Gauging Interest:New for 2017 Essex Designed AP Racing Radi-CAL Competition Brake Kit
 

Hello Gents,
I hope all is well in 86 land. I just wanted to check in and gauge interest on a new product idea we've been kicking around. We've been working with AP Racing over the past year on the development of a new Radi-CAL Pro5000R caliper. It's an ultra-lightweight (4.8 lbs.) forged four piston, with ventilated, domed-back, stainless steel pistons with anti-knockback springs. As with all of our calipers, it uses a commonly available pad shape. These calipers are the state-of-the-art right now, and have had a huge impact in pro racing. There isn't anything else like them in the market at any price. You can learn more about them in this blog post: The AP Racing Radi-CAL Story.

https://www.youtube.com/watch?v=SQjq...ature=youtu.be

Below are some shots of the new caliper when used in its rear configuration (CP9449/50/51). The front version will look essentially the same with different piston sizes.
http://cimg5.ibsrv.net/gimg/www.corv...c06f695219.jpg
http://cimg7.ibsrv.net/gimg/www.corv...067561a875.jpg
http://cimg8.ibsrv.net/gimg/www.corv...b94e699611.jpg
[IMG]http://cimg9.ibsrv.net/gimg/www.corvetteforum.com-vbulletin/800x533/80-20161121_cp4994_pro5000r_7_3_726ec621***aa3071eb48 6bbe80937643e4c89cd.jpg[/IMG]
http://cimg1.ibsrv.net/gimg/www.corv...a9cbcdf9b3.jpg
http://cimg2.ibsrv.net/gimg/www.corv...cf9526ffdf.jpg
https://s28.postimg.org/mnlmvy23h/Pr...R_Family11.jpg

Sploosh.

- Andrew

Jeff, how would this compare to the Sprint and Endurance kits? That's an interesting piston design; are there any negatives with having the leading edges scalloped like that?

It's about time!!! :D

Okay...now here's the part we need help with. We're trying to decide what size/type of disc to match up with these incredible new calipers. We've been discussing various options internally. I'd like to know what people want. Regardless of what size we go with, it will be a stout AP Racing J Hook disc, just like we sell in our current Sprint and Endurance Kits.

Option A: The same 299x32mm disc that is being used in our venerable Sprint Kit. At first glance this disc seems small, but we've won tons of races, events, set records, etc. all over the world with this tough little disc. One of the best features is that is very inexpensive to replace. We've had them on plenty of cars with 350 or more WHP, and it's very rare that anyone can fade them on the 86 chassis.

Option B: Increase the disc size to 310x32mm. This setup would offer a little more thermal capacity, without a huge weight penalty. It only weighs about a half a pound more than the 299mm disc in Option A. Wheel fitment really wouldn't be impacted at all with this setup vs. the Sprint Kit. In some cases, wheel fitment would actually improve, because the spokes curve inward as they get closer to the hub.

Both of the above kits would likely retail for a price in the mid $2000 range. Maybe something like $2599, like our current Endurance Kit. I haven't run the final numbers yet, but it's likely going to be close to that number.

Option C: Increase disc size to 340x28mm. Because this disc is narrower (28 vs. 32mm), the weight is nearly identical to the two discs above, despite its larger diameter. Wheel fitment would definitely be impacted vs. our current Sprint Kit. Because the disc is narrower we'd be able to pull the caliper inboard a little bit. However, there wouldn't be as much wheel barrel clearance on 17's because of the larger diameter. The big difference with this one is that these discs are considerably more expensive. These discs would push the price up to the low $3,000 range.

At this point I'm leaning towards Option B. Given the amount of abuse our 299mm discs have proven capable of handling, I'm thinking a 310mm kit with the Radi-CAL would be the ultimate solution for about 95% of our customers. A kit in that configuration would weigh about the same as our current Sprint Kit (20 lbs. less than the OEM front brakes), while offering a bigger disc with a little more thermal capacity than our current Sprint Kit. The Radi-CAL caliper technology would provide superior pedal feel due to stiffness, and offer better cooling due to the body and piston design.

