The Pro-System GT86 rear package uses Alcon two-piston calipers with 34.9mm pistons. For a car whose braking system is being developed as a complete chassis package, the rear axle deserves the same attention as the front: pad support, operating temperature and consistent service specifications all affect how the car behaves through a braking zone.

Alcon / Pro-System Toyota GT86 Rear Brake Kit

BRK.200620 identifies this rear configuration. Its two-piston layout and 34.9mm piston diameter distinguish the package and provide the starting point for matching it to the rest of the car’s brakes. Keep that kit reference with the vehicle’s brake specification when ordering replacement components.

Features

• Toyota GT86 rear-axle application
• Alcon two-piston caliper configuration
• 34.9mm piston diameter
• Dedicated vendor rear-kit part number: BRK.200620
• Pro-System approach to a serviceable caliper, rotor and mounting assembly

Rear Calipers and Brake-System Balance

The caliper converts line pressure into pad clamping force. Piston area, pad friction and effective rotor radius all contribute to the braking torque at the axle, which is why a rear kit must be considered alongside the front system. The specified two-piston calipers use 34.9mm pistons. Retain the exact kit configuration when selecting replacement pads or caliper components rather than matching by external appearance.

Floating Two-Piece Rotors

Pro-System’s two-piece floating rotor design separates the iron friction ring from the aluminum mounting hat. Under repeated hard braking, the ring heats and expands much faster than the hub area. The floating attachment accommodates that growth instead of forcing the friction ring and hat to behave as a single rigid casting. It also provides a serviceable assembly: a worn ring can be replaced while a sound hat is retained.

Ventilation and Friction Surface

Braking converts the car’s kinetic energy into heat. The rotor must absorb that energy during the stop and release it between braking zones. Pro-System’s ventilated, slotted iron rotors combine internal cooling passages with a machined friction face. The vanes move air through the disc, while the slots help keep the pad contact surface clear. Rotor diameter, thickness, pad selection and cooling airflow all contribute to the system’s operating temperature.

Pro-System Rotor Preparation

Pro-System machines its iron rotors in Mooresville, North Carolina, using a specially formulated grey cast iron chosen for thermal stability and friction performance. Dyno bedding prepares the rotor friction surfaces under controlled conditions before installation. This preparation is part of the Pro-System approach to building a brake package, alongside precision-machined hats, dedicated brackets and floating rotor hardware. Pad inclusion and compound remain specific to the ordered kit.

Hats, Brackets and Serviceability

The rotor hat connects the friction ring to the hub; the caliper bracket locates the caliper relative to that ring. Their dimensions are application-specific, even when two kits use the same caliper family or rotor diameter. Keeping the correct combination matters for alignment, pad contact and clearance. Order replacement rings, hats, brackets and mounting hardware against the complete kit part number. Rotor bobbin components are supplied as complete hardware kits.

Friction Material and Track Preparation

The rear pad compound should suit both the intended temperature range and the front brake setup. Cold response, high-temperature friction and wear behavior all matter to the way the car brakes. A pad that physically fits is not automatically the right friction choice. Discuss the complete front-and-rear specification when selecting compounds for a track-focused GT86.

Fitment and Installation

Confirm the exact GT86 vehicle specification, wheel clearance and parking-brake requirements before ordering. Use BRK.200620 to identify this rear package; the newer GR86 rear kit is a separate reference and should not be assumed to share the same service components.

Replacement Parts

For replacement rotor rings, pads, calipers or mounting hardware, contact Alconkits with kit BRK.200620 and the axle being serviced. We will match the replacement to your exact configuration.

Gallery images show representative Pro-System component families. Application-specific components may differ.