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M2 Technical Topics > Suspension | Brakes | Chassis > Essex Designed AP Racing Radi-CAL Brake Kits for M2 Competition save 40 unsprung lbs!

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      12-20-2018, 01:48 PM   #23
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Summary:

Entire kit saves 40lbs

Entire kit costs $10k

Kit allows 18" wheels

Kit's caliper allows quick pad changes

(There's also two areas of thought with regards to caliper weight & design. Some would argue rigidity (eg a fixed bridge) is of greater benefit than the convenience of quicker pad changes. But will leave for another thread)

Going from OEM disc to aluminium hat type disc saves 90% of the 40lb total


Conclusion:

If you don't need to run 18" wheels, and spending 5 more minutes swapping pads every ~6 months is not an issue either; and you're after the weight savings primarily, then buy/find just aluminium hat type discs that work with the OEM caliper.

Literally a 90% of the benefit for 10% of the cost scenario.
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      12-20-2018, 02:17 PM   #24
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Quote:
Originally Posted by jritt@essex View Post
Quote:
Originally Posted by CosmosMpower View Post
Wait you need to remove the whole caliper to change pads on the stock caliper?
Yes. Here's what the N2H caliper looks like on top...fixed bridge. There's no way to remove the pads without taking the caliper off the car.



On the base blue brakes you can punch out the pins to remove the pads, and you do not need to remove the whole caliper. This is what cntzl mentioned. The pins are a bit of a hassle. I've had them on several cars and never liked them. In the pic below, you can see the blue standard caliper in the middle with the pins removed.



On the AP Racing calipers, you do NOT need to remove the caliper to swap pads. On the AP's there are little aluminum bridge pieces that pop out with hex head bolts. There are two bolts on the front calipers, and one on the rear. As noted, with our calipers it takes longer to jack the car and remove the wheel than it does to change pads.

Here's the top of the CP9660:


Our CP9668 front caliper (the one that takes the inch thick pads) was designed for quick pad changes during endurance races. As such, it comes with two bridge options in the box. The standard one that looks just like the one on the CP9660 above, and a quick change spring clip. With the spring clip, you don't even need tools to remove the pads! You just squeeze the spring clip, lift, and it swings up out of the way so you can pull the pads.



Jeff, do you have the spring clip option on the 9660's or are they only on the 9668's? Either way, they look easy to swap pads over 👍🏻👌🏻
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      12-20-2018, 03:11 PM   #25
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The way I personally see it is that I've wanted to do regular track days for a long time and now that I can comfortably afford to buy an M2 Comp with additional modifications I want to get it set up so I can abuse the car knowing that the brakes won't fade and that I can swap the pads out easily for road use in between track days.

Yes, it's a lot of money to spend in addition to the car itself, but I'm not planning on selling it any time soon and I plan to get my money's worth out of the AP setup along with other mods 👍🏻
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      12-20-2018, 03:45 PM   #26
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Quote:
Originally Posted by mikeahso View Post
Summary:

(There's also two areas of thought with regards to caliper weight & design. Some would argue rigidity (eg a fixed bridge) is of greater benefit than the convenience of quicker pad changes. But will leave for another thread)
I don't think that comment needs to be left for another thread. Have you actually read any of the details on the Radi-CAL calipers? They have a huge stiffness advantage over conventional style calipers, which is why they are the dominant choice in top level racing. Added mass is one way to increase stiffness, but clever engineering is alternative solution. All else held equal, during the development of the Radi-CAL AP was seeing 30+% increases in stiffness vs. conventional caliper designs. Check out this video/article:

https://www.essexparts.com/news-blog...-radical-story

Quote:
Going from OEM disc to aluminium hat type disc saves 90% of the 40lb total
That's actually a gross exaggeration. On the front, the weight savings split is more like 65% of the savings is from the disc, and 35% from the caliper. On the rear, the weight savings split is about 50% disc, 50% caliper.

