GiroDisc A1-203 350mm Front Big Brake Upgrade – 991.2 Carrera / 718 S / 992.1 Carrera

Description

GiroDisc A1-203 – Porsche 911 Carrera/C4/T (991.2) 350mm

The GiroDisc A1-203 350mm Front Big Brake Upgrade increases compatible factory front brakes from 330mm to 350mm on select Porsche 991.2 Carrera, 718 S and 992.1 Carrera applications. The kit retains compatible factory calipers using the supplied caliper spacers and mounting bolts, making it an alternative to a complete aftermarket caliper-and-rotor big brake kit.

Vehicle Applications and Fitment

• Porsche 911 Carrera / Carrera 4 (991.2) with 330mm front brakes
• Porsche 911 Carrera T (991.2) with the applicable 330mm front brakes
• Porsche 718 Boxster S / Cayman S (982) with compatible 330mm front brakes
• Porsche 911 Carrera (992.1) with compatible 330mm front brakes

Fitment note: This is a true big brake rotor upgrade: 350mm discs replace compatible 330mm factory front rotors. The 20mm increase provides a larger effective braking radius, while keeping the compatible factory calipers.

Brake System and Installation

Application-specific caliper spacers and mounting bolts are included for the intended 330mm-to-350mm conversion.

Two-Piece Floating Construction

GiroDisc combines slotted cast-iron friction rings with aluminum mounting hats and floating drive hardware. This arrangement accommodates heat-related expansion of the friction ring relative to the hat during repeated braking. The system is serviceable: worn friction rings can be replaced separately when compatible replacement rings are available and the hats remain within service limits.

Cooling and Slotted Friction Surface

Internally ventilated friction rings promote airflow through the rotor under rotation. The slotted contact surface is designed to work with suitable performance brake pads during repeated braking events. Proper ducting, pad selection and brake-fluid maintenance remain important for track use.

Brake Pads and Fluid

Retain the correct factory-caliper pad shape, using a compound suitable for iron rotors. For track use, choose a brake fluid with a suitable boiling-point specification and follow the vehicle and pad manufacturer’s bedding and service guidance.

Specifications

• Manufacturer: GiroDisc
• Manufacturer part number: A1-203
• Axle: Front
• Application: Porsche 991.2 Carrera / Carrera 4 / Carrera T, 718 Boxster S / Cayman S, and compatible 992.1 Carrera
• Rotor diameter: 350mm
• Original diameter for intended conversion: 330mm
• Construction: Two-piece floating
• Friction surface: Slotted cast iron
• Center hats: Aluminum
• Ventilation: Internally ventilated
• Quantity: Left and right pair
• Replacement ring part number: D1-203

Before Ordering

Confirm the original brake package, rotor dimensions, caliper configuration and pad shape. PCCB-equipped and previously modified vehicles may require different components. Contact Demon Speed Motorsports for help confirming fitment. Sold as a left and right rotor pair.