Please let me know your thoughts, and thanks as always for your input!:cheers:

Hahaha...OMG...you literally made me laugh out loud on that one!:party0030:

See disc options above in my second post for a comparison to our current kits. There are absolutely zero negatives to the scalloped/ventilated pistons, but lots of benefits. The scallops allow air to flow behind the pad backing plate and into the body of the piston. They help significantly with cooling the piston walls, brake fluid, and caliper body. The other sneaky-cool feature about the pistons in the Radi-CAL's is the domed back. Having a curved back significantly increases stiffness, and the pro drivers all noticed the change immediately when that design change was implemented on the Radi-CAL calipers in NASCAR Cup, IMSA, etc. The domed back gives better pedal feel. They also keep the same style anti-knockback springs used in the CP8350. The pistons in the Radi-CAL are just a more advanced design.

You're tellin' me brother! We've been waiting on these calipers for quite a while. They were a clean sheet design, and we spent a great deal of time spec'ing them out with the AP engineers. Fortunately, the final product was worth the wait. The first batch of rears is inbound, and we're launching rear kits for a whole slew of cars...e92 M3, F80/F82/F87 M2, M3, M4, C5/C6/C7 Vettes, Porsche 986/987, etc. We're still a little ways out on the front variant, but we want to plan accordingly and get the design work underway for an 86 kit if there is adequate interest. I'm assuming there will be, as these new calipers are Ridonculous! :D People freak out when they hold them in their hand for the first time...and then a little more after they drive them.

So this new caliper weighs the same as the CP8350-2S4L/3S4L in the sprint kit? Was hoping they were lighter....

Glad I've held off on doing anything for suspension and brakes yet....almost ready to begin making it ready for track use...

I'd be most interested in Option A... dropping unsprung mass is a top priority to me along with as low consumable cost as possible.

Here are some other Pro5000R Radi-CAL kits we've designed on other cars to give you an idea of what they look like mounted up. Some of these are prototypes of the kits we are releasing over the next couple of months, hence the raw aluminum disc hats:
C7Z06
https://www.essexparts.com/storage/w...281cdf19_4.jpg

https://www.essexparts.com/storage/w...0fb052e5_3.jpg

e92 M3
https://www.essexparts.com/storage/wysiwyg/yIr0Vci.jpg

BMW M2
https://c1.staticflickr.com/1/519/31...417235bc_b.jpg

https://www.essexparts.com/storage/w...gPro5000Rb.jpg

BMW M4
https://s28.postimg.org/ods7xl1t9/m4front9668b.jpg

S197 Mustang
https://www.essexparts.com/storage/w...ro5000R_14.jpg

Shelby FP350S (soon to be released by Ford)
http://o.aolcdn.com/hss/storage/mida...5-img-2446.JPG


Nissan GT-R
https://www.essexparts.com/storage/w...RPro5000Rd.jpg

Porsche 987 Cayman
https://s24.postimg.org/trkw0ejz9/987protoa.jpg

VW Golf GT Mk6 and 7
https://www.essexparts.com/storage/wysiwyg/GTI_BBKa.jpg

These aren't from the Pro5000R range, but they're all running a different variant of Radi-CAL, and they are gnarly cars...had to share. Some of these pics are from the Rolex 24 at Daytona last weekend.

Lexus RC F GT3
https://www.essexparts.com/storage/w...pg%20large.jpg

Carbon body before wrapping...
https://www.essexparts.com/storage/w...pg%20large.jpg

Porsche 911 RSR...took second in GTLM class last weekend.:thumbup:
https://www.essexparts.com/storage/w..._720x406x2.jpg

Okay...you can't see the Radi-CAL brakes in this shot of the 911 RSR, but I just had to post it.
https://www.essexparts.com/storage/w..._720x406x2.jpg

Corvette C7.R
https://www.essexparts.com/storage/w...lzakrrc7tx.jpg

BMW M6 GTLM
https://www.essexparts.com/storage/w...sto-farfus.jpg

Woah. JRitt: stop posting porn pictures. :)

I was at the Rolex 24 too, but brakes were furthest thing from my mind, other than getting shots at the brake zone before the oval section:

https://photos.smugmug.com/Cars/Raci...tCbhgWF-X4.jpg

Too bad the lexus team didn't do that well, pretty cars though. Still need to find time to sift through all the photos and video I took.

