Essex Designed AP Racing Competition Big Brake Kits in Development for 2015 Mustang

VRYALT3R3D said:

Is there anything in the pipeline from Stoptech or AP racing yet? I deleted the GTPP from my order. Plan is to turn my GT into a track car so I figured I would have ended up replacing most of the components in the GTPP anyhow.

Click to expand...

Hello Gents,

My company, Essex Parts Services, is the exclusive North American importer and distributor for AP Racing's line of competition brake products (as well as Ferodo, CL Brakes, Spiegler, etc.). We have a number of brake products planned for the 2015 Mustang, including at least one track-focused big brake kit (and possibly multiple variants). We purchased a Mustang GT a few weeks back, and expect to have it in about a month. At that time we'll dig into the project.

We currently offer our Essex Designed AP Racing Competition Big Brake Kits for a number of other popular track platforms including Corvettes, M3's, BRZ, etc. The goal with our brake kits is to bring the latest racing technology to the average enthusiast. Our kits are loaded with features that aren't offered by the OEM or other aftermarket suppliers: Ventilated stainless steel caliper pistons with anti-knockback springs, ultra-lightweight calipers, fully floating 2-piece 72 vane endurance racing discs, common pad shapes so it's easy to find any compound you want, low iron disc replacement costs, etc. Our goal is to make our customers' cars go faster, run longer, and cost less to operate on the track.

While the OEM Brembo packages are nice, they are still very much street brakes. If you'd like to see more about how the components we use are different, please check out this blog post I did on Brembo Road Calipers vs. AP Racing competition calipers.

You can read customer reviews and impressions on our Essex Blog.


Here is a bit more about myself and our company:

Personal Background
I've been the High Performance Division Mgr. at Essex Parts Services for roughly six years. Prior to that, I was the sales mgr. at StopTech for approximately 5 years. I've been autoXing/tracking cars since 1999, and my stable over the years includes or has included: '98 Integra Type-R, '03 350Z, '03 Z06 Corvette, '92 Miata, '04 CTS-V, '05 Legacy GT Wagon 5MT, etc. I've also been participating in online automotive forums since roughly 1999. You can find my posts under the screen name jritt across a wide range of forums: honda-tech, my350Z, corvetteforum, ft86club, m3post, etc. You can read my bio here. Chances are, there is someone on this forum who I've helped with brakes at one point or another.

I've also authored several articles and videos about high performance brake systems. Hopefully you'll find them helpful:

How to choose the best street and track brake pads

How to bed-in brake pads and discs

Big brake kit benefits you may not have considered

Essex Parts Services Background
Essex Parts Services is located in Charlotte, NC and has been in business for roughly 30 years. We are the exclusive importer and distributor for a number of high-end, mainly European brands including: AP Racing competition brake products, CL Brakes pads, Ferodo brake pads, Scorpion Exhausts, Spiegler SS brake lines, etc. You can read more about us here. Historically our focus has been on professional racing. More recently however, we've been working on bringing the technology from our professional racing experience into the aftermarket, and making it available to the average enthusiast. Many of the exclusive products we sell have either been used in professional racing, or contain a number of features that in the past have only been available at the higher echelon of racing.

Competition Big Brake Kit Project Background
A few years ago we began developing a line of brake systems geared towards heavy track users. We call them our Essex Designed AP Racing Competition Big Brake Kits, and we currently have applications for a host of popular racing/track day/AutoX/time trial cars: e36/e46/e92 M3, STI, Evo, BRZ & FR-S, C5/C6/C7 Corvette, Focus ST, S2000, etc. These systems are designed with the sole mission of making you go faster, and use the latest racing technology to improve performance. They focus on ultra-low weight, extremely durable materials, and inexpensive and readily available spare parts (pads and discs). They are built around components by AP Racing, arguably the top performance brake manufacturer in the world.

You can see some threads I've either started or participated in on some of the other forums for markets we support. They should give you a pretty good idea of how these projects typically take shape, as well as the end results we produce. As I mentioned at the beginning of this thread, we purchased our own GT, and we're all in for this platform. We are going to produce some killer brake products for these cars. If you have any intentions of tracking your Mustang, you are going to really like our products.

Forum post on our Essex E92 M3 Competition Big Brake Kits

Forum post on our Essex FT86 Competition Big Brake Kits

Forum post on our Essex Corvette Competition Big Brake Kits


If any of you have any specific requests or products that you'd like to see, feel free to contact me via PM or email.

Below are some pics our customers have sent us of them enjoying our products. At this stage we've amassed all sorts of race wins, lap records, and championships.

JRitt, that is some awesome info(and pretty pictures!). Can you offer insights on lightweight brake rotors and at what point does reducing rotor weight reduce their ability to shed heat and perform under heavy use? Also would two-piece rotors offer enough weight reduction to be felt(steering in particular) for a non-professional driver enough to justify the cost over a one-piece rotor?