The AP calipers have ventilated stainless pistons (run cooler) with a domed back (increased stiffness), and anti-knockback springs (save the typical driver major pucker factor when their pedal drops halfway to the floor heading into a brake zone after a series of S turns). The Radi-CAL calipers also allow for far more air to move in and around them, which allows them to run cooler overall. That means less fluid boiling and replacement.

You can get pads in just about every racing compound under the sun for the AP Racing calipers, which can't be said about the OEM shapes. The CP9668 caliper also allows one to run a 25mm thick pad.

I understand that you may not like the price, but I don't think your dismissive statements or 'conclusion' about our product are in any way fair or remotely accurate.
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      12-20-2018, 03:47 PM   #27
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I always liked AP Racing brakes. The design is completely inline with my approach to brakes: buy the best over engineering brakes money can buy.

I am considering AP Racing brakes for my 2017 BMW 440i Gran Coupe (RWD). What are the part numbers for front and rear kits: red calipers, J hook rotors?
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      12-20-2018, 03:57 PM   #28
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Quote:
Originally Posted by cfm56d7b View Post
I always liked AP Racing brakes. The design is completely inline with my approach to brakes: buy the best over engineering brakes money can buy.

I am considering AP Racing brakes for my 2017 BMW 440i Gran Coupe (RWD). What are the part numbers for front and rear kits: red calipers, J hook rotors?
Thank you very much. We unfortunately don't offer a fitment for your car (swee ride though!). Sorry about that!
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      12-20-2018, 04:59 PM   #29
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Quote:
Originally Posted by jritt@essex View Post
Quote:
Originally Posted by cfm56d7b View Post
I always liked AP Racing brakes. The design is completely inline with my approach to brakes: buy the best over engineering brakes money can buy.

I am considering AP Racing brakes for my 2017 BMW 440i Gran Coupe (RWD). What are the part numbers for front and rear kits: red calipers, J hook rotors?
Thank you very much. We unfortunately don't offer a fitment for your car (swee ride though!). Sorry about that!
I had no idea. I recall AP Racing Radi-Cal and Radi-Cal II brakes were widely available for F3x models.
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      12-20-2018, 05:17 PM   #30
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This is an alternate to the Carbon Ceramic Setup?
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      12-20-2018, 06:51 PM   #31
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1m zcp wheels would look great on that car..
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      12-20-2018, 09:21 PM   #32
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Hmm if only Brembo was this open about their products online it would be so much easier to learn about brakes. I would love to learn more about what I am about to put on.
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      12-20-2018, 10:39 PM   #33
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Great post and awesome stuff from AP.

My comment below is negative sounding, but that is not the intent... I know a ton of R&D $ has been invested and it's a niche automotive company etc.

From my perspective for an average dude doing track days, the ROI, not carbon, I struggle to justify the cost (20% of a 2016 M2) and performance gains unless you are a pretty experienced driver. Plus removing a BMW caliper takes 5 minutes to swap pads, yes annoying but... I'm not not enduro racing at a professional level.

At the end of the day the look/design and performance are A+ and if I had spare change I'd throw down on a set.
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      12-21-2018, 01:57 AM   #34
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Do you do them for the F80 M3 front and back? Will you plan to do them for the G80?

How would you compare to Mov'it? Their brakes are massive.
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      12-21-2018, 02:41 AM   #35
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Why would you pick these over a Stoptech setup that's anywhere from 1000-1500 less?

Looking for a technical answer, not a salesy one.

For the record, I've used Stoptech on another platform and loved them.
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      12-21-2018, 05:03 AM   #36
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I've been Jonesing for these since I first saw the thread on Bimmerpost back in 2016 (maybe early 17). I don't think the rear kit was available back then but I put them on the mod list however, they have always been below the cut line $$$ wise.

I was under the impression that Brembo was the parent company of AP (maybe AP started out as a UK company which was then acquired by Brembo at some point)?

