Thumbnail for Two-piece Girodisc brake rotors with curved slots with black rotor hats and gold-colored hardware.

Thumbnail for Close-up image of a Girodisc 2-piece brake rotor viewed from the back

Two-piece Girodisc brake rotors with curved slots with black rotor hats and gold-colored hardware.

Close-up image of a Girodisc 2-piece brake rotor viewed from the back

A1-311 Girodisc Audi B9 S4, S5, SQ5 Front Rotors

These Girodisc A1-311 two-piece front rotors are a direct, bolt-on replacement for the B9 S4, S5, and SQ5. The fully floating design sheds unsprung weight and improves cooling versus OE one-piece rotors while retaining factory calipers, ABS, and brake bias.

Vehicle Fitment

Audi S4 (B9) – Front
Audi S5 (B9) – Front
Audi SQ5 (B9) – Front

High-Carbon Rings, Curved Vanes

Proprietary high-carbon iron rings use curved internal vanes to draw cooling air through the disc. Reusable 6061-T6 aluminum hats and cadmium-plated drive pins control thermal growth and maintain quiet street manners.

Features

Direct OE replacement; no mods required
Two-piece floating design reduces unsprung weight
High-carbon iron rings with curved vane cooling
Reusable aluminum hats; new hardware included
Manufactured and assembled in Bellingham, WA

A1-311 FAQs

Pad compatibility? Works with OE or performance pad compounds.

Bed-in needed? Yes—perform a standard bedding procedure after install.

Front ring part number? D1-311 front replacement rings.

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