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      07-20-2015, 12:40 PM   #23
e92zero
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I am very interested in this also but waiting for the whole front and rear package. So we are going to get the 352 disk only and not the 372 disk in the OP?
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      07-20-2015, 02:52 PM   #24
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any pics on m3s yet!!! come on whet our appetites!!
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      07-23-2015, 07:40 AM   #25
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Quote:
Originally Posted by e92zero View Post
I am very interested in this also but waiting for the whole front and rear package. So we are going to get the 352 disk only and not the 372 disk in the OP?
The rear package will likely remain the same as the current rear package, which can be seen here on our site.

Our front disc will be a 372x34mm, 84 vane...super heavy duty.

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any pics on m3s yet!!! come on whet our appetites!!
Not yet, sorry!
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      07-23-2015, 01:33 PM   #26
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Quote:
Originally Posted by jritt@essex View Post
The rear package will likely remain the same as the current rear package, which can be seen here on our site.
That's a bit disappointing. As good as the current package is, it doesn't really match the new design.

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Originally Posted by jritt@essex View Post
Our front disc will be a 372x34mm, 84 vane...super heavy duty.
This is nice.
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      07-27-2015, 05:34 AM   #27
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No release date yet?
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      08-03-2015, 08:14 AM   #28
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Originally Posted by E92cannon View Post
No release date yet?
No sir. As soon as we have a relatively firm timeline we will be sure to let everyone know. Thanks for your patience.
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      08-03-2015, 12:09 PM   #29
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Someone asked me about the weight of the new Pro5000R Radi-CAL kits...

The CP9660 caliper weighs just a little less than the CP5060 in our current kit. The CP9668 weighs about a half pound more, and the pads are heavier (25mm thick vs. 18mm thick). The 372x34mm disc weighs 3 lbs. more than the 355x32mm in our current kit.

Our current kit weighs 10.5 lbs. per side less than the OEM E92...21 lbs. off the nose total. So it will break down roughly like this:

CP9660/372mm= 7.5 lbs. less per corner vs. OEM
CP9668/372mm= 6.5 lbs. less per corner vs. OEM

So depending on configuration, you'd be knocking approximately 13-15 unsprung lbs. off the nose of the car.
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      08-04-2015, 07:16 AM   #30
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Hi Guys,
The new Pro5000R CP9660's got their first win over the weekend! One of our Corvette customers captured the NASA ST2 title at the NASA Nationals during a 25 lap race at Laguna Seca. Below is what he posted on the Corvette forum. His setup was the CP9660 on our 355x32mm discs.
I don't know if I'm happier about the win, or about the fact that the pads and discs have hardly any wear after an entire weekend of hard racing on a tough braking track! I should have some more pics and video soon.

Quote:
Thank you Jeff and the Essex team for my new Radi-Cal front brake kit! I was anxiously awaiting these to come out so I could retire my 10 year old Stoptechs. They arrived just a few days before my NASA national championship race. With most items I would be hesitant to make a big change right before a championship race, but I was confident with the AP brakes since I already had excellent success with the rear kit so I installed them, and I'm glad I did. BTW, the kit is very professionally done and packaged. It only took me one hour to remove my old stoptechs and install the new AP kit. The brackets fit perfectly with no grinding or shimming necessary. The calipers are a work of art.

This year's nationals were at Laguna Seca and once I put a session on them, I could definitely feel a difference in performance. The pedal position really jumped out as always being at the top and firm. Pedal modulation was easy and the brakes never changed over 30-40 minutes of hard racing. Zero fade and consistent braking at Laguna Seca which is notoriously brutal on brakes. It became obvious this brake setup was in another league from what I had been running. The rotors were capable of removing the heat and show no signs of heat checking after 3 days of racing. I was able to out-brake my competition and even the class above mine which was a huge advantage. After the race weekend both of my colleagues sharing the podium with me were asking about my brakes. They were that good.

After 3 days of hard racing is how they look. Good as new! I went with the narrow version. The wide version wouldn't fit some of my wheels but they would be amazing for longer races.




This situation is very reminiscent of the first time the Radi-CAL's were ever run in NASCAR Sprint Cup...they also took the win on the first time out. From our blog:

The first on-car application of the AP Racing Radi-CAL occurred during a confidential NASCAR test on August 6th, 2007 at Road Atlanta. Tony Stewart had won two out of the past three Nextel Cup races and was preparing for a race on August 12th at Watkins Glen International. Although Tony's team, Joe Gibbs Racing, was pushing towards the end of an extremely successful season on AP's latest conventional caliper system, AP encouraged the immediate implementation of the new CP5845 Radi-CAL based on the astounding results they had achieved during dyno testing (a 33% reduction in deflection vs. the leading caliper at the time). The Gibbs team liked the idea of a potentially significant technical advantage for the Glen, a track that is notoriously brutal on brakes, so they installed them on the car for testing.

Stewart drove the new Radi-CAL system back-to-back with the conventional AP short track setup, and the results were both instantaneous and impressive. Stewart and the team noted a marked improvement over the existing setup on all parameters: improved pedal modulation and required effort, a noted reduction in braking distance, and a substantial temperature reduction. In an unprecedented move at the elite level of the sport, the team decided after only one day of testing to run the new calipers in a race that was less than a week away!

