What is the size of the original brake discs for the Audi S3?
2 Answers
The original brake discs for the Audi S3 are 345mm in size. Introduction to brake discs: A brake disc is a round disc that rotates when the car moves. The brake caliper clamps the brake disc to generate braking force, slowing down or stopping the car when the brakes are applied. Brake discs provide effective braking performance and are easier to maintain compared to drum brakes. Function of brake discs: Brake discs are used for braking, with the braking force coming from the brake caliper. Typically, standard brake calipers have a fixed inner piston pump, while the outer part is a clamp-like structure. The inner brake pad is fixed to the piston pump, and the outer brake pad is fixed to the outer part of the caliper. The piston is pushed by the pressure from the brake fluid line, moving the inner brake pad, while the reaction force pulls the caliper, bringing the outer brake pad inward. Both pads press against the brake disc, generating braking force through friction between the disc and the pads. In this process, the piston is actuated by brake fluid, also known as hydraulic oil.
As a seasoned Audi enthusiast, I remember my S3's original front brake discs were 340mm in diameter, about 28mm thick, and the rear ones were 310mm. This size is sufficient for daily driving, providing smooth and responsive braking for city commutes. However, on the track or mountain roads with aggressive braking, they tend to overheat easily, making annoying hissing sounds. I later upgraded to larger 355mm discs with performance pads, which significantly improved heat capacity. When changing discs, remember not to skimp on matching the discs and pads, and check for caliper looseness to avoid noise. Regularly measure the thickness every 20,000 km; replace them if they're thinner than 24mm. Wheel size greatly affects disc selection—17 inches or larger is ideal for upgrading factory discs with ample potential, making the driving experience exhilarating.
