Our AP Racing by Essex Radi-CAL Competition Brake Kits have been a huge boon to 991 GT3 and 981 GT4 owners. Our system eliminates over 30 unsprung lbs. vs. the OEM iron brakes, simplifies pad changes tremendously, and preserves the OEM brake equipment for resale value. Most of our customers are also setting new personal best lap times after they install our equipment due to the confidence our brake system inspires. Please check out this monster thread on Rennlist for the development history of our similar kit for the 991 GT3, which contains lots of owner reviews and feedback.
"Radi-CAL" is a blanket term used to describe AP Racing's patented asymmetrical brake caliper design. Radi-Cal technology is grounded in Computer Aided Design (CAD) and Finite Element Analysis (FEA), and allows for organic, alien-looking designs that are a radical departure from conventional caliper designs of the past. Radi-CAL's are widely considered the pinnacle of current brake caliper technology. Since their inception in 2007, these revolutionary calipers have amassed a lengthy string of race victories at all levels of professional motorsport, while redefining brake performance expectations.
Complete Front AP Racing by Essex Radi-CAL Competition Brake Kit for the 981 and 718 GT4
The key benefits of the Radi-CAL design:
Massive Stiffness Increase- A 30+ % increase in both static and dynamic stiffness vs. conventional calipers allows for far less deflection under load, which means superior pedal feel & modulation, more even pad wear, and longer caliper service life.
Considerable Mass Reduction- Removing all extraneous caliper mass lowers the caliper weight, despite the huge stiffness increases.
Optimized Airflow- Air moves around and through the caliper more efficiently, providing superior heat evacuation and cooling.
Efficient Packaging- The asymmetric caliper profile and internal fluid porting allows the caliper to fit into tighter spaces.
Advantages Over OEM Brake System:
Simple pad change with two bolts, no caliper removal required
Saves 15 unsprung lbs. vs. OEM iron brakes and weighs almost the same as the OEM PCCB system
AP Racing Radi-CAL calipers are the stiffest, lightest, and most technologically advanced calipers available at any price
CP9661 calipers use a 18mm thick, commonly available brake pad shape
Ventilated, domed back, stainless steel pistons keep heat out of the brake fluid and provide an ultra-firm pedal
Mitigation of pad knockback via anti-knockback springs behind the caliper pistons
Anodized caliper finish that is resistant to wear and deterioration at elevated temperatures
Stainless steel caliper hardware for a long caliper service life under frequent pad change conditions
High temperature, low drag seals that will hold up to track temps= less rebuilding and longer service life
No dust boots to burn up
Lifetime professional caliper rebuilding support by Essex (at a fee)- pull off your calipers, send them to us, we clean, inspect, and rebuild them
Available disc burnishing service ensures that your kit arrives ready to be installed and driven hard immediately
Championship winning, 84 vane, fully floating, AP Racing J Hook racing discs with 12 attachment points to hat
Brake pads are NOT included with our system. Racing brake pads are a highly personal choice. Many manufacturers include a set of inexpensive, low quality pads with their brake kits. Rather than artificially inflating the price of our system with a set of pads you probably don't want anyway, we've decided to remove the cost from our system and allow our customers to choose the pads that best suit their needs/wants. When purchasing our kit, you are able to choose one set of front pads at a substantial discount vs. the retail price. Please use the drop-down menu to select your pads.
Features:
Front 9661/394mm
Eliminates the need to remove the caliper for pad changes
Saves 15 unsprung lbs. vs. OEM iron brakes and weighs almost the same as the OEM PCCB system
AP Racing Radi-CAL with durable, ventilated stainless steel pistons (no ceramic piston caps to break) with anti-knockback springs
Allows for the preservation of pricey OEM brake components
Huge array of brake pad options from all major pad manufacturers
Clears OEM 20" wheels without a spacer
394x34mm, 84 vane AP Racing disc fits inside many popular 19" wheels
Every component designed to resist the heat of extended track sessions
Pistons sized properly to allow for seamless integration with OEM master cylinder and ABS system
Designed to work with OEM rear brakes or our Essex/AP Racing rear BBK
Fitment:
Porsche 981 Cayman GT4 2016
Porsche 718 Cayman GT4 2017-2020
Notes:
Despite our larger 394mm discs (vs. OEM 380mm), our system has a smaller overall footprint. That means our system fits behind the OEM wheels with plenty of spoke clearance, and also allows for certain 19" track wheels.
AP Racing 2-piece J Hook Discs; work with OEM calipers!
AP Racing has been part of the automotive industry for more than 50 years. It started back in 1920 by Edward Boughton, Willie Emmott, and Denis Brock. They planned to import parts from the US to help maintain ex-military vehicles that were adapted for civilian use after Worl War 1. They later expanded their business by supplying parts for the British Motor Company.
Throughout the years, AP Racing has provided quality parts and specialized in clutches and brakes systems. Today, AP Racing has become one of the most recognized brands and has been well received by a lot of tuners, racers, and enthusiasts all around the globe.
AP Racing has participated in Motorsport racing and has helped produced race winners. As early as the 1930s they have already supplied parts for race cars in the British GP and have continued its tradition. In fact, it is being used by some of the best racing legends such as Jim Clark in his Lotus.
Continuous Innovation
AP Racing has always pushed itself in improving its products to create the best performing product in the market. It has helped jumpstart the development of brakes and clutch technology. The industry has come a long way from the time when brakes were made out of iron to the carbon ceramic composites of today alongside clutches capable of handling over 1000 horsepower.
Purchase AP Racing Products at Vivid Racing
When it comes to performance brakes and clutches, there are only a few brands that professionals trust and AP Racing is among the top of the list. With products that range from street applications to race-oriented brake and clutch systems, AP has it all. Visit Vivid Racing and check out the list of AP Racing products that would fit your specific needs.
By purchasing this product and opening this box, purchasers expressly acknowledge, understand and agree that they take, select and purchase these brake systems, parts, and equipment from AP Racing R, its affiliates, distributors, and agents (collectively, “AP Racingâ€) “as is†and “with all faults.†The entire risk as to the quality and performance of these brake systems, parts or equipment is with the purchasers. Should the goods prove defective following their purchase, the purchasers assume the entire cost for all necessary servicing or repair or any resulting liability. AP Racing R makes no warranties whatsoever, expressed or implied, oral or written, to purchasers or any users of these products. AP Racing R expressly disclaims any implied warranty of merchantability or warranty of fitness for a particular purpose, including fitness of these systems, parts or equipment for racing.
By purchasing this product and opening this box, purchasers expressly acknowledge that AP Racing R does not make or cause to make any representation or promise to purchasers which relate to the brake systems parts or equipment that becomes part of the basis of the bargain between AP Racing R and purchasers. Purchasers expressly affirm that they are relying upon their own skill and judgment in selecting and purchasing these goods as suitable for purchasers' intended use.
Purchasers understand and agree that no officer, director, salesman, distributor, or agent of AP Racing R has any authority to make any statement contrary to the terms of this disclaimer and agreement. On the contrary, AP Racing R disavows any statement contrary to what is written above.
WARNING: Cancer and Reproductive Harm