The results at the Glen were just as dramatic and remarkable as what occurred during testing. Tony Stewart was leading the race at Lap 45, but spun going into Turn One. He then had to fight his way back through the pack, ultimately passing Jeff Gordon under braking in that same turn with only two laps remaining. Stewart went on to claim the win, and in doing so set the stage for the Radi-CAL's future dominance in motorsports. After the race, one of the larger teams complained to NASCAR officials that Stewart's Radi-CAL brakes offered him an unfair advantage. As a result of the ensuing investigation, it was decided that even though the CP5845 caliper was technically compliant with the rules, they couldn't be run again in a race until they were available to all of the teams. The calipers were immediately put into full production and adopted by most of the major teams. AP Racing Radi-CAL's have since been a fixture on most of the front-running cars in the NASCAR Cup series, and many other professional racing series as well.
- See more at: http://www.essexpartsblog.com/news/r....WLBQEqMN.dpuf

Last edited by jritt@essex; 08-04-2015 at 07:21 AM..
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      08-04-2015, 06:59 PM   #31
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Interesting that the new kits come with 372 mm rotors that weigh 3 pounds more than the 355s in the current kit. I just ordered the current kit with the 355 rotors and glad I did. I don't think I will be able to take advantage of the additional benefits of the 372 rotors or the new calipers, and would rather have the additional weight savings and cost savings from the 355s and CP 5060 calipers. Of course I'm just a novice on the track, but for me I don't think the Pro 5000R kit is the better choice compared with the CP 5060 kit.
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      08-06-2015, 08:58 AM   #32
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Quote:
Originally Posted by ajshanny View Post
Interesting that the new kits come with 372 mm rotors that weigh 3 pounds more than the 355s in the current kit. I just ordered the current kit with the 355 rotors and glad I did. I don't think I will be able to take advantage of the additional benefits of the 372 rotors or the new calipers, and would rather have the additional weight savings and cost savings from the 355s and CP 5060 calipers. Of course I'm just a novice on the track, but for me I don't think the Pro 5000R kit is the better choice compared with the CP 5060 kit.
When we launch these new kits we are going to continue to offer our current kit. It's a matter of taste and needs. For most people the 355x32mm disc will be ample from a needs perspective. As I've mentioned many times in the thread about our current kit, we've had many extremely fast and powerful cars have great success with the 355mm disc. To my knowledge we have never had anyone with an M3 or 1M fade our 355mm disc. It most definitely eclipses the performance of all other 355's, and even larger discs from other manufacturers. They are incredibly stout discs, and the Yost M3 ran a full 25 Hour race weekend on one set.

All of that said, from day 1 we've been bombarded with requests for a larger disc option. If there's one thing we do, it is listen to our customers. Now we'll have choices to suit various needs and wants.
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      08-14-2015, 08:19 AM   #33
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These kits are now in production for the E92 M3!

Our tentative shipping date will be at some point in October.

You will have the choice of either the CP9660 or CP9668 caliper. They will both use the same bracket and will both fit on the same disc. Hypothetically, you could have both calipers, depending on your needs (i.e. if you ran both Sprint and Endurance races and wanted to optimize your setup for each venue). The two different calipers will be interchangeable.

As for discs, below are some comparative pics of the 355x32mm, 72 vane disc in our current kit, and the 372x34, 84 vane disc in the new kits. I also have some final weight numbers from the production parts. The 355mm iron disc weighs 15.35 lbs. without a hat/hardware. The 372mm weighs 19.1 lbs.




Now, here's the best news...the 372mm discs will fit inside 18" wheels! While some manufacturers have gone a little bonkers disc diameters, we've purposefully constrained the disc diameter on these to completely fill out an 18" wheel. We added thickness and vanes to gain thermal capacity, rather than stretching them to a silly diameter.

Below are some pics of our CP9668 fitment template being checked inside an aftermarket 18" wheel from an e92 M3. Again, this template is for the wider CP9668 caliper that takes the 25mm thick pad. Even with the wider caliper there is plenty of clearance on both the wheel spoke and barrel.

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      08-15-2015, 07:43 PM   #34
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can the pro5000r caliper be used with the 355mm disk for the most weight savings?
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      08-16-2015, 11:20 PM   #35
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I've been looking forward to this but I'm a bit disappointed really. To me it doesn't make a lot of sense to get the new 372mm Radi-Cal front kit and match it to the proportionally much smaller 340mm rear kit with the old style caliper.
Looks like I'll have to wait for Essex to come out with a more evenly matched Radi-Cal based rear kit before I jump in.
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      08-17-2015, 07:28 AM   #36
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^ +1

Was just about to post this up. I was considering to get the CP5555 rear (378x36mm) and the CP6602 rear (352x26mm) but was contemplating with the older Essex kit and then this popped out which looks spectacularly bada$$

But I did notice that the rear 5000R 4piston (rear) caliper by AP Racing doesn't accommodate a larger brake disc, which is a problem.

I do have a question though. Is there a specific ratio that would cause imbalance towards the car's handling characteristics if you have a larger diameter front disc VS smaller diameter rear disc? That would be interesting to find out.
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      08-17-2015, 12:00 PM   #37
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Quote:
Originally Posted by Striker73 View Post
^ +1

Was just about to post this up. I was considering to get the CP5555 rear (378x36mm) and the CP6602 rear (352x26mm) but was contemplating with the older Essex kit and then this popped out which looks spectacularly bada$$

But I did notice that the rear 5000R 4piston (rear) caliper by AP Racing doesn't accommodate a larger brake disc, which is a problem.

I do have a question though. Is there a specific ratio that would cause imbalance towards the car's handling characteristics if you have a larger diameter front disc VS smaller diameter rear disc? That would be interesting to find out.
We might release a Pro5000R rear kit somewhere down the road. As mentioned above though, AP's current CP9441 Pro5000R isn't appropriate for the rear of the M3.

You can however bolt the new front 372mm Pro5000R BBK onto a car with either the OEM rear brakes, or our current CP5040/340x28 BBK.

Brake torque output is impacted by piston size, disc diameter, and pad mu (we hold pad mu as a constant). Our brake kits are designed to very closely mimic the OEM torque output on the axle on which they are installed. We do so by carefully sizing the discs and caliper pistons.

Disc diameter/size is primarily about heat. You choose a disc for a particular application based on its thermal mass. You look at the platform and ask yourself, "Will this disc have enough mass and cooling capacity to handle what a modified M3 on slicks, at a fast track, with a good driver at the wheel can throw at it?" Once you choose the disc that will manage the heat appropriately, then you choose your piston sizing. We choose piston sizes that in conjunction with the chosen disc diameter will provide a brake torque output that is very close to stock. By doing so, you keep the integration seamless...no ABS issues, no overamplifcation of brake torque on a given axle, no extreme pedal effort required, etc.

