AP Racing Radi-CAL Competition Rear Kit 365mm - Porsche 997.1 GT3

The AP Racing by Essex Radi-CAL Competition Brake Kit is a rear brake upgrade for the 2007-2008 Porsche 997.1 GT3 and GT3 RS. It pairs AP Racing CP9449 Radi-CAL Pro5000R racing calipers with 365 x 30mm, 72-vane AP Racing J Hook discs on fully floating aluminum hats, built for track days and competition driving.

Why upgrade

The kit removes about 9 lb of unsprung weight from the rear of the car compared with the OEM 997.2 GT3 iron brakes despite larger discs. The caliper takes a 16.75mm thick pad for long life and heat tolerance. The OEM parking brake keeps working. The caliper takes pads from all major pad manufacturers. Every component is designed to resist the heat of extended track sessions. Pistons are sized to work seamlessly with the OEM master cylinder and ABS.

Caliper and disc construction

On the Porsche 997.1 GT3, the CP9449 caliper mounts radially on a dedicated bracket at 152mm centers with a 44mm offset, with an M10x1.0 inlet thread. Anti-knockback springs behind the caliper pistons limit pad knockback. The anodized caliper finish resists wear and deterioration at high temperatures. Stainless steel caliper hardware gives a long service life even with frequent pad changes. There are no dust boots to burn up at track temperatures. Pads change with one bolt, with no caliper removal. The championship-winning 72-vane AP Racing J Hook discs are fully floating. The discs use anti-knockback, anti-rattle attachment hardware.

Features

• AP Racing CP9449 0-piston calipers
• 365 x 30mm, 72-vane J Hook discs on floating hats
• About 9 lb less unsprung weight
• 16.75mm thick brake pads
• Pistons sized for the OEM master cylinder and ABS

What's Included

• One pair AP Racing CP9449 Radi-CAL Pro5000R racing calipers
• 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

This rear kit fits the vehicles in the table below, which we confirmed against two sources using US model years. Call us about the Porsche 911 GT3, Porsche 911 GT3 RS and Porsche 911 GT3 RS 4.0 before ordering; we have not confirmed fitment for them yet. Check your wheel with the Essex wheel fitment template before ordering.

Fitment