and store some of these energies used to move the car. 

In a conventional (or electrical) vehical torque is required to move the wheels and frictional losses causes inefficeintcies. The same losses occur when you apply the brakes and this energy is converted from movement to heat to aid the car to slow down. It is a lose-lose situation and is essentially a efficient technological set up. Regenative braking can help to keep these losses to a minimum and can even help to increase fuel efficiency. With greener and more effective braking systems being adopted, the future of the car doesn't look so bleak,

We have seen a more wide application in these technologies in the automotive world with cars like the Toyota Pruis. I suppose this is just the start for these Innovations in the General Automotive world and even Motorsports. Take F1 for example, plans to reuse some of this wasted losses and further increase the performance are currently underway. 

Strangely the Turbo charger was originally a aeronautical device designed for this purpose,utilising otherwise wasted energy. Now it is a widely adopted technology and became very popular in the 80's both in Motorsport and production cars.