C8 Corvette Stingray, Base and Z51 AP Racing by Essex Radi-CAL Competition Brake Kit Front 9668/372mm
Complete front AP Racing by Essex Radi-CAL Competition Brake Kit for the C8 Corvette Base and Z51:
Features AP Racing CP9668 Radi-CAL calipers with pads that are 1 inch thick
Allows for far easier pad change
2-piece fully floating, 372x34mm, 84 vane AP Racing disc
Saves approximately 12 unsprung lbs. from nose vs. OEM Z51 brakes
Every component designed to resist the heat of extended track sessions
Pistons sized properly to allow for integration with OEM master cylinder and ABS system
Designed to work with OEM rear brakes or our Essex/AP Racing rear BBK
Fits: Front (2020 Chevrolet Corvette Z51)
One pair AP Racing CP9668 Radi-CAL Pro5000R six piston calipers
One pair 372x34mm AP Racing CP6084, 84 vane, 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 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.
Pad Tension Clips (frequently referred to as anti-rattle clips) are NOT included with our Competition Kits, but we do offer them as an option if you're concerned about NVH. One of the great benefits of the AP Racing calipers in our system is that they are designed to accommodate pads from a wide range of manufacturers. Each manufacturer builds their pads with specifications that are slightly different. As such, pads from different manufacturers, or even from different batches, won't always fit in the calipers in exactly the same manner. Some pads are a snug fit, while others may rattle around and produce noise. The Essex Designed Pad Tension Kit is designed to dramatically reduce pad movement inside the caliper, along with just about all resulting noise. Click here to add the pad tension kits for the CP9668 calipers in this brake kit to your shopping cart. Please note that each caliper requires one Pad Tension Kit. If you need enough tension blocks for both of your calipers, you need to order two of these kits!
“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. For more details on the design concept and what these calipers have achieved in professional racing, please visit our blog and read The AP Racing Radi-CAL Story.
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.
CP9668 Pro5000R, The Everyman Radi-CAL
It has taken eight years, numerous generations of the design concept, and advancements in manufacturing techniques, but the Radi-CAL has finally evolved into a viable solution for racers and enthusiasts of all levels and budgets. While many products are supposedly born in racing, there can be no doubt about the Pro5000R pedigree. These calipers are direct descendants of the current crop of F1 and Sprint Cup calipers. They don't look ordinary, because they're not ordinary. They're the epitome of pure racing design: elegant, sparse, and brutally effective. And while they embody and employ the Radi-CAL design philosophy of the past, they also add some outstanding new features that enhance their practicality, convenience, and appeal. Quite simply, they are the lightest, stiffest, and most technologically advanced brake calipers that have ever been within the average enthusiast's grasp.
These intricate calipers have traditionally been machined from proprietary aluminum alloy billets. As one can imagine, machining away all of that material to achieve the final form is both time-consuming and costly. As a result, the price of these calipers has historically been prohibitive for the average club racer, time-trialer, or HPDE participant. Fortunately, the Pro5000R calipers use a new drop-forging technique that has dramatically lowered the manufacturing cost and the resulting price of entry, bringing this incredible technology to the masses.
Radi-CAL = Massive Dynamic Stiffness Increase
Over the years, many different strategies have been employed to shrink the brake caliper footprint while maintaining adequate stiffness: More robust caliper bridge designs, two-piece calipers with steel through-bolts, exotic materials (i.e. Beryllium, MMC), forging rather than casting, monobloc design, etc. All of these innovations pushed calipers towards becoming lighter, smaller, and stiffer. However, until the advent of the Radi-CAL, the same basic rectangular, boxy shape remained the accepted standard.
Is a rectangular box really the most appropriate and efficient shape for a brake caliper? AP Racing has now proven that it is not. As a brake caliper clamps brake pads against a spinning disc, a tremendous tangential friction force occurs between the pads and the spinning disc. In other words, the caliper is pulled strongly in the direction of the spinning disc, as represented by the downward pointing arrow on the right side in Figure 1 below. The caliper resists that force via the spindle hard mounting points, depicted by the upward arrow on the left. The dynamic load placed on the caliper twists or pulls the caliper into a parallelogram shape.
The product you’re after is currently not ready to ship, but please don’t panic! We can likely put it in your hands very soon. For brake kits or disc kits, we typically have the components on-hand to build one for you, and most ship within 2 business days of the order date.