As such, installing our front kit on your car will only have a negligible impact on brake bias, and you could even run our rear BBK with the OEM front brakes without any issues. In other words, the disc diameter front relative to the rear isn't an issue as long as the pistons mated up to those discs are sized properly. That's the key point.

We now have a whole bunch of our rear 340x28mm discs on the rear of e92 M3's. We have not had a single incident of a customer fading or having any issues with our rear setup (including being pushed to the limit in a 25 hour race). As such, there is no need to go to a larger rear disc (other than aesthetics). Adding a larger rear disc simply adds unnecessary weight to drag around. Also keep in mind that our current rear disc is large enough to keep the factory rear parking brake, which is important to some people.

Quote:
I've been looking forward to this but I'm a bit disappointed really. To me it doesn't make a lot of sense to get the new 372mm Radi-Cal front kit and match it to the proportionally much smaller 340mm rear kit with the old style caliper.
Looks like I'll have to wait for Essex to come out with a more evenly matched Radi-Cal based rear kit before I jump in.
It actually makes perfect sense. If there's anywhere the e92 M3 needs a larger disc and heat capacity, it's on the front. That is where the bulk of the brake demand is on these cars. From a functionality standpoint, there is zero need to go to a larger rear setup. It's just unnecessary added unsprung weight (see my points above). If you can win all-day endurance races with the current rear setup while still having plenty of disc life left, why would you want anything bigger?

Also as mentioned above, if you're dead set on waiting for a different rear, there's no reason you can't just install the front kit and see if you even need or want the rear after beating on the front for a while. Again, our front kits bolt onto an otherwise stock car and integrate seamlessly with the OEM rear brakes. We have tons of customers who do exactly that, and the kits work spectacularly as a front-only solution. If you install the fronts and find out that you're not having any rear brake issues at all, that your rear pad and disc wear rates are acceptable, etc...you just saved enough $ to pay for a few sets of tires.

Quote:
can the pro5000r caliper be used with the 355mm disk for the most weight savings?
No sir. For the foreseeable future we will only be offering the 355x32mm discs with our existing BBK. We're trying to keep the number of kits we have for each platform manageable. We'd like to have 17 different kit options for every platform, but we just don't have the resources to do so. I will say that the more success we have on a given platform, the more likely we are to cater to every customer need and want. As an example, we've had tremendous success in the Corvette market over the past few years. As a result we now have seven front brake kit options and a couple of rear kit options. Our 'menu' for those cars looks like this:

Available front BBK's for C6 Corvette:
CP8350/325x32mm
CP5060/355x32mm
CP9660/355x32mm
CP9668/355x32mm
CP9660/372x34mm
CP9668/372x34mm
CP9040/362x32mm (Factory...painted calipers)


Available rear BBK's for C6 Corvette:
CP8350/325x32mm
CP5040/340x28mm

The point is, the more owners that support us in a given platform market, the harder we will try to cater to that market's every specific need. We're busting our humps flat out every day to keep up while working with limited resources, so it has to be that way. It is a good problem to have though, and we're trying to provide the solutions for which we are getting the most requests. In this case, the number one request among e92 M3 owners over the past year has been a larger front kit with the latest AP Racing technology...so that's what we're producing next! Hopefully if all goes well we'll keep the momentum going for this chassis and produce more killer products that people want.

Regardless, our new front 372mm kits are going to be totally bad@ss. The only other place you can find similar products and technology is on race cars worth many hundreds of thousands of dollars to millions of dollars. I think the fact that we're putting that in peoples' hands for around $4k is a pretty ridiculous deal.

Now I'm off to explain to some Dodge owners why we can't provide our kits with yellow calipers that have a viper logo.

Thanks for your patience gents. I can assure you that these kits will be worth the wait.
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      08-17-2015, 12:37 PM   #38
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Spoken like a true contender. This is exactly what they engineered their kits for; race spec and race spec only. Love the points noted. If aesthetics is your primary goal you can consider going elsewhere but if stopping power and weight are your concerns this is the kit.

AP curious if you've toyed with 8piston set ups; specifically for e9x chassis
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      08-19-2015, 07:03 AM   #39
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Quote:
Originally Posted by steven_s View Post
Spoken like a true contender. This is exactly what they engineered their kits for; race spec and race spec only. Love the points noted. If aesthetics is your primary goal you can consider going elsewhere but if stopping power and weight are your concerns this is the kit.

AP curious if you've toyed with 8piston set ups; specifically for e9x chassis
Thank you!

Our kits are definitely designed with function as the top priority. They are beautiful, but their unique aesthetic is a side effect of their functional design.

We have not considered using 8 piston calipers, as they are completely unnecessary on this application. As a general rule of thumb, if you can generate enough brake torque with a six piston and have enough pad volume, that's the better option vs. an eight piston for several reasons:
  • Having extra pistons over-complicates things...more parts to replace when you rebuild, more potential parts to fail, extra pistons weigh more, etc.
  • The more pistons you have, the longer the caliper gets to accommodate those pistons. As the caliper gets longer, it lengthens the 'box' formed by that caliper. That means the structure is going to be more rectangular, less square, and less stiff.
  • Related to both of the above...brake pads. You don't want a brake pad that is a mile long, as it will end up with tapered wear. Some implementations of eight piston calipers solve this by going with two pads per side on an eight piston...one pad for every two pistons, which is four pads per caliper. That makes things even more complicated when keeping spares, more expensive to buy pads, etc. Check out the front calipers of an Audi R8/Lambo Gallardo as an example...you need to buy four boxes of pads to change out the fronts, rather than two!
  • A long caliper covers up a larger portion of the disc, which doesn't do your cooling any favors. Heat-soaked brake pads sitting on half of the disc doesn't help with the radiation of heat from the disc iron.

