KSport ProComp Rear Big Brake Kit

2008–2015 Scion xB (xB2)

BKSC040-862SO

Overview:

The KSport ProComp 16" 8-Piston Rear Big Brake Kit is engineered specifically for the 2008 to 2015 Scion xB (xB2) model, delivering exceptional stopping power and enhanced braking performance. Designed for enthusiasts seeking to upgrade their vehicle's rear braking system, this kit integrates advanced brake technology to reduce fade and maintain consistent pad contact under demanding conditions. Whether for spirited street driving or occasional track use, this big brake kit offers a significant improvement over the factory setup, ensuring greater control and confidence behind the wheel.

With a focus on durability and performance, the ProComp kit is an ideal solution for drivers looking to enhance their Scion xB’s braking capability without compromising reliability or ease of installation.

Key Features:

This comprehensive rear big brake kit combines cutting-edge materials and design to maximize braking efficiency and longevity. Key features include:

• 8-piston aluminum calipers for superior clamping force and improved pad wear
• D.O.T. compliant stainless steel brake lines that resist expansion under pressure for consistent pedal feel
• Large 405mm (16") ventilated carbon steel discs that improve heat dissipation and reduce brake fade
• Machined aluminum hats and carbon steel brackets engineered for strength and lightweight performance
• High-quality KSport SC5 street brake pads included, with optional RC1 race pads available for enhanced track performance
• Opposed piston caliper design that increases rigidity and evenly distributes braking force
• Two-piece floating disc assembly reduces unsprung and rotating weight for improved handling
• Aircraft-grade billet aluminum construction for lightweight durability

Construction & Design:

The ProComp rear big brake kit features calipers machined from aircraft-quality billet aluminum, weighing just over 5 pounds each. This lightweight construction reduces unsprung mass, contributing to better suspension response and overall vehicle dynamics. The calipers incorporate machined protection grooves for the bridge tubes, enhancing durability and resistance to wear.

Aluminum pistons paired with high-temperature seals ensure reliable operation under extreme heat, while stainless steel brake pad wear plates extend component life. The kit’s two-piece floating rotors are designed to efficiently dissipate heat and reduce thermal distortion, maintaining consistent braking performance during aggressive driving.

Installation & Fitment:

The KSport ProComp rear big brake kit is designed for straightforward installation with minimal tools required in most cases. It fits the 2008–2015 Scion xB (xB2) and requires 19" or larger wheels to accommodate the 16" rotors. Note that the OEM handbrake function will not operate with this kit installed, so it is recommended for users who do not rely on the factory parking brake system or who plan to upgrade to an alternative solution.

What's Included:

• Two 8-piston billet aluminum rear calipers
• Two 405mm (16") ventilated floating rotors
• Stainless steel braided brake lines
• Machined aluminum hats
• Carbon steel mounting brackets
• KSport SC5 street brake pads
• All necessary hardware for installation

Ideal For:

This big brake kit is ideal for Scion xB owners who demand enhanced braking performance for spirited driving, track days, or improved safety during daily use. It suits enthusiasts upgrading from stock brakes who want a reliable, high-quality system that reduces fade and improves pedal feel without excessive weight gain. The kit is also well-suited for those who prioritize durability and consistent braking under high-stress conditions.