GiroDisc A2-049B 2pc Rear Rotors 350mm Porsche 981 Spyder 718 GTS 4.0 USA

Vehicle Fitment

• 2013-2016 Porsche 981 Boxster Spyder
• 2020+ Porsche 718 Boxster GTS 4.0 (982)
• 2020+ Porsche 718 Cayman GTS 4.0 (982C)

Fitment Notes

• This is an upgrade to 350mm diameter rear rotors - larger than the OEM rear disc; caliper spacers and longer caliper bolts are included in the kit to accommodate the larger diameter
• Compatible with factory OEM rear calipers - no caliper modification required
• Pad note: GiroDisc recommends using the Porsche 991 Carrera S / 4S / GTS rear brake pad shape for full pad sweep across the larger rotor surface
• Maintains factory brake bias and ABS functionality
• Sold as a pair (two rear rotors)

Features

• Two-piece fully floating design separates the 6061-T6 aluminum hat from the cast iron disc ring - prevents thermal warping, reduces pad knockback, and allows the rotor to self-center between the pads
• GiroDisc proprietary high-carbon cast iron disc rings poured in the USA and machined entirely in-house at GiroDisc - same material specification used by professional racing organizations
• Curved directional vane design acts as a centrifugal pump during braking, actively drawing cooling air through the disc to reduce heat buildup and brake fade under sustained track loads
• 10 cadmium-plated high-strength alloy steel drive pins secured by class 12.9 cap screws with hardened washers - transfer braking torque while maintaining full axial and radial float between hat and disc
• Anti-noise spring washers allow the disc to expand freely under heat while eliminating cold-weather rattle associated with floating rotors
• Typically 4-8 lbs lighter per rotor than the OEM unit - reduces unsprung and rotational mass for improved acceleration, steering response, and suspension dynamics
• Fully rebuildable - replace only the cast iron disc rings when worn; retain aluminum hats and hardware for multiple service cycles
• Includes caliper spacers and longer caliper bolts for a complete, direct bolt-on installation
• Made in the USA using domestically sourced materials

Specifications

• Part Number: A2-049B
• Brand: GiroDisc
• Position: Rear
• Rotor Type: Two-Piece Floating
• Diameter: 350mm (upgrade size)
• Vane Design: Curved Directional Vanes
• Hat Material: 6061-T6 Aluminum (Black Anodized), USA-sourced
• Disc Material: GiroDisc Proprietary High-Carbon Cast Iron, USA-made
• Drive Pins: 10 High-Strength Alloy Steel, Cadmium-Plated (Class 12.9 hardware)
• Required Pad Shape: Porsche 991 Carrera S / 4S / GTS rear (for full pad sweep)
• Country of Origin: USA (domestically sourced materials)
• Sold As: Pair (2 rear rotors)

Included Components

• 2x GiroDisc Two-Piece Floating Rear Rotors (A2-049B, 350mm)
• Caliper spacers and longer caliper bolts for installation
• Drive pins, class 12.9 cap screws, hardened washers, and anti-noise spring washers pre-installed

Product Description

The GiroDisc A2-049B is a two-piece floating rear rotor set designed for the Porsche 981 Boxster Spyder and 718 GTS 4.0 / Cayman GTS 4.0 - the high-performance open-air variants of Porsche's mid-engine sports car lineup. This kit upgrades the rear rotors to a larger 350mm diameter, providing increased swept area and greater thermal mass than the OEM disc. Caliper spacers and longer bolts are included for a direct, no-modification installation that retains full compatibility with the OEM rear calipers, ABS system, and factory brake balance.

GiroDisc's two-piece floating architecture pairs a lightweight 6061-T6 aluminum hat with the proprietary high-carbon cast iron disc ring through a 10-pin cadmium-plated floating mount system. This allows the ring to thermally expand independently of the hat, eliminating the warping and pad knockback that plagues conventional one-piece OEM rotors during sustained track use. Curved directional vanes inside the disc ring actively pump cooling air through the rotor during braking, keeping temperatures in check across both street and circuit environments. To achieve full pad sweep across the larger rotor surface, GiroDisc recommends using the Porsche 991 Carrera S / 4S / GTS rear pad shape. Sold as a pair; fully rebuildable with replacement rings available separately. Made entirely in the USA.