GiroDisc GD355.32.52 Replacement Rotor Rings 355x32mm for Brembo/StopTech BBK

Vehicle Fitment

• Universal -- any Brembo, StopTech, or Alcon BBK using 355x32mm rotors with 52mm annulus (including BMW and other platforms)
• 1994-1999 Ferrari F355 Challenge (front and rear -- 355mm OE)
• 1999-2005 Ferrari 360 Challenge (front -- 355mm OE)
• 1997-2002 Audi B5 S4 (with Stasis/Alcon or StopTech 355x32mm BBK)
• 1997-2004 Audi C5 A6/Allroad (with Alcon or StopTech 355x32mm BBK)
• 2002-2005 Audi B6 A4/S4 (with Alcon or StopTech 355x32mm BBK)
• 2005-2008 Audi B7 A4/S4 (with Alcon or StopTech 355x32mm BBK)
• 2009-2016 Audi B8 S4 (with Brembo or StopTech 355x32mm BBK)
• 2006-2020 Audi R8 (with Brembo or StopTech 355x32mm BBK)

Fitment Notes

• Replacement rotor rings only -- not a complete rotor assembly
• Bolts directly to existing OE or BBK rotor hat -- no modifications necessary
• Works with OE hardware, calipers, and pads
• Verify 355mm diameter, 32mm thickness, and 52mm annulus match your rotor hat
• Also compatible with Stasis/Alcon replacement assemblies
• Sold as a pair with 2 hardware kits
• Rings can be sent to GiroDisc for hat reassembly if preferred
• Always confirm compatibility with your specific BBK or OE application

Features

• Curved vane design -- acts as centrifugal pump to force cooling air through disc
• Slotted rotor face for gas evacuation and pad surface refresh
• Cast iron construction -- same specification and material used by professional racing organizations
• Full floating design for improved pedal feel and modulation
• Reduces unsprung weight vs. OE one-piece rotors
• Increased ventilation and cooling capacity
• Less than .0015" runout / less than .0003" disc thickness variation
• Engineered and machined in Bellingham, WA from US-sourced materials

Specifications

• Rotor Diameter: 355mm
• Rotor Thickness: 32mm
• Annulus: 52mm (D52)
• Rotor Type: Slotted, curved vane, vented
• Material: Cast iron (US-sourced)
• Runout Tolerance: <.0015"
• Disc Thickness Variation: <.0003"
• Compatible BBK Brands: Brembo, StopTech, Alcon, Stasis
• Sold As: Pair (2 rings + 2 hardware kits)
• Made in USA (Bellingham, WA)

Included Components

• 2x GiroDisc 355x32mm slotted replacement rotor rings
• 2x Hardware kits with floating pins
• Reassembly instructions

Product Description

The GiroDisc GD355.32.52 is a pair of 355x32mm slotted replacement rotor rings with a 52mm annulus (D52) designed as direct replacements for a wide range of OE and aftermarket big brake kit applications. Confirmed fitments include the Ferrari F355 Challenge (front and rear), Ferrari 360 Challenge (front), and multiple Audi platforms -- B5 S4, B6/B7 A4/S4, C5 A6/Allroad, B8 S4, and R8 -- equipped with Stasis/Alcon, Brembo, or StopTech 355x32mm big brake kits. Also compatible with any Brembo, StopTech, or Alcon BBK setup on BMW or other platforms using the 355x32mm rotor dimension and 52mm annulus. Rings bolt directly to the existing rotor hat using OE hardware with no modifications necessary, retaining full compatibility with existing calipers and pads.

The curved vane design was developed in professional racing to act as a centrifugal pump, channeling cooling air through the disc for superior heat dissipation under repeated heavy braking. The full floating two-piece construction improves pedal feel and modulation while reducing unsprung weight compared to factory one-piece rotors. Manufactured from US-sourced cast iron to the same specification used by professional racing organizations at GiroDisc's facility in Bellingham, WA, with tolerances held to less than .0015" runout and less than .0003" disc thickness variation. Sold as a pair with two complete hardware kits and reassembly instructions. Rings can also be sent to GiroDisc for professional hat reassembly if preferred. Founded in 2003, GiroDisc specializes in high-quality two-piece brake rotors for street and racing applications.