I got my first in-person look at them earlier this month at the Essen Motor Show (poor iPhone pic below) but they do look 'the business' and they certainly are light weight.

Does Essex do additional design or modification to the 'stock' AP Calipers or disks?
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      12-21-2018, 05:08 AM   #37
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Yes, AP is a subsidiary of Brembo. Picked them up in 2000.
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      12-21-2018, 05:28 AM   #38
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If you need a lightweight brakes kit you can also choose from the big range of aftermarket Brembo brakes, it's just a matter of how much you want to spend
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      12-21-2018, 06:16 AM   #39
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Quote:
Originally Posted by cfm56d7b View Post
I had no idea. I recall AP Racing Radi-Cal and Radi-Cal II brakes were widely available for F3x models.
We (Essex) are AP's integration experts and distributor for their competition line of products in North America. The Radi-CAL II is a road caliper, and we don't deal with those parts. It's likely that a road car distributor or reseller in the US makes a kit for that car with those calipers (which is what I'm sure you saw), but we don't unfortunately.

Quote:
This is an alternate to the Carbon Ceramic Setup?
Absolutely. Carbon ceramic setups can be nice for the street, but they still can't touch an iron system for the track. Our systems provide most of the weight savings of carbon ceramic discs without all of the headaches. We have a ton of Porsche GT3, Corvette Z06 and ZR1, Camaro, Audi, Ferrari, Lambo, McLaren, and other owners replace their CCM disc systems with our iron ones (pics below). Some points on carbon ceramic from our website:

Iron vs. Carbon Ceramic Brake Discs

In the past few years, Carbon Ceramic brake discs have become increasingly popular on high-end sports cars as either standard equipment or as a factory installed option. Although expensive, they're a great choice for a car that is used exclusively on the street. They save a large amount of unsprung weight, they don't generate much brake dust, have low NVH, and they may even last longer than the rest of the car! For the avid track enthusiast however, they're typically not the best choice.

On the racetrack, repetitive stops from high speeds generate considerably higher brake disc temperatures vs. what could ever be legally or sanely achieved on the street. Various manufacturers producing the current crop of carbon ceramic discs claim to match iron disc durability on the track, but our experience tells us otherwise. While they may be less resistant to warping or deformation at repeated elevated temperatures, the biggest problem with carbon ceramic discs is that they tend to oxidize at track temperatures, showing rough surface eruptions on the disc face. In some cases the oxidation is terminal (chopped fiber discs), and the discs must be scrapped once it occurs. In other cases (continuous fiber discs), the discs can be resurfaced, but only a limited number of times and at a high cost. Most carbon ceramic discs are measured in terms of minimum mass, rather than the traditional minimum thickness used to measure iron discs. Once the minimum mass is reached, the carbon ceramic disc is trash.

Below is an oxidized carbon ceramic disc. Notice the dark spots in which the surface is flaking off / eroding. When your disc looks like this, it has become a $2,000 paperweight!

Other Potential Pitfalls with Carbon Ceramic Discs:

Low airflow- If you look at a specific car model that offers both iron and carbon ceramic discs as an option, the carbon ceramic discs will almost always be considerably larger in overall dimension, with a specific emphasis on a tall radial depth (distance from outer disc edge to inner disc edge). Whereas an iron disc uses a web of directional internal vanes to speed airflow through the disc, most carbon ceramic discs rely primarily on their large surface area to radiate heat into the air surrounding the disc. Hence, the tall radial depth.

Expensive and limited range of compatible brake pads- There aren't many brake pad options with carbon ceramic discs. The pads must be compatible with the specific disc material being used, and if they aren't, they can destroy the discs in a hurry. Since brake pads are a very personal choice to most track junkies, carbon ceramic discs don't provide many options for the driver to chase a desired feel. Also as noted above, carbon ceramic discs tend to be very tall radially, which means very large brake pads are required. In the world of brake pads, price is usually directly proportional to size: Bigger = more expensive.

