How Saab brakes, clutch put engine power at your feet
The transmission and brake systems of the Saab are key in keeping a tight rein of the car’s engine power. Composed of a Saab brake rotor, brake pads, and hydraulic brake assembly, the Saab brake system is what retards the motion of the vehicle, while the Saab clutch, flywheel, and transmission line are collectively the drivetrain parts of the Saab that controls power flow from the engine to the wheels. At a step on the pedal, the Saab clutch and brakes put engine power at the driver’s feet.
Most Saab automobiles use a disc brake system. It works on the principle of a caliper tightening on a rotating disc. Called Saab brake rotor, the brake disc is mounted on the wheel and provides a clamping surface for the brake pads and the caliper during brake operations. In a step on the brake pedal, the foot pressure is transferred hydraulically to the calipers, which then cleave to the Saab rotor and retard the motion of the car.
Operationally, brake discs are exposed to high-heat condition. Most Saab brake rotors are made of cast iron and designed to withstand the heat and friction against the brake pads. As a failsafe to heat buildup, Saab brake rotors sport heat vents, ranging from slotted contact surface, to cross-drilled, and finned finishes. These vents help dissipate gas and heat out of the Saab brakes assembly, preventing the rotor from warping and reshape the disc.
Heat buildup between the Saab brake rotors and the pads can cause thickness variations. When this happens you get a pedal pulsation, sometimes a jolt in the steering wheel, too, and brake fade. Brake rotors do not usually get thin and wear out, but rather lose the heat ventilations on their contact surface. It is common practice to turn a brake rotor to mitigate the effects of heat, but this practice has been found to contribute more on rotor thickness variations.
The Saab transmission system part, on the other hand, most responsible in car handling is the clutch assembly, a mechanism for transmitting rotation. Essentially, the Saab clutch kit enables engine motion to be transferred to the drive wheels through the transmission’s gear system. A manual transmission contains cogs, which have matching teeth called dog teeth for selecting gears. Thus, the rotation speeds of the two parts must be synchronized for engagement. This process of speed matching is achieved by a secondary clutch called a synchromesh, a device that uses frictional contact to bring the two parts to the same speed, and a locking mechanism called a blocker ring to prevent engagement of the teeth (full movement of the shift lever into gear) until the speeds are properly calibrated.
There are various Saab clutch designs with the majority of them based on one or more friction discs, pressed tightly together or against a flywheel using springs. This friction material is similar to those used in brake shoes and pads and usually contained asbestos. The clutch is operated by the left-most pedal through the use of hydraulics or a cable connection from the pedal to the clutch mechanism. To eliminate the effect of slight engine movement and for easier operation, the Saab clutch is usually located near the pedal.
Both the Saab brakes and clutch are integral parts of the Saab drivetrain. They are directly involved in car handling operations and in streamlining the horsepower from the Saab engine. To obtain the proper system, a complete verification and qualification of the Saab vehicle, not only by its make and model year, but also define its intended use, is often applied to the Saab before tweaking its transmission and brake systems.
Written by Car Enthusiast on May 24th, 2007 with
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