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Girodisc Audi with Brembo 18Z Front Replacement Rings

D1-309 are rings only, sold in pairs with new hardware. Reuse your existing Girodisc aluminum hats. These rings are engineered exclusively for Girodisc hats and are not compatible with OE or other aftermarket hats.

Vehicle Fitment

Audi S4 (B5) – Front, with Brembo 18Z caliper conversion (for A1-309 kits)
Audi A6 (C5) 2.7T – Front, with Brembo 18Z caliper conversion (for A1-309 kits)
Audi Allroad (C5) 2.7T – Front, with Brembo 18Z caliper conversion (for A1-309 kits)

Fitment note: These replacement rings are for Girodisc hats only.

Cost-Effective Service

High-carbon iron rings with curved vanes maintain cooling performance and thermal stability under repeated stops. New drive pins, clips, and Belleville washers restore the floating interface and clamp force.

Features

Replacement rings only; includes fresh hardware
Direct fit for Girodisc A1-309 front rotor kits
High-carbon iron; USA-poured and machined
Curved vane internal design for airflow
Sold/priced per pair

D1-309 FAQs

When should rings be replaced? At Girodisc’s service thickness or if a crack propagates to the outer edge.

Do I need to re-bed pads? Yes — perform a proper bed-in after ring replacement.

Torque specs? Use the torque/sequence included with the ring hardware kit.

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