AP Racing Radi-CAL ENP Competition Rear Kit - Subaru WRX/STI 2008-2021

This AP Racing by Essex Radi-CAL Competition Brake Kit in ENP finish is a complete rear big brake system for the 2008-2021 Subaru WRX and WRX STI. It installs AP Racing CP9451 Radi-CAL Pro5000R four-piston calipers and 340 x 28mm heavy-duty J Hook discs at the rear axle while keeping the factory parking brake working, so the car stays fully usable on the street after a weekend at the track or on a rally-cross course.

Why a rear kit

A front big brake kit fixes fade at the nose, but on a hard-driven WRX or STI the rear brakes are next to overheat. This kit is designed to match the AP Racing by Essex front Competition kits for these cars (CP9660 and CP9668 calipers with 355mm or 372mm discs), so front and rear share the same heat capacity. Because the factory parking brake is retained, the car stays legal and practical for daily use.

ENP finish and construction

Electroless nickel plating gives the calipers a jewel-like, liquid metal look, and the finish is very durable; a quick wipe brings it back to its original luster. Stainless pistons keep heat out of the fluid for a firm pedal, anti-knockback springs hold the pads in place, and high-temperature low-drag seals extend rebuild intervals. There are no dust boots to burn, and pads change with one bolt. The 48-vane discs ride on 6061 hard anodized aluminum hats with anti-rattle floating hardware.

Features

• AP Racing CP9451 Radi-CAL Pro5000R four-piston rear calipers in ENP finish
• 340 x 28mm, 48-vane heavy-duty J Hook discs on floating hats
• Retains the OEM parking brake
• Matches the AP Racing by Essex front Competition kits
• Spiegler stainless brake lines
• Brake pads can be added as an option at checkout

What's Included

• One pair AP Racing CP9451 Radi-CAL Pro5000R racing calipers in ENP (Electroless Nickel Plated) finish
• One pair 340x28mm AP Racing CP6565 heavy duty J Hook racing discs, with fully floating 6061 hard anodized aluminum hats and attachment hardware
• One pair caliper mounting brackets and hardware
• One pair Spiegler Stainless Steel Brake Lines with abrasion resistant coating
• Detailed installation instructions

Brake pads are not included.

Specifications

Video

Fitment notes

Fits the 2008-2014 Impreza WRX and WRX STI and the 2015-2021 WRX and WRX STI listed below. It does not fit the 2022 and newer VB WRX. Wheels must clear the 340mm rear disc; check aftermarket wheels with the wheel fitment template before ordering.

Fitment