Grimace427 said:

JRitt, that is some awesome info(and pretty pictures!). Can you offer insights on lightweight brake rotors and at what point does reducing rotor weight reduce their ability to shed heat and perform under heavy use? Also would two-piece rotors offer enough weight reduction to be felt(steering in particular) for a non-professional driver enough to justify the cost over a one-piece rotor?

Click to expand...

The outward appearance of an iron brake disc typically appears fairly simple, but there's actually a lot going on behind the scenes. When we design a disc we look at things like disc diameter, total thermal mass, number of vanes, vane style, disc wall thickness, air gap, overall thickness, radial depth, slot pattern, hat attachment style, required wheel fitment, metallurgy, etc. All of those factors contribute to the overall design and a given disc's ability to absorb and shed heat, and resist cracking.

When assessing a disc size for a new application, we ask ourselves the following: How much does the car weigh? How much power does it have? How much power could it have if our customer slaps a supercharger on it? What speeds will it reach on the track? How much tire can you cram under the fenders? On what tracks will our customers be running? How long will the sessions be that they're running? How big are the wheels that this car runs (we obviously need to fit behind them)? How much weight can we shave off vs. the OEM equipment? How thick can the disc be while still fitting a good number of popular wheels? What type of face groove/slot pattern does it need given the usage environment?

The ultimate goal in a racing disc is to only have enough heat capacity to get the job done. Anything beyond that is dead weight to drag around. It's a constant tradeoff between weight and performance, and that tradeoff becomes more and more important as you reach the higher levels of racing. For example, in F1 or NASCAR, teams are willing to sacrifice longevity for ounces. For our enthusiast products however, we tend to lean a bit more towards 'overbuilding' the discs to provide a long service life. As an example, we'll add a little more wall thickness to increase the service life so our customers aren't constantly replacing them as a pro race team would.

One thing to always keep in mind is that two discs of the same overall size/envelope can be very different in terms of performance. I'll use the C6 Z06 as an example. They come with a 355x32mm front disc. A fast driver on slicks at Road America should have no problem decimating a set of those discs in short order. Our Competition BBK for the C6Z06 also has a 355x32mm disc, yet we have customers running that same car an entire season or more on one set of discs. The discs are so different in their design and performance, that it's not even remotely an apples-to-apples comparison.

To specifically answer your question, yes, at some point a disc would become to lightweight to be effective on a particular application. It would not be able to adequately store or more enough air to keep the disc temperature down. At elevated temps it would become prone to cracking and deformation, and it would also increase the heat in other associated brake components leading to a host of other issues.

Another important question to address is where is the mass of the disc located? Most factory discs are one-piece, and have a heavy iron hat. Most aftermarket 2-piece discs use a lightweight aluminum hat. The mass of the disc is in the ring portion, where it needs to be to absorb heat, but the weight savings is in the hat/bell portion.

The weight is one big benefit of a 2-piece disc, but there are lots of other benefits as well. Take a read through one of our kit pages here...scroll down to the part on discs. That will explain things well.

As for steering feel, some people will feel a difference through the steering wheel, others won't. If you read through the reviews on our blog, it's fairly common for people to mention feeling a difference immediately. Those comments are typically referring to a complete kit install, which in our case often sheds 20+ lbs. off the nose of the car. Also, many people install new lightweight wheels when they upgrade their brakes. In those cases you're talking about someone shaving 15 lbs. of unsprung weight from each corner. I'm confident most people would immediately feel a difference of that magnitude.

As for cost justification, that's another interesting topic. Most people look at the short-term cost, and don't really think about a brake upgrade as an investment. Check out the article I wrote on Big Brake Kit Benefits you may not have Considered. Many of the same points hold true for 2-piece discs. Lower weight, run cooler, last longer, make your pads last longer, make your fluid last longer, wheel bearings last longer, resale value, etc....it all spirals. I can proudly say that in over ten years of selling aftermarket brake kits and discs, I've never had a single customer say, "I wish I hadn't installed those on my track car."

As we move through the development process, I'll work on documenting more precise points about what our products offer over the stock Brembo's. I will say that if I were ordering a GT today for my personal use on the track, I would likely do as others have suggested in the previous posts and order mine with the PP package. I would do so with the full intent of selling the PP front brake kit to another owner who didn't plan to track their car, and using the proceeds of that sale to upgrade the front brakes to more track-oriented hardware.

Anyway, thanks for listening guys, and feel free to fire away with questions, etc. :cheers:

Hot damn, I appreciate you taking the time to share that insight! While I originally decided I wanted the track package to get the big Brembos and various other bits, I'm now considering starting with a base model and adding my own more-focused setup. I will keep you in mind when I make my decisions.

Wow really awesome info. Great to see what you have done with other cars and looking forward to your plans for the S550.

Great info! Let me just say it's great to see a company that takes the time to educate people on the forum and not just plug their products. :clap2:

Out of curiosity any reason you guys are now getting involved with the Mustang?

Ponywars said:

Great info! Let me just say it's great to see a company that takes the time to educate people on the forum and not just plug their products. :clap2:

Out of curiosity any reason you guys are now getting involved with the Mustang?

Click to expand...

