- The Washington Times - Thursday, July 28, 2005

Speed and agility are the qualities that carmakers boast about when they introduce a new sports sedan. As the benchmark in that segment, the 2006 BMW 3 Series has those characteristics in abundance.

What also distinguishes the new-generation 3 Series is the attention BMW engineers focused on giving the vehicle enhanced stopping capability thanks to innovative state-of-the-art brake systems.

New six-cylinder engines and an improved suspension improve the speedy and nimble performance of the 3 Series. BMW boasts about these engineering improvements that will do nothing to damage its claim to being the ultimate driving machine. But with its advanced braking systems this new 3 Series may also lay claim to the title of the ultimate stopping machine, too.

Enhanced brakes not only give the 3 Series quicker and surer stopping power, but also provide features that make driving safer and more enjoyable. The ventilated rear disc brakes in the 325i are bigger, going from 11.6 inches to 11.8 inches. Front discs in this model remain the same. In the 330i, front discs have been increased to 13 inches from 12.8 inches.

BMW’s engineers collaborated with Continental Teves in creating additional brake components that enable faster stopping and improve performance on wet roads, which sometimes make brakes less effective.

For instance, a new brake-drying feature eliminates delayed brake response by cleverly removing moisture from the brake discs. To accomplish this, the brake system gently presses the pads against the discs frequently. But the action is so gentle that you don’t notice it happening.

The result is that the discs build up less moisture and remain effective under adverse conditions. It means that the pads don’t have to cut through as much water to start gripping the disc. This time-saving is measured in millimeters, but that fraction of time may be enough to avoid an accident.

There’s also a brake pad wear detection system that calculates how much life remains in these components. The wear monitor constantly evaluates a range of parameters, giving adequate warning when it is time to replace the brake pad.

A brake fade compensation system resists the heat of panic stops that degrade the stopping abilities of most brake systems. Drivers need to apply more pressure to the brake pedal to maintain stopping action when this happens.

The new fade compensator increases the hydraulic system pressure to ensure that it is always adequate at each wheel to stop as quickly as the driver wants. There’s even a light on the instrument panel that illuminates when brake fade is possible.

However, there is little chance of brake fade in this system because aluminum front-wheel calipers are used for the first time in a vehicle in this segment. The front caliper brakes have extremely high reserves under stressful performance and temperature conditions.

Brake stand-by gives a driver more time to apply the brake pedal, because it builds up pressure in advance of initiating the stopping action. A sensor in the system recognizes when a driver gets off the gas pedal quickly and may start braking. The stand-by function preloads the brake system so that if braking actually begins it can occur with virtually no delay. If the brakes aren’t applied in a few seconds, the pressure returns to normal.

ABS brakes have an anti-lockup action that’s smoother when activated. A new “analogized” control of the dynamic stability control valves creates this improvement.

Although it’s hardly unique, the 3 Series also has the start-off assistant. This hill-hold device makes it easier to start up when you are stopped on a hill. The system maintains brake pressure for 1.5 seconds and releases it smoothly when you accelerate the car. It gives the driver ample time to engage the clutch and step on the accelerator without rolling backward.

The soft-stop feature of the brakes is a nice touch. It eliminates the small jolts that frequently occur even with the gentlest stops. The soft-stop feature eliminates the jolt by automatically releasing brake pressure at the last possible moment. When the component’s sensor recognizes that the vehicle is stopping, it signals the system to reduce rear-wheel brake pressure before a complete stop.

The result is a smooth stop that’s in keeping with the rest of the car’s smooth performance.



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