An eight piston caliper is a great idea if you need more brake torque. Let's say you have a big truck, and the combination of pistons in your six piston caliper can't generate enough brake torque. Then an eight piston is a great option. Otherwise, the six is usually the simpler, more efficient, less expensive solution.
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      08-19-2015, 10:00 AM   #40
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Britt can you confirm if that front rotor will bolt up to my z4m kit that i current have, i use a 355 x 32 rotor but of course on the z4m specific Bell.

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      09-30-2015, 04:32 PM   #41
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Garage List
Thanks Jeff for answering all my questions about this kit. Cannot wait to have these installed!
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      10-01-2015, 10:50 AM   #42
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Hello again Gents. You're now about to witness the strength of track knowledge. Pre-orders for the most technologically advanced and capable brake kit ever developed for the e92 chassis are now officially open! Orders will be fulfilled in the order in which they are received. These kits will start shipping in 2-3 weeks.

I'm sorry that these kits aren't up on our current website, but we're in the midst of a complete site redesign. They'll be up on our new site in about a month. All the info you need can be found in either in this thread, or we're more than happy to answer any questions you might have on the phone (704)824-6030.

Front Option#1: CP9660/372mm- $4099
Part#13.01.10037
Wheel fitment template e92 M3 CP9660/372mm



Front Option#2: CP9668/372mm- $4499
Part#13.01.10038
Wheel fitment template e92 M3 CP9668/372mm





The only difference between the two kits above is the caliper. The CP9660 is narrower and uses an 18mm thick pad. The CP9668 is designed for endurance racing, and uses a 25mm thick pad. It also includes the spring clip bridge option for ultra-quick pad changes. For most people, the CP9660 is going to be more than adequate, and saves about 3/4 of a pound per caliper. It also offers better wheel spoke clearance. If you're endurance racing, then the CP9668 caliper option gives you a thicker pad that can be changed out more quickly during a pit stop if required.

The summary below pertains specifically to the CP9668 option. Just about everything holds true for the CP9660 as well. Again, the weight difference between the CP9660 and CP9668 calipers is a little less than a pound.


Summary of Benefits vs. OEM e92 M3 Front Brakes

Saves approximately 12-14 lbs. unsprung weight from nose vs. OEM brakes

AP Racing Radi-CAL calipers are the stiffest, lightest, and most technologically advanced calipers available at any price

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

Simple pad change with two bolts or quick-change spring clip, no caliper removal required

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 endurance racing discs with 12 attachment points to hat

Anti-knockback/anti-rattle disc attachment hardware

Replacement iron disc rings available at an extremely competitive replacement price $399

Disc metallurgy specifically designed to handle the temps typically seen on track offer a long service life

Highest quality, Spiegler stainless steel brake line with clear sheath that reduces compliance over OEM rubber design

What's In The Box?



• One pair AP Racing CP9668 Radi-CAL Pro5000R racing 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 50% discount. This offer is valid on any of the brands/compounds that we offer.

Radi-CAL
“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 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 dynamic force exerted on the calipers during a braking event is the key to the magic of the Radi-CAL design philosophy. Brake calipers of the past were designed to some extent in relative isolation from the forces that they were attempting to combat. They were designed to be the stiffest box possible while resting on a table, with much of the caliper mass residing at either end. The Radi-CAL is dramatically different because it was deliberately designed around the braking event forces that will be acting upon it. This is achieved by optimally distributing the body mass of the caliper on a diagonal, rather than at the two caliper ends. As such, the forces dynamically acting on the caliper are supported by the caliper mass, rather than what historically has been an empty box (see Figure 2 below). At the same time, this also allows for a significant reduction in overall mass, because all non-essential, non-load-bearing caliper body material is removed. So in the case of the Radi-CAL, it's not just about the material that is put into the caliper, it's about the material that is taken away!







Radi-CAL= Ultra-lightweight, Compact Design with High Airflow

As mentioned above, the Radi-CAL design philosophy is just as much about what isn't there, as it is about what is there. The Radi-CAL design relocates caliper mass, creating voids that would traditionally not be located where they are. As such, considerable mass is removed from the body, and the entire envelope of the caliper is optimized. The result is an extraordinarily lightweight and compact footprint. Whereas many competing six piston calipers weigh in the 9-12 lb. range, the CP9668 weighs an astounding 6.8 lbs.!

The Essex mantra when designing brake kits has always been, "Anything larger than necessary to get the job done is simply dead weight to drag around," and the Radi-CAL aligns perfectly with those values. One of the major problems with many of the brake packages currently on the market is wheel fitment. You’re offered gigantic discs and 12 piston calipers, with a pat on the back and a, “Good luck finding wheels to clear those things (insert sinister chuckle here).” The reality is that many casual racers want to use their OEM wheels on the track, or the smallest, lightest wheel they can find. Not only is saving unsprung weight critical, R compound tires are much more plentiful and cheaper for smaller wheels. If the components are designed properly with heavy use in mind, you don’t need to cram boat anchors under your wheels. If you’re worried about the loss of stiffness due to mass reduction, don’t. Some manufacturers use a heavier six piston caliper, but that's because the caliper wasn't designed or optimized for racing. In those cases, the same caliper may have been designed for use on much heavier road cars, and even trucks! AP Racing’s Pro5000R calipers are incredibly stiff, and designed from scratch with only the racetrack in mind.

Take a look at the caliper above or below. Anything else missing? Outer bleed screws and crossover tubes! The Pro5000R range has internal fluid porting and only two bleed screws located on the inner caliper half. That means that the chance of knocking a bleed screw or denting a crossover pipe during a wheel change virtually disappears. It also means that you now have half as many bleed screws to turn when changing your brake fluid. Eliminating the piping and bleed screws also allows the outer corners to be rounded, improving wheel spoke clearance.

Finally, take a look at the picture below. Compared to a traditional caliper, the pistons and brake fluid pathways have far more airflow between and around them, lowering the overall system operating temperature.