Poor feel- Experienced drivers will tell you that cast iron discs provide superior pedal feel due to less compress-ability. Some drivers find that carbon ceramic discs feel soft or abrasive at lower temperatures, but feel like stone with little modulation once they heat up. Feel and the resulting confidence is rather important when hurtling towards a guardrail at 150mph!

High replacement disc cost- Carbon ceramic replacement discs can be hideously expensive. If you do wear out or damage a disc, it can cost thousands of dollars to replace each one. When running carbon ceramic discs hard on a racetrack, the odds of having to replace one or more of them increases exponentially vs. if you only drive your car on the street.

Damage-prone- Many manufactures suggest covering their carbon ceramic discs when handling them, so they are not chipped or fractured. One knock when changing a wheel can destroy a disc. Additionally, some chemical wheel cleaners or abrasives used in car detailing can damage carbon ceramic discs.

Splinters- Carbon ceramic discs shouldn't be handled with bare hands, as they can leave carbon splinters in the skin.

Greater sensitivity to burnishing/bedding-in- Most manufacturers have an explicit, and sometimes intricate, set of instructions for bedding-in their carbon ceramic discs. Iron discs can typically be prepared via a simple series of stops from 60-80 mph with the brake pad of choice.

Carbon Ceramic is NOT Carbon/Carbon

At this stage you may be saying to yourself, "But I saw that the XYZ professional race cars were running carbon brakes at the track." The carbon brakes currently being used in professional racing are carbon/carbon (abbreviated C/C), which is actually a different material vs. the carbon ceramic discs used on road cars. The carbon ceramic brake discs on road cars are a Carbon Ceramic Matrix (CCM). In recent times many professional racing series (F1, ALMS, IRL, etc.) have switched to carbon/carbon brake discs in an effort to reduce weight. Carbon/Carbon is an outstanding lightweight material for racing, but requires heat before it starts to generate usable friction. As such, they're completely ill-suited to a typical morning commute in a road car!
Iron Disc Benefits

So what can AP Racing J Hook iron discs do for a car previously equipped with carbon ceramic discs?

Increased airflow and slower heat transfer to other brake components- AP Racing J Hook discs have a unique, high-count vane design that promotes airflow, heat evacuation, and rapid cooling. They don't rely on a large surface area to cool via radiation. The iron discs will move more air than your carbon ceramic's, and as a result they won't heat your brake pads, caliper pistons, and brake fluid up as quickly. You'll be able to run longer sessions without brake fade, and you'll enjoy the confidence that comes along with them. They'll also make any brake ducts that you have on the car more effective and useful.
Huge range of compatible brake pad compounds- Iron discs will open up a much greater range of available brake pads. You'll be able to achieve a different feel, and tailor your brake setup depending on your needs and environment, whether that is running an AutoX or the most demanding racetrack in your area. You'll also likely be paying less per brake pad set than you were previously, and your pads will last longer.
Inexpensive spare discs- You'll no longer have to spend thousands of dollars when it's time to replace your discs. AP Racing J Hook's typically only cost $300-500 per iron disc ring, so you won't have to stress about anything happening to them. They're inexpensive enough that you can always keep a spare set on hand, so you won't have to worry about any brake-related downtime when you're out at the track.
Durability- Iron discs can take a beating. You can stash your spares in your race trailer, and you won't have to worry about handling them, covering them, dinging them, or chipping them when changing your wheels.

As you can see, although iron discs do come with a slight weight penalty, they're still the smart choice if you run your car hard on the racetrack. They're the obvious solution that has been proven countless times on tracks around the world, at all levels of motorsport.

Over the last few years we have replaced a LOT of carbon ceramic discs. Now brace yourself for car/brake pron from some of our customer cars.






















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      12-21-2018, 06:27 AM   #40
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Quote:
Great post and awesome stuff from AP.