Just take my money.

@JRitt you're a man of your word! For the rest of you, Jeff and I exchanged e-mails a few days ago when I inquired about about the possibility of developing a Radi-CAL Pro5000R kit for our cars, and he said he'd survey the forum to gauge interest.

Obviously, I'm on board! Option A or B would work for me, but I think option B offers the broadest appeal. At around $2,600 I can put a deposit down on a kit now.

Prior to 'Radicalizing" their calipers, each successive generation of AP Racing caliper would gain something like 3% stiffness due to further design optimization. With the patented Radi-CAL design, AP was able to increase stiffness over 30% vs. a conventional caliper of the same basic form without adding any weight, and in many cases reducing weight. That is without resorting to any exotic materials. In engineering terms, that is an almost unbelievable accomplishment, and a massive leap forward! After their first round of testing, the improvements were so dramatic that their engineers actually had to recheck their data to make sure there wasn't an error in the results.

If you look closely at the caliper, there really isn't a way to make it much lighter. Look at all of the gaps and voids where material would normally be, like the big holes between the pistons. The Radi-CAL calipers are basically a skeleton. They provide the structure and support only where required, and any superfluous material is stripped away.

The only other possible way to further reduce weight without changing the materials used would be to make it a monobloc and eliminate the four bolts that hold the two caliper halves together. That's what AP does in NASCAR for example, and the calipers look like the one below. In that case however, the caliper becomes painfully time-consuming and costly to machine/manufacture. They also use titanium pistons to further reduce weight, but they cost $5,000 each, and that's just for the caliper!

While the monobloc is inherently lighter due to the lack of through-bolts, that doesn't automatically make it any stiffer, which is a big misconception among many enthusiasts. With the monobloc, in many cases you must remove the caliper to change pads, which is obviously far from desirable to most of you on this forum!

https://www.essexparts.com/storage/wysiwyg/_DSC0083.JPG

Sweet! I'm jealous...would have loved to have went. Nice pic!

Thanks! We discussed this project in our weekly product planning meeting. We had touched on it before, but the calipers were just too far out on the horizon, and we had a stack of other projects that we needed to get done first. I think the time is ripe to bring the latest tech to the 86 market. We just haven't had the proper components to do so. Our Radi-CAL kits are becoming the gold-standard in every market we enter with them. Whatever we end up with, I can promise you that it will be by far the most advanced option on the market, and unlike anything else at any price.

I admit that for the events I do, the only thing that's really of value is weight. Don't get me wrong, pedal feel and such matters a lot, but the only compelling reason for me to switch would be weight loss over the Sprint kit. Fade isn't on the map.

Same weight and more wheel options would be nice, less weight would be crazy...
That said, same weight as Sprint with the capacity of the Endurance would really be something. Buying new today this would probably get my money over the Sprint setup in A or B. I'd take Sprint if it's still lighter, since it's also less expensive.

Also, you mention rear configuration; I assume that we'll not see a rear package for this car but, can you confirm?

C

Like option B.

Thanks for the feedback gents. If we go up to the 310mm disc with the Radi-CAL, we're going to wind up within half a pound of the Sprint Kit, except with more heat capacity. The CP944X Radi-CAL is significantly stiffer than the CP8350, and it will provide a substantial feel improvement. The domed-back pistons will contribute to this benefit as well. Cooling will also be improved considerably. As described previously, the ventilated pistons allow the pistons, fluid, and caliper body to run cooler. Also, the design of the Radi-CAL caliper body itself lends itself to superior cooling, since air can flow around and between the pistons. The outer contour of the Rad-CAL is a bit more sculpted vs. the CP8350, which should help with wheel spoke clearance. Additionally, since the caliper will move out slightly towards the wheel barrel, that will provide even more wheel spoke clearance. The 310mm spare discs would be the same price as the current 299mm discs.

