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

A2-322 Girodisc BMW G8X M3, M4 Rear Iron Rotor Conversion

Price: $1,350.00

These Girodisc A2-322 2-piece rotors convert the rear 380 mm CCB setup on G8X M3/M4 to high-carbon iron while retaining the OEM CCB calipers. No permanent mods — swap rotors and run the factory iron pad shape for the rear calipers.

Vehicle Fitment

BMW G80/G81 M3 with CCB – Rear
BMW G82/G83 M4 with CCB – Rear

Built for Heat, Quiet on the Street

High-carbon iron rings with curved vanes act as a centrifugal pump to move air through the disc for consistent temperatures. Spring-preloaded floating hardware allows thermal growth without the rattle of loose float systems.

Features

Direct CCB-to-iron conversion; no coding required
2-piece floating construction reduces unsprung/rotational mass
Curved-vane rings for efficient cooling
Reusable aluminum hats; cadmium-plated pins
Manufactured and assembled in Bellingham, WA
Sold/priced per pair

A2-322 FAQs

Which pads do I need? Use the factory iron rear pad shape for the G8X CCB calipers.

Parking brake compatibility? Fully compatible; the hat offset maintains OE parking brake operation.

Rear rotor size with this kit? 380 mm, matching the CCB system diameter.

Minimum service thickness? Replace rear rings at 26 mm or sooner if a crack reaches the ring edge.

Which rear rings match later? D2-322.

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