My comment below is negative sounding, but that is not the intent... I know a ton of R&D $ has been invested and it's a niche automotive company etc.

From my perspective for an average dude doing track days, the ROI, not carbon, I struggle to justify the cost (20% of a 2016 M2) and performance gains unless you are a pretty experienced driver. Plus removing a BMW caliper takes 5 minutes to swap pads, yes annoying but... I'm not not enduro racing at a professional level.

At the end of the day the look/design and performance are A+ and if I had spare change I'd throw down on a set.
Thank you very much, and no worries at all. Our systems are a significant investment, and we get that. That's why I was pointing out the long-term economics of the situation earlier in the thread. Many times people don't think about resale value, selling their stock parts, residual value, etc. It all boils down to what each individual wants out of their car.

Quote:
Do you do them for the F80 M3 front and back? Will you plan to do them for the G80?

How would you compare to Mov'it? Their brakes are massive.
Yes, we have complete front and rear F80 kits, and yes we will have them for the G80 as well. Here are some comments and pics from a customer who recently installed them. This member is here on Bimmerpost. You can probably track him down over in the F80 section. https://www.essexparts.com/news-blog...ical-brake-kit

"First track day at Buttonwillow Raceway Park (BRP) with the Essex/AP Pro5000R. These brakes are awesome!!!I couldn’t be happier. I came from the Brembo GT w/ Type 3 rotors. Just FYI, I’ve had Brembo BBKs in my last 3 M3’s. I’m not going back. Cheers!"





Here's an F82 pic I particularly like:



I would have to see a specific product from Mov'it to do any type of reasonable or valid technical comparison. From what I've seen in the past though, I've never viewed them as a technology leader. The calipers I've seen were big as you noted, had a lot of pistons (I think I saw a 12 piston at one point?), but they didn't have anything particularly ground-breaking about them.

Last edited by jritt@essex; 12-21-2018 at 08:55 AM..
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      12-21-2018, 06:57 AM   #41
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Quote:
Why would you pick these over a Stoptech setup that's anywhere from 1000-1500 less?

Looking for a technical answer, not a salesy one.

For the record, I've used Stoptech on another platform and loved them.
How our Radi-CAL Competition Kits compare to, and differ from, StopTech Big Brake Kits is a question we receive quite often. Below I've put together a comparison between the two brands. Pretty much everything below applies to our system vs. most OEM brake systems, and all of our competitors' aftermarket kits vs. our Essex Designed AP Racing Radi-CAL Kits.

For reference, I was the sales manager at StopTech for 4-5 years back in the early to mid 2000's when they were just getting their legs. I was there when they did their first BMW brake kit designs (the owner drove an e36 M3). I also ran the StopTech ST-60 system on my C5 Z06 while I worked for them, so I'm intimately familiar with their products. The StopTech system is very nice with high quality parts. When we designed our Essex/AP Racing kits however, we set out to make every component in our kits lighter, stiffer, more durable, and far more effective than anything else on the market.

Calipers

Core Design

The StopTech ST-60 is a basic, no frills, conventional design from roughly year 2003. It was designed to be as versatile as possible to service a wide range of vehicles from sports cars to trucks out of the same casting. Over time it has undergone some changes, moving from a casting to a forging, losing a little weight, etc. It is a quality road caliper. The Trophy version was conceived in roughly 2009, originally as a 'special edition'. It is the same caliper with a bit of fat trimmed, and the option of running AKB springs at an added cost.

The Pro5000R Radi-CAL's, CP9660 and CP9668, were designed in 2014 using AP's collective knowledge gained from roughly 7 years of Radi-CAL designs in Formula 1, NASCAR Sprint Cup, DTM, etc. You can read about The Radi-CAL design philosophy here, and the huge impact they had at the elite level of racing. The primary benefits of the Radi-CAL design are:
• Massive Stiffness Increase- A 30+ % increase in both static and dynamic stiffness 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.
• Efficient Packaging- The wide, asymmetric caliper profile and internal porting allows the caliper to fit into tighter spaces.

