Anti-lock braking system ... what is it?
I had a recent conversation with a young car guy who just started racing in Manila. He was using a daily driven Toyota Yaris, slightly modified with a roll cage, with added safety equipment and a stiffer suspension for more stable cornering. Everything else was bone-stock.
He asked me why the brakes on his car, which are exactly the same as our Toyota Vios Racecars, are not that responsive and that the ABS activates most often, taking out his confidence in attacking the corners of the racetrack.
I told him that to answer the question, we must first understand what an ABS is and how it works.
ABS, or Anti-lock Braking System was designed to help the driver maintain some steering ability under heavy braking and avoid skidding or plowing the car straight.
ABS was introduced in the mid -1980s and has become "standard" equipment on the majority of vehicles sold in the Philippines in the late 90s. This system was not invented for racing, but instead, for safety on the road. This system lets you steer while taking evasive action with directional stability, while maximizing braking.
How does it work?
ABS allows you to maintain control of the vehicle under sudden, forceful braking. Since ABS prevents all wheels from skidding, it allows you to steer the vehicle and still maintain braking. ABS uses sensors attached to the wheels, measuring the rotation or speed of each wheel. The Electronic Computer Unit in the car will then decipher if one or more wheels are trying to lock up during braking. If a wheel tries to lock up, a series of hydraulic valves reduce the braking on that wheel. This prevents skidding and allows you to maintain steering control.The drawback to this system is that the "feel" of the brake pedal is direct as the computer overrides your foot once the system is activated.
ABS is essential on the road
If you demand steering while braking, the 100 percent of traction that the tire can generate will be divided between both tasks. For example, if you require 50 percent for steering then there is 50 percent of available traction left for braking. If you require 10 percent for steering then there is 90 percent left for braking. Be aware that 100 percent traction on a dry road is a great deal more traction than 100 percent traction on wet surface! Therefore, your vehicle is unable to steer and brake as well on a slippery surface as it can on a dry road. This is where the ABS is most useful.
I can't say the same for a racecar with an ABS system. In a racecar, everything has to be direct. ABS takes out the braking "feel" of the driver, thereby giving him less confidence in attacking a corner. Although some sportscars do have advance braking systems designed for performance use and equipped with ABS, generally ABS is designed for road cars.
So let's put it this way, ABS is an essential system for the road and not really ideal if you go racing with it.
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