Basically, if we go Option B, the new kit will do more than the Sprint Kit in numerous areas, while still weighing nearly identical. That doesn't even include bragging rights or street cred.;)

Jizz. I just jizzed. Many times

Wow, beautiful piece of kit! I would prefer option A, for maximum addition of lightness!

JRitt: btw, but how about such heresy as 16" or even 15" wheel fitment? :)
Hence i'd probably vote for smaller disk size.

Thanks for the explanation on the caliper design. So basically they have the same mass as earlier designs because of previous optimization, but the Radi-CAL design was not really a matter of modifing the existing design - it is entirely a rethink of the caliper using the same mass but redistributed and restructured in a way that dramatically improves stiffness and thermal cooling of the caliper. Got it....and fully on board with it. Was just hoping a little mass could have been removed in the process....would have been icing on the cake.

Question regarding fitment: so if a certain wheel fits the Sprint kit, then the Radi-CAL kit should have the same or better fitment even though it will have a wider caliper because its 'centerline' will be more inboard compared to the other calipers? The wheels I run have a 7mm clearance closest to the wheel hub according to the Sprint Kit template. I should expect the Radi-CAL kit to have about the same clearance as well with option A? Or would option B be needed for a similar fit (don't like the weight penalty though):

https://photos.smugmug.com/Other/TES.../i-QffnRM6.png

Gauging Interest:New for 2017 Essex Designed AP Racing Radi-CAL Competition Brake Kit
 

You're saying these give better feel than the Sprints?!?!? I am in love with my Sprint and Carbon Lorraine pad combo and can't imagine how it could be improved for feel.
My instructor drove my car at the last HPDE and said it was one of the best setups he'd ever driven.
Too bad I've already invested in the Sprints or I'd be in!
I might still be if you were to go for option A. I'm guessing they will have a different mounting hole pattern than the CP8350s?


Sent from my iPhone using Tapatalk

Heresy indeed! :p The 310mm disc should still fit inside many 15's, and no issues in 16's. We cram our 325mm disc in some 15's in circle track racing!

Precisely, you got it. The only way to save more weight is to go to exotic materials such as titanium through-bolts and pistons, or go to a monobloc design. All of those routes would drastically increase the price.

The aluminum disc hat we use on our 299mm disc can also fit our 310mm disc. We would likely retain that hat, so the offset of the disc won't change. It will sit in exactly the same location as it does now. I have to double check, but I believe the caliper offset on the Radi-CAL is also very similar to the CP8350. That means the caliper is going to be oriented very similarly to our current Sprint Kit relative to the spokes and wheel barrel.

If we went with Option A and kept the 299mm disc, everything would fit pretty much exactly how it does now.

Option B would only be a very slight change. Looking at your drawing, imagine lengthening the wheel fitment template 5mm towards the wheel barrel (going from a 299mm to a 310mm /2= 5mm radius increase). So if you move the whole template out 5mm out towards the wheel barrel, you'd be left 20mm of barrel clearance, and potentially gain a couple mm of spoke clearance on the inner spoke near the hub..maybe from 7mm to 9mm or so (depending on the angle of the wheel spoke). On those particular wheels, it looks like you may lose a little spoke clearance on the outside though...maybe you'd go from 15mm to 13mm, since the spokes start to curve back in as they get closer to the wheel barrel. You'd still have plenty of clearance everywhere though.

See my edited drawing below...I just took the template and slid it out to the left. I left a nub of the red line to illustrate how far I moved it. Please let me know if that doesn't make sense. Thanks!
https://s29.postimg.org/yieahw1nb/BR...BK_comparo.jpg

Thanks for the great feedback, and I'm glad you're still loving your kit! :cheers: We will be sure to investigate a caliper upgrade package for current Sprint Kit customers. Worst case you'd have to buy calipers and brackets. Best case, maybe just calipers. We'll do what we can to figure out a solution. Thanks again for the purchase!