From a technical standpoint, the Radi-CAL design makes everything else on the market a bit of a dinosaur. They are the current state-of-the-art in caliper design, and the gold standard in elite racing.

Anti-knockback springs

AP Racing has them, StopTech doesn't, unless you pay extra for their Trophy Kit. As noted earlier in this thread, people severely underestimate how valuable these springs are. After going through S turns, you'll have a much lower pucker factor in the next brake zone with the springs installed.

Piston type
StopTech= cast aluminum
AP= Domed-back, ventilated, machined stainless steel

Stainless is far superior at keeping heat out of your brake fluid. The domed-back provide added stiffness and superior pedal feel, and the ventilation also allows them to run cooler. StopTech will tell you that SS pistons are a problem because they expand at a different weight than the aluminum caliper body when they are heated, which can lead to piston cocking and problems. That is complete nonsense. Every serious racing caliper on the planet runs either SS or titanium pistons. I've been with Essex/AP Racing for ten years now, and we've sold thousands of calipers with SS pistons in the aftermarket at this point, and we have NEVER had an issue with a piston cocking, etc. Literally, not once.

Weight
AP Racing CP9660 Pro5000R weighs 6.2 lbs. without pads. Our CP9668 (which is wider and takes a 25mm thick pad) weighs only 6.8 lbs. The StopTech ST-60 weighs roughly 8.8 lbs, and the Trophy version is something like a pound lighter.

Dust Boots
StopTech uses a street caliper, and as such it uses dust boots. AP Racing Competition calipers have none. If you've ever run dust boots on the track, you'll find that they burn up and cause a big mess almost instantly. Their only value is if you're driving on winter or debris/dirty roads and you don't want to have to wipe your pistons off during a pad change. As soon as they go on track and get destroyed they essentially lose all value.

Seals
Both calipers have quality, high temp seals.

Hydraulic protection
StopTech has an external crossover pipe for fluid, and outer bleed screws, while the Radi-CAL Pro5000R's have internal porting and don't even have an outer bleed screw. This feature protects the hydraulics from track debris, and when you're swapping wheels. No chance of knocking a bleed screw or bending a crossover tube.

Materials and Bridge
The caliper bodies on the ST-60 and Pro5000R are both high quality forged aluminum parts. The bridge on the AP uses two bolts and is easier to manipulate. On the CP9668, a spring clip quick-change bridge option is also included, which reduces pad change time to about six seconds. You squeeze the spring clip and lift...that's it, no tools required! With four bolts, the bridge on the ST-60 can be a hassle to get in and out. On my Z06 I had to wrestle with it a bit to get it seated properly, particularly after it was heat-cycled numerous times.

Pad choice/cost/size

Both the ST and AP calipers use an old AP Racing pad shape and have tons of pad options. The radial depth on the Pro5000R calipers is 54mm vs. 51mm, so you get a tiny bit more pad volume with the AP's. Thickness on the ST-60 and CP9660 is 18mm, but our CP9668 offers 25mm thickness if you're endurance racing, or if you're just lazy and don't like to change pads as often!

Stainless Steel hardware
Both calipers have high quality stainless steel hardware.

Footprint/size
In addition to weighing much less, the CP9660 has excellent wheel fitment, partially because it has no outer bleed screws and it is tapered on the corners. It fits inside OEM wheel options without a spacer. Despite being considerably wider, the CP9668 is still a compact package and will fit many wheels. On the M2 Competition the wider 9668 fits the OEM wheel without a spacer. Because we use a 372mm diameter disc, we can still fit inside 18" wheels, and our disc is about as large as you can squeeze inside most 18's.

Finish
StopTech= painted. Look pretty, but will not look as good after hard use. Paint and powdercoat tend to change color dramatically at track temps. If you're driving through road salt however, they will be better protected than anodized.