Thanks gents. We're happy to be here. I always think it's important with a purchase of this magnitude (typically thousands of $), that our customers know exactly what they're getting and what they can expect our product to do. I wouldn't plunk my own money down without having many questions answered, and I don't expect anybody else to do so either. I enjoy interacting with our customers, and in many cases this is unfortunately the only opportunity I'll ever have to actually 'meet' them.

We're getting involved with the Mustang market because track brake systems are our niche, and more and more people seem to be taking their Mustang to road courses for HPDE's, time trials, and wheel-to-wheel racing. Recent Mustang models have tremendous on-track potential, at a palatable price point for many enthusiasts. As such, we view the platform as a a great home for our products. We think they'll increase safety/reliability, lower running costs, and improve the overall experience people will have when running their car hard. Keep in mind that everyone in our organization is a current or former racer/enthusiast. We're all quite picky about our own vehicles, so we approach our products from that perspective.

I love all these new companies getting involved in the new stang. Ready for more updates!

Essex, glad to see you guys here! Can't wait to see what you guys have to offer.

I had the same caliper on my Evo, great improvement over the OE 4 pot brembo. Zero pedal fade and I was able to brake later as well. Pedal was always there when I needed it, after a few turns I'd have to tap the Brembos to be ready.

Can't wait till the kit comes out!

xXANCHORMONXx said:

I had the same caliper on my Evo, great improvement over the OE 4 pot brembo. Zero pedal fade and I was able to brake later as well. Pedal was always there when I needed it, after a few turns I'd have to tap the Brembos to be ready.

Can't wait till the kit comes out!

Click to expand...

Thanks for the kind words. :cheers: Our Mustang GT was supposed to be built this week, so we should have some R&D updates soon. That said, I want to show you what we'll actually be putting on the car...AP Racing's new Pro5000R calipers! We unveiled these at the SEMA show last week. Below is our press release for them:

AP Racing is proud to introduce the Pro 5000R line of brake calipers. Drawing heavily on our championship-winning Radi-CAL™ design philosophy, these highly optimized, forged calipers offer considerably lower weight and improved cooling vs. conventional designs, while improving dynamic structural rigidity.


The first AP Racing Radi-CAL™ caliper was introduced in 2007, and immediately took the professional racing world by storm. AP Racing has now produced over 80 different Radi-CAL™ variants, winning races and championships in all major motorsport classes around the globe.


With the Pro 5000R range, AP Racing brings this previously unobtainable technology to the club racer and weekend enthusiast. Despite its unmatched feature set, pricing will be similar to the outgoing Pro 5000 range.

Click to expand...

Now the part everyone likes...


This one will most definitely go on the car...CP9660:




And we'll likely have a CP9665 option for endurance racing:

Those look great! I like the reliefs in the SS pistons as well.

I'm guessing with the 9665 we'd lose some rigidity since the bridges are gone?

Either way I'm excited to see what these can do!

xXANCHORMONXx said:

Those look great! I like the reliefs in the SS pistons as well.

Click to expand...

Yes, the pistons on these calipers are ventilated, domed-back, stainless steel. They are the same spec we are selling in our current six piston kits. Details below from our website:

There are people out there who will tell you that aluminum pistons are great for track calipers. They will tell you that the expansion rates of the pistons and caliper body need to be the same when heated. This argument is completely invalid and unproven. Those same people tend to get upset when you point out the fact that every serious race caliper, from every serious race caliper manufacturer on the planet uses either stainless or titanium pistons, period. There is a reason for this: they work better!
Stainless steel pistons are far superior to aluminum pistons in creating a thermal barrier. They are much better at keeping heat out of your brake fluid and preventing a soft pedal from fluid fade on the track. This has been proven over and over again at all levels of motorsport. While most aftermarket calipers use a pressed aluminum piston, the CP5060 uses an expensive machined stainless steel piston.


To add stiffness to the pistons, AP designed the back of the piston with a domed back. At first glance this seems like a trivial design element. It is not. When domed back pistons were introduced in professional racing, driver feedback was immediate and resoundingly positive. The domed back adds considerable stiffness that can be felt through the pedal, and they have now become the standard vs. which all designs are judged.
For even greater heat resistance, we've also added ventilation/castellation to the pistons. The air gaps around the piston edge allow for even more cooling air circulation around the pistons. All of these features slow and repel the influx of heat into the brake fluid, preventing brake fluid boiling and fade.

Click to expand...

I'm guessing with the 9665 we'd lose some rigidity since the bridges are gone?

Either way I'm excited to see what these can do!

Click to expand...

The CP9665 will be delivered standard with both bridge inserts (shown in the pic below) and the spring clips. Our customers will be able to run either depending on their needs. Even with the spring clip installed, this caliper is far stiffer than anything else available. Dynamic stiffness is one of the inherent hallmarks of the Radi-Cal asymmetric design philosophy.

Awesome, that's great that you still have an option!

Thanks for the info and the pics!

Excellent option. I was seriously considering ther on my last z06. If I didn't have the big Brembos I'd be considering these.