There was another thread just posted asking about this exact subject.
http://www.ft86club.com/forums/showthread.php?t=115425

I know I'd be more inclined to sell a working Sprint setup than upgrade the calipers. Not that I have a compelling reason to sell, the Sprint really is excellent.

Unless... it's a 4 wheel upgrade. I assume it's still just front.

C

Option B, please & thank you.

Which kind of pad would these use? I'm only interested if Carbone Lorraine's lineup is available, but i guess that won't be a problem.

Option B sounds great. Any estimated timeframe for possible release? Was looking at doing the sprint kit in the next couple months.

The new four piston Radi-CAL uses a common pad shape that is available from pretty much every pad manufacturer in all flavors (including Ferodo, Carbone Lorraine, etc.). Pad selection will definitely be no more of an issue than it is with our current kits (which=not an issue at all).

Since we're just now talking about this one, I'd estimate it will be a few months before we are shipping a final product. I'll take a stab at it by estimating a possible May release??? There's a lot to be done between now and then.

Rear Kits

Based on the past five years of data, we know that a rear kit isn't necessary for the vast majority of our customers with an 86. The performance gains of a rear kit vs. stock are much lower than those achieved by adding a front kit on this platform. We have customers with all types of builds, power levels, and usage environments running our front-only systems all over the world without any issues.

Price is also major issue. How many 86 owners are honestly going to spend $5,000+ for a complete front and rear kit? It costs us a substantial sum to design and build these kits, and we need to justify those costs with a return on our efforts. Anything we would release would be top-shelf, and designed to solve problems. We would never implement a half-baked, 'budget' solution and suggest that our customers actually need them...from what we've seen, 98% of them do not, and we tend not to cater to hard-parkers. ;)

All of the above said, if there is enough real demand/need, we will build whatever people want.:thumbup:

A good thing for us poor european guys, is that rear BBK open the choice to more pads.
Especially when we can use same front and rear pads. It makes sourcing pads much easyer.

Pads are so expensive out there that we mostly have to buy in the US or Japan.
Even french pads (CL) are twice the price in France.

Hmm, didn't think of rear BBK for widening pad choice. Sounds valid reason for those that wish to save on wearables.

I'm in cjd's boat - largely interested in weight reduction, though I do intend to track the car once I've added some additional capacity to the brakes. The Sprint kit has been on my radar for awhile, though it is a bit further down the upgrade path at the moment (knee surgery isn't cheap!). I'd probably be willing to trade a pound or two for better tech, so mark me down as an option A or B kinda guy - but to be fair, you'd just be converting a Sprint kit sale to this.

Pad choice, ease of swapping pads, and brake feel are the reasons I would consider it... Though unless I get to the point I'm tracking and want the capacity, it's not realistically in the budget either way right now. I already have the Sprint...

I know it would be an expensive option up front, but suspect it would be worth it if I'm ever pushing that hard. I totally get why it may not be worth the development cost, and there are others on the market for those that really need a 4 corner setup.

That would be perfect. Means another set of stock rotors and pads, but they will be shot in May and then I get the summer off here in AZ to do the upgrade. Highly looking forward to it.

Thanks for the info.

So what would be the practical benefits over the AP Sprint kit, if I have yet to fade the sprints? I understand that it has more heat capacity and better cooling, but heat hasn't caused me any issues yet. Of course, I'm only at the intermediate level for now, so I'd imagine this kit would provide more benefit for a more experienced driver?

If rest of brakes decided to keep same - lighter/stiffer/better cooling calipers.

I'm in the market for either this kit with option B or the Endurance kit in the near future. I think I would rather have this option.

I would be interested in the B kit, and in the very near future as well. This is for a new full track build which is starting this Friday.

Two things I missed in the thread: Will the new setup with the 310 rotors be floating or fixed hats? Will the new kit get the brake duct attachment point that the endurance series has?

Option B/C. I've been going through several sets of the 299x32mm disc every year so I need a little