AP Racing= anodized. Do not color shift nearly as much. An added bonus is that they also look 'racier' (like what you see on full-blown race cars).

Rebuild Service
Essex offers a lifetime professional reconditioning service. You can send your calipers to Essex and have them rebuilt by the same techs who service NASCAR and IMSA teams. I'm unsure of ST's procedures, policies, and prices on rebuilds at this time.

Discs

Design
Both companies offer high quality discs for the kits in question. Discs from both manufacturers are quality castings that are crack resistant and will last a long time under heavy track use. That said, the StopTech discs are a more pedestrian 48 vane design, whereas the AP Racing discs have 84 vanes (nearly twice as many). That means more disc face stability and higher airflow. Our discs also have the patented J hook face slot are the #1 choice at the elite level of motorsports (NASCAR, IMSA, DTM, Aussie V8, Super GT, etc.).

Size/Mass/wheel fitment
The discs in the front StopTech kits are typically either 380x32mm or 355x32mm. Our front discs are 372x34mm. We have the largest disc that will fit behind most 18" wheels. Our discs are thicker, have nearly twice as many vanes, and you'll have more wheel fit options than you will with a 380mm disc.
StopTech 355's with hats weigh about 18 lbs., their 380's weigh about 21 lbs. Our 372's weigh approximately 21 lbs. assembled.

Spare iron price
StopTech 355's are $345 each, and 380's are $375 each, and our 372mm discs are $399. We believe that the tiny premium for our disc is more than offset by the technology and longevity embedded in our discs.

Disc hats
Both have a quality design and are made from aircraft grade aluminum. Both are optimized for weight and airflow.

Disc Burnishing
For $100, Essex will burnish your discs with the pad compound of choice. That means you don't have to fiddle around with bedding-in your discs, or worry that you're doing it properly. Our patented burnishing machine and process make sure it's done properly every time. We burnish thousands of discs each year for pro race teams. StopTech does not offer this option/service.

Brake Lines
Both systems came with a high quality set of brake lines, but the Spiegler lines in our kit are the highest quality available. They feature stainless fittings with a unique swivel system that prevents twisting and kinking.

Other Factors

Initial Purchase Price

StopTech ST-60/380mm kit=$3695
StopTech ST-60/380mm Trophy Sport Kit= $4495 (if you want dust boots, it's more)
Essex Designed AP Racing CP9660/372mm kit= $4399
Essex Designed AP Racing CP9668/372mm kit= $4799

Obviously I'm a bit biased, but it's almost inconceivable that anyone would pay a similar amount for the aging StopTech technology vs. our latest AP Racing Pro5000R offerings. The Pro5000R Radi-CAL kits are a step beyond the ST kits in every facet. Yes, our kits are initially ever-so-slightly more expensive than the basic ST-60 kit. However, there is a huge difference in the level of hardware you're getting in each kit. Our setup is the same as what is delivered on factory-built racecars from Audi, VW, BMW, Ford, etc. Every component is designed to be stiffer, lighter, and more durable than anything else on the market. There's nothing even close.

Long-term Running Costs and Value
As noted above, spares for our kits are nearly the same price as StopTech. The difference is, ours will be burning at a slower rate. The initial purchase price difference is made up over the course of ownership, and it is definitely made up at resale time.

As with most premium brands in any segment, AP Racing products hold their value better competing brands. As noted previously, our brake kits change hands for a nice chunk of their original price. People know that even after a considerable amount of abuse, the components are going to hold up and keep performing. They also know they can have Essex service them and make them good as new again for a reasonable price.

Brand/Reputation/Panache
StopTech has a solid reputation for supporting grassroots racers, providing quality parts at an obtainable price (I like to think I was actually a large part of building that reputation early on ). Lots of lower-level racing series use ST products successfully.
AP Racing is the best of the best, with over 700 Formula 1 wins on their brake components. Just about all factory BMW race cars run and trust AP Racing. They have the most cutting-edge products, and when people see the AP Racing logo, they think "the best."