Two-piece, Drop-Forged Caliper Body


Radi-CAL's such as the one in Figure 2 above have traditionally been machined from a single, solid block of proprietary aluminum alloy (monobloc). With a monobloc design, the piston bores and piston seal grooves can only be machined with a right angle machine tool (the tool must be inserted up and into the caliper). As one can imagine, machining away all of that material with special tools and multiple setups to achieve the final form is both time-consuming and costly. As a result, the price of monobloc Radi-CAL's has historically been prohibitive for the average club racer, time-trialer, or HPDE participant. The Pro5000R has been made possible by a newly developed 2-piece drop-forging process, which allows a conventional machine tool to access the piston bores via a direct path. The result is a drastic reduction in both production time and cost, while still retaining an incredibly stiff form.




Hard Anodized Finish

The first obvious weakness when looking at a typical aftermarket caliper is the finish. Most aftermarket calipers come in a painted finish, whether they are red, black, or gold. That painted finish is designed to look pretty and prevent corrosion in harsh winter environment. Unfortunately, for all of the compliments painted calipers generate, there is an associated price if you drive the car in a track environment. That price is the chipping, flaking, fading, color shift, and general degradation of that finish in a fairly short period of time. Some OEM calipers can go from the as-delivered color to a nasty shade of brown in as little as one weekend. While this is typically worn as a badge of honor among our more hardcore customers, let’s face it…they still look terrible. More importantly however, all of those bits of paint end up in places they’re not supposed to, which we’ll get to in a minute.

Why does this happen? Heat. Paint and powder coat cannot adequately handle track temperatures. Powder coat also has some notorious issues with shrinkage. The powder coat layer expands and grows when the caliper is heated. When it cools, the powder coat doesn’t necessarily shrink in step with the caliper body itself. What’s left is a loose shell of finish hanging limply on the caliper body. That shell then cracks and falls to pieces.

Paint can also have similar issues depending on how it is applied. If you were to line up a few aftermarket calipers from the same manufacturer, you would likely see that the painted finish on each of those calipers is slightly different. Some have a thicker coat, some thinner, slightly different shades of red, etc. Painting is to some extent an art form, and must be performed in a tightly controlled environment. If it isn’t, you’re always going to see variation. A thick coat makes the part look soft around the edges, and is prone to cracking off in the same manner as the powder coat described above, leaving the underlying finish exposed. A part without enough paint will look uneven, and will not protect the underlying aluminum particularly well either. In addition to problems with cracking, flaking, and uneven application, paint and powder coat also experience extreme color shift when heated. Red becomes maroon or black, gold becomes brown, and black just gets uglier.

The calipers we are using in the Essex Radi-CAL Competition Kits are ultra-lightweight, stiff, and durable under all track conditions. The finish is a hard anodizing, which is the business under track conditions. When raw aluminum reacts with the oxygen in the air, a hard surface film develops on aluminum which prevents further degradation. The process is called oxidation, and you can think of it like rust. The anodizing process leverages this natural phenomenon, and takes it a step further to produce an extremely hard protective layer of aluminum oxide. It does so by running an electrical current through an acid bath, and dying it to the desired color. If you want to know more, Google it.

The result is a finish that is far more appropriate for racetrack use. Anodizing creates a uniform surface that is much more abrasion resistant than paint or powder coat. That means if you ding an anodized caliper with a box wrench when bleeding it, a big chunk of the finish isn’t going to chip off into your hand. While anodized calipers will still exhibit color shift, it will take a lot more heat to get them to change, and they won’t change as dramatically. More importantly though, you aren’t going to have bits of anodizing sticking to the sides of your pistons.




Brake Pads in A Commonly Available Shape

The basic pad shapes for the Pro5000R calipers were created by AP Racing many years ago, and are used by a wide range of racing calipers today. They're available in just about every popular racing compound on the market. That means you’ll never end up in a pinch without pads.
Below is a drawing of the basic pad shape:



Dimensions= 152.1 x 54 x 25 mm

Pad Retention Loop

The basic pad shape comes from some manufacturers with a small loop on the top edge (the portion above the red line in the drawing above). On certain calipers a pad retention pin is placed through that loop to hold the pads in place. That small loop is not used in the AP Racing Pro5000R Radi-CAL's however, and must be removed for the pads to fit properly. If the pads you're planning to run have that loop, you'll need to remove it from each pad before use (it can be sawed or ground off in a matter of seconds).

Pad Thickness, CP9660 caliper (18mm) vs. CP9668 caliper (25mm)

For many of the platforms we are servicing, we have both the CP9660 and CP9668 calipers available. The biggest difference between these two calipers is the thickness of the pads that they can accommodate. The CP9660 caliper uses an 18mm thick pad in the above shape, while the CP9668 caliper uses a 25mm thick pad. Which one is right for you? If you're running multi-hour endurance races, or want to reduce the frequency of pad changes, the CP9668 is likely your proper choice. If you're running standard 20-40 minute HPDE/Time Trial sessions, or sprint races, the 18mm thick pads will be more than ample. There are two primary trade-offs when going with the CP9668 caliper: It is about a pound heavier (including the difference in pad weight), and roughly 14mm wider than the CP9660. You will lose that 14mm on wheel spoke clearance vs. the CP9660 kit, so please make sure to check both fitment templates if you're debating caliper choice.

The available pad compounds that Essex sells for the CP9668 caliper can be found below. Please keep in mind that there are many other compounds available on the market from other manufacturers. The list below represents only what Essex sells. When purchasing our system, you have the option of buying one set of brake pads at 50% off of the retail price. Underneath the manufacturer list below, the pad compounds are listed from most aggressive to least aggressive.

CL Brakes

RC8
RC6
RC6E
RC5+

Ferodo Racing

DSUNO
DS1.11
DS3000
DS2500

Hawk Performance

DTC-70
DTC-60
HPS
Performance Ceramic

Note on using brake pads different from those listed above

Again, please keep in mind that the above is not an exhaustive list, and that there are many other pad compounds available in this shape from other manufacturers. Please note however, that the pad shape we use in our caliper is available in a variety of radial depths (heights), and that Essex recommends the 54mm radial depth version. Another common radial depth in this pad shape is 51mm. The 51mm depth pads will fit into our caliper, but you will be leaving an unswept 'ring' around the disc near the attachment points to the hat (the pad will not hang as low in the caliper). Leaving a portion of the disc face unswept can create a temperature differential across the face of the disc, and doing so could lead to premature disc cracking.

Pad Cross Reference
Since we do not sell most of the brands listed below, Essex cannot guarantee the fitment of these pads in the AP Racing CP9668 caliper, and they may need to be modified as shown above (loop removed). Based on our research however, we believe that these are the appropriate cross references for the basic shape. However, you should verify with either the manufacturer or your installer prior to purchasing any of them for use in the Pro5000R calipers.

Manufacturer Part Number 18mm 25mm Depth
Alcon PNF4489X532.4 X X 52
AP Racing CP3894D54 X X 54
Brembo B51 X X 54
Carbotech CTP7790A X ? 54
Circo MB1658-25 X X 54
CL CL5009 X X 54
Cobalt AP5 X X 51
EBC (DP2006, DP3006C, DP4006) X ? 54
Endless RCP086 (D52) X X 52
Ferodo FRP3003 X X 54
Hawk HB109 X X 54
Mintex 1852 X X 51
Pagid U1903 X X 54
PFC 7790.XX.18 X X 54
Porterfield AP7790 X X 54
Project Mu F1090 (D52.5) X X 54
Raybestos R2600 X X 54
Wilwood 8825 X X 51

Ventilated, Domed Back, Stainless Steel Pistons

There are people 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 steel or titanium pistons, period. There is a reason for this: they're 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 Pro5000R's use 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, there is ventilation on each piston. 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.



Anti-knockback Springs

Not only are the pistons stainless steel, they are also fitted with anti-knockback springs. Springs in pistons you ask? Yes, springs. If you’ve ever gone through a series of S turns and then had your pedal drop when going into the following brake zone, you have experienced knockback. To say it is disconcerting is an understatement. You’ll often see pro drivers ‘pre-tap’ their brakes lightly when approaching a brake zone. They are fighting knockback.

Knockback is a phenomenon that is common with fixed calipers. Knockback occurs when your car’s wheel, hub, and bearings deflect during cornering, allowing your brake disc to move out of sync with your caliper and brake pads. The amount of knockback varies by vehicle, and depends on the amount of deflection seen in the parts listed above. As the brake disc deflects, it actually pushes the pads away from each other, forcing the caliper pistons back into their bores. The piston seals don’t have enough tension in them to completely return the pistons to their original location. That means there is slack in the system that needs to be taken up. When you press the brake pedal, it will continue to drop until that slack is taken up.

Anti-knockback springs help alleviate this situation by putting some tension on the back side of the pistons. When the disc deflects and makes contact with the pistons, the springs push the pistons back into their proper location, reducing slack in the system. That means less pedal drop and far fewer pucker-factor moments when going into heavy brake zones.

There are no major downsides to lightweight AKB spring as long as the caliper is designed to accommodate them. More specifically, AKB springs do not create any increased drag or wear on the pads and discs as long as the shape and material of the piston seals takes them into account.

As you're driving the suspension is constantly compressing, the disc is moving around laterally, and the pads are being pushed slightly away from the disc. Think of the seals in the caliper as a spring or hinge attached to the side of the piston, rather than just a ring through which the piston slides. In an AP Racing competition caliper, the groove in which the seal resides isn't a square cut groove.It has angles. When the pistons slide in or out there is friction between the outer piston wall and the seal, and the seal distorts a bit as shown in the illustration below.

A caliper piston sliding out to the left would distort the seal in this manner (the slashes are the seals on either side of the piston):

/
---
---
\

As the piston slides back in to the right, the seal does this:
\
---
---
/

There is a certain amount of tension or friction that needs to be overcome before the piston actually starts moving through the seal ring. That tension/friction keeps the piston from dragging on the disc once the pistons are pushed back into the bores by the disc/suspension movement.

When AKB springs are added, a little more force is required to push the pistons back into their bores than would be required without them. After the spring is compressed, it unloads and pushes the piston back to 'neutral.'

With the proper seal and spring the goal is to keep the piston in the 'neutral' position, not pressed against the disc. The piston is still able to slide freely in either direction, but a bit of friction or tension needs to be overcome initially to get it moving in either direction. The seal offers that first bit of friction to limit movement, and then the spring provides additional resistance. The end result is that the properly designed AP Racing calipers won't drag or create additional or unnecessary wear.

High Temperature, Low Drag Seals Without Dust Boots

We are often asked by potential customers if the calipers in our kits require frequent maintenance and rebuilding because the pistons don't have dust boots. We are perpetually shocked by this question because it makes no intuitive sense. If you have a product that is specifically designed to handle the extraordinary high-heat conditions of track use, why would it require more maintenance when used under those conditions vs. brake components that were designed to cruise around on the streets at low speed and temperature?
Many people confuse piston seals with dust boots. All calipers have seals. They're the little rubbery rings inside the piston bores (see pic below). If a caliper didn't have a seal, your brake fluid would leak out around the pistons! OEM caliper seals aren’t designed to handle constant trips to several hundred degrees without becoming brittle and leaking. Our calipers use special high-temp seals designed for track use. They are the exact same high temperature seals used in NASCAR Sprint Cup, ALMS, DTM, etc. That means they are less likely to get brittle and wear out when used under high-heat track conditions, and they require far LESS frequent replacement and servicing.

Most aftermarket calipers are designed for year round road use, and as such come with a bellows style external dust boot like the ones shown below. The rubber boot stretches as the piston extends, and its objective is to keep contaminants out of the piston bore. It's a nice concept, but we've seen customers burn those up in a single 20 minute track session! Once that happens, you're simply driving around with some tattered, burnt rubber bits attached to your pistons. At that point they're providing zero benefits to you. If you're going to instantly destroy them when you go to the track, why worry about having them in the first place? We skip making that mess for you by eliminating them from our design.

Simple Pad Change with Two Bolts, or Quick-Change Spring Clip

After the countless times you’ve changed your brake pads, you’re probably never too excited when it comes time to do so. Changing pads will no longer be a chore with the Pro5000R's. No more fiddling with a hammer, punch, or pliers. AP’s bridge bolts pop out easily with a 5mm hex wrench and a 7mm socket. It will take you longer to pull off the wheel than it will to change pads. Less time futzing around in the paddock, and more time driving= fun.







The CP9668 caliper even takes things a step further in terms of convenience, and includes two bridge options as standard. You can use the fixed bridge, or you can install the included quick-change spring clip. To open the spring clip, you just squeeze and lift. Changing pads has never been faster or easier!



Discs- AP Racing Competition J Hook


The AP Racing J Hook discs in our system are the epitome of endurance racing components. They will hold up extremely well to any abuse you plan to throw at them. These discs have been proven time and again in professional racing, winning many races and even championships (ALMS, Rolex, Grand Am, etc.).

Two-piece Floating Design with Aluminum Hat


As is the case with most metal, iron brake discs grow substantially when heated. As it is heated, a disc expands radially, increasing in diameter and circumference. One-piece disc designs run into problems when this occurs. Look at the picture below and imagine the disc is being heated on the track. As the disc expands, the outer edges of the disc are pulling away from the center of the disc, but there are no built-in provisions to allow for that expansion. The edges of the disc therefore pull, lift, and distort, which is called coning. Now imagine that disc vertical on the car, running in your caliper. Coning directly impacts the brake pads’ contact with the disc, leading to uneven wear and tapering, and even a long brake pedal.

Two-piece discs on the other hand, compensate for the expansion of the disc as it heats. This is accomplished by building ‘float’ into either the disc itself, or the disc hat/bell. In this case, the float is in the disc. If you look closely at the picture below, you can see that the mounting holes for the hat attachment bobbins are not round. They are an oblong shape. These channels allow the hat mounting hardware to slide as the disc is heated and expands, allowing the disc to run true in the caliper without distortion. That means less distortion, stress cracks, and pad taper.











Mounting Hardware and Anti-Knockback Spring Clips

If you look closely at the mounting hardware we use in our Competition Kits, you’ll notice a few details that are often overlooked in lesser products. These components are specially made for their intended purpose. These are not cheap bolts found at your local big box store. They are custom made in the USA for Essex and AP Racing, and they are the exact same components we use on professional racing products.

As discussed above with regards to the piston springs, knockback can be a serious issue when tracking a car. In order to help control the lateral motion of the disc, which pushes the pistons back into the caliper, we use an anti-knockback spring clip on every other disc attachment point (on a ten bolt disc there are five spring clips, while on a twelve bolt disc there are six). These spring clips help keep the disc hat and iron ring in alignment, while still allowing the disc to expand and float radially. As an added bonus, they prevent the hat and iron disc from rattling and making noise.




Hat Design

Floating two-piece discs also have the added benefit of reducing heat conduction to the hubs and bearings, decreasing wear and tear on these costly components. The disc hats themselves are manufactured from 6061 heat-treated billet aluminum, with a hard anodized coating. This material was specifically chosen for its strength at high temperatures, as it will be in direct contact with the searing hot iron discs. The hats feature scallops on the underside, to allow for heat evacuation along the outer disc face once installed.




Internal Vane Quantity and Quality


The internal vane design on AP J Hook discs is quite a bit different vs. OEM-style discs and other brands of aftermarket discs. Many OEM discs feature a pillar vane design, which can be thought of as a group of posts or pillars connecting the two disc halves together (see pic below). The pillars are not organized linearly from the outside to the inside of the disc, and turbulence is created as air flows through and among them. Pillar vane discs are therefore not particularly well suited to heat evacuation. The goals of a pillar vane design are disc face stability for low nvh (noise, vibration, harshness), and a low cost of production. Pillar vanes are non-directional, and the same part number is used on both sides of the car (again for cost reduction).

Other OEM discs feature a straight, non-directional internal vane. While that type of vane flows more air than a pillar, it does not move nearly as much air as the directional vanes featured in AP Racing's discs. Having directional vanes means that AP Racing discs are handed. There is a unique left disc and a right disc in each pair, and they cannot be swapped from side-to-side on the car. The orientation of the vanes is optimized to spin in a certain direction, pumping the maximum amount of air possible through the disc. The shape of these internal vanes is also optimized to promote smooth airflow.




In addition to having a superior internal vane design, AP Racing discs have far more of them! Most aftermarket discs have 30 to 48 vanes. After extensive CFD and thermal stress analysis, AP designed the J Hook's with a high vane count (typically 60 to 84 depending on application). Having more vanes increases airspeed and heat transfer through the disc, reduces air recirculation between vanes, and reduces deflection at the disc face. Compared to an OEM-style disc or competitor's 48 vane discs, the 60+ vane discs are less prone to coning, distortion, and cracking, while providing less brake fade, reduced judder, more even pad contact, and a longer service life.
Below is a comparison of a one-piece OEM pillar vane disc and an AP Racing two-piece J Hook. A few things to note in these pictures: The AP Racing disc has a much wider air gap between the disc faces, allowing considerably more airflow into and through the disc. The uniform, directional vane design also contributes heavily to superior airflow.







Most of the cooling air that enters a brake disc comes from the back side of the discs, particularly if brake ducts are being employed. The top disc is an OEM pillar vane. The second disc is an OEM dual-cast disc (which is technically a two-piece disc). The bottom disc is the AP Racing J Hook. Which of these discs do you think will flow the most air? While the OEM discs have narrow inlet port and/or obstructions blocking the disc vanes, the AP Racing disc offers a clear path for cooling air to enter and flow through the disc. The result is significantly cooler discs that are less prone to cracking and wear.






Exclusive AP Racing J Hook Slot Pattern


When you cut a slot or drill a hole in a disc you impact heat transfer. The area around the slot or hole acts as a cool spot when the disc heats up, which is not ideal. Ideally, heat is distributed uniformly around the disc so it can be hit with the cooling air that is pumping through the disc, radiate outwards away from the disc, etc. Cool spots create stress risers and increase the likelihood of the disc cracking. They also cause the face of the disc to distort unevenly, leading to uneven pad deposits, vibration, and judder.

The OEM discs avoid this problem by simply leaving the face blank. While the risk for NVH goes down, so does the pad bite and feel of the disc through the brake pedal. Competitive aftermarket offerings typically have straight slots, which tend to leave cool spots across the disc face between the slots.

During exhaustive R&D testing, AP's J Hook design was found to create a constant pathway of evenly distorted material on the face of the disc. The hooks are spaced out as evenly as possible both around the circumference of the disc, as well as from the inside edge (where the hat attaches) to outer edge, with a slight overlap to promote even heat distribution/distortion. In addition to reducing cracking, the even heating of the disc also helps provide an even transfer layer of pad material on the disc when you bed them in.

Additionally, the J Hook slot pattern produces a greater number of leading edges for the pads to bite into vs. a traditional curved slot pattern, and particularly a plain-faced disc. While this may lead to slightly more whirring or scraping noises from the discs when applying the brakes, the benefits of more even heat distribution, less propensity to crack, cleaner pad material transfer during bed-in, and more bite far outweigh the slight increase in NVH for the serious enthusiast.




Complex Metallurgy Developed Through 50+ Years of Experience

AP Racing has been designing brake components for more than 50 years. They've had their components on cars that have won more than 750 Formula 1 races! On any given race weekend, AP J Hook discs can be found on 75% or more of the NASCAR Sprint Cup grid. AP has learned from these experiences, and have developed a proprietary iron alloy with extreme durability, designed specifically for what you intend to do with it (flog the hell out of it). The primary objectives with OEM discs are simple: they must be cheap and easy to produce. The design objectives for these two products are vastly different.

Disc Burnishing/Bedding Service

If your brake discs aren’t being properly prepared for abuse prior to flogging them on track, you’re exposing yourself to potential judder, vibration, and cracking issues. We all know that prepping your pads and discs at the track can be difficult. Doing so wastes time during the first session of the day, and it's a hassle and potentially dangerous for other drivers as you go through the procedure. Track time is expensive and tough to come by. The more time you spend behind the wheel performing an elaborate bed-in procedure, the less time you’ll spend doing hot laps. Performing the procedure on-track also limits its repeatability. You can't control what's going on around you with track conditions, other drivers, etc., and many track configurations don't really lend themself to the constant start/stop/start required to do the job properly.

Essex is now offering a solution via our professional burnishing service. Previously reserved for our professional racing customers, we are now offering our retail customers the option of having the discs in select Competition Brake Kits pre-burnished at our factory. We burnish thousands of discs for the top racing teams each year. After countless hours of experimentation, and extensive feedback from the top drivers and teams, we can consistently squeeze the most reliable performance out of AP Racing's discs. The procedure is incredibly repeatable, as it is performed on a computer-controlled machine by experienced technicians.

Initially, we will only be burnishing our brake kit discs with the Ferodo DS1.11 pad compound, but will likely expand the program to other compounds in the future. If you decide to select this option, the discs in your brake kit will arrive covered in a beautiful transfer layer of DS1.11, ready to drop on the car for instant abuse. The cost of our burnishing service is $50 per disc ($100 per brake kit).
Please note that the pads you receive will not be pre-burnished. In other words, the pads and discs do not have to be a matched set burnished together to reap the benefits the procedure has on the discs. In other words, we will burnish the discs in the pad compound you choose, they just won't be burnished with the exact set of pads that will arrive with your kit.

Watch a brief video of our disc burnishing service here.




Reasonable Replacement Cost

Let's face it, no matter how good a brake disc is, it's still a consumable item. They're no different than brake pads or gasoline. You beat them up until they crack to pieces, then you throw them away. If replacement iron is too expensive, you're always driving in fear, waiting to shell out big bucks for a new set. Despite having the most expansive set of features on the market, the J Hook's are completely affordable.

Going to the track is expensive! Event entrance fees, hotels, fuel, and tires all add up. While you obviously want the best product available, you can't afford to pay a small fortune for something you're just going to destroy. You can buy a cheap set of discs for every event, have relentless heat issues, and find yourself constantly swapping them out. When you do the math, the long-term value of the AP J Hook's is tough to beat. You'll enjoy all the benefits without breaking the bank, and you'll spend more time driving and less time wrenching.

Elite level teams choose AP Racing discs because they know the work has been done to provide the best available product at any price level. The AP J Hook is a direct derivative of AP's vast racing experience. You can buy with confidence knowing that you're getting the best product available at any price point. A note of caution however: the J Hook design is often imitated, and there are a number of lesser quality imitations on market. Before purchasing, make sure you are getting an authentic AP Racing J Hook.

Caliper Brackets & Hardware

Caliper brackets for our kit are machined from heat-treated 6061 T6 billet aluminum, and hard anodized, ensuring strength and durability. All included hardware is of aircraft quality, and identical to what we use in professional racing. One of the nice features of our brackets is their cutaway design, which allows for the snug fitment of many currently available brake duct kits.



Spiegler Stainless Steel Brake Lines

Our Competition Kits include a set of the highest quality stainless steel brake lines available. Spiegler lines have a wide range of features not available in competitive offerings. Below are just a few. For complete details please visit the Spiegler page on our site.



Last edited by jritt@essex; 10-01-2015 at 03:49 PM..
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      10-02-2015, 02:11 PM   #43
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drooling alright.......

definitely needs a rear one to match this piece of art (cosmetically).
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      10-02-2015, 06:58 PM   #44
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Ordered the CP9660!

CP9668 will not clear 19" competition ZCP wheels unfortunately - they will clear an APEX EC-7 18"x10" ET25 wheel though with plenty of room, and 9660 caliper clears both with ease. Can't wait to see this mounted in person!

Some pictures of the CP9668 template against my wheels:

Competition wheel - really, really close - heat expansion might get the two to contact - need a spacer, I think.


Apex EC-7 wheel - plenty, plenty of room.
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