Aesthetics
Other than not being available in fancy colored paint, I don't think it's a remotely close comparison as to which kit looks better. Behind the wheels, 380mm discs effectively look nearly identical to a 372mm. The radius of the 380mm disc means it only sticks out 3mm closer to the wheel on either side vs. a 372mm, which is negligible visually. The J Hook slots also look way cooler than a straight slot.

Service
Often overlooked, but a critical aspect of ownership when you're out flogging your brakes every weekend. Essex has some of the best customer service in the industry. We jump through hoops to help our customers, and we treat our retail customers the same way we treat our OEM and professional racing customers. Read reviews of our systems, and something you'll always see are comments about the lengths we go to ensure a positive ownership experience. We have been in business for nearly 35 years, and we always have a live human picking up the phone during regular business hours.

In summary I'll say that I'm not trying to bash StopTech. I have nothing against them, and they make nice products. I also still have friends who work there. That said, time has moved on. We now have superior technology and offerings available to the average enthusiast that hadn't even been conceived 10 years ago. The initial purchase price of our AP systems is a higher, but so is the value of what you're actually getting. If you want the best, I believe we have it. The image below from our SEMA booth gives a pretty good idea of what AP Racing components accomplished last year in racing...those are all championships, and there are many others. It was more of the same in 2018...AP Radi-CALs won the NASCAR Sprint Cup championship this year, Le Mans GTLM class on the Porsche 911 RSR, etc.

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      12-21-2018, 07:14 AM   #42
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I've been Jonesing for these since I first saw the thread on Bimmerpost back in 2016 (maybe early 17). I don't think the rear kit was available back then but I put them on the mod list however, they have always been below the cut line $$$ wise.

I was under the impression that Brembo was the parent company of AP (maybe AP started out as a UK company which was then acquired by Brembo at some point)?

I got my first in-person look at them earlier this month at the Essen Motor Show (poor iPhone pic below) but they do look 'the business' and they certainly are light weight.

Does Essex do additional design or modification to the 'stock' AP Calipers or disks?
Thanks! Yes, Railgun is correct. Brembo owns AP Racing. Brembo is fortunately wise enough to allow them to compete freely in the market however, which keeps the technical innovation alive at both companies.

In some instances we do make modifications to the calipers themselves. For example, the calipers in the Porsche 991 GT3/RS brake kits pictured above have some mods that we perform. We work with AP on new caliper designs. We provide our 'wish list' and subsequently work through the details until they become a reality. We design all of the brackets and disc hats in-house at Essex. We also draw up unique discs for AP Racing to produce. If you look at AP's website you won't be able to find many of the products we offer, as they are exclusively designed for our use in our North American market. We actually have an AP Racing engineer who has worked out of our office in Charlotte, NC for the past 15 years. AP has been a brilliant long-term technical partner of ours, and they design and build incredible products.
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      12-21-2018, 07:44 AM   #43
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Great stuff, Essex.

I used to fight overheating, fade, uneven wear, and caliper discoloration with the OEM BMW M blue brakes. All that went away once I put the AP front BBK on.

When you’re headed to a tight turn at the end of a straight going 145mph, any fade at all is a very scary feeling. Never an issue now with my AP’s.
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      12-21-2018, 08:57 AM   #44
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Great stuff, Essex.

I used to fight overheating, fade, uneven wear, and caliper discoloration with the OEM BMW M blue brakes. All that went away once I put the AP front BBK on.

When you’re headed to a tight turn at the end of a straight going 145mph, any fade at all is a very scary feeling. Never an issue now with my AP’s.
Thank you very much! We're glad they are getting the job done for you. Your statement succinctly sums up how we feel about the topic! My hunch is that you feel like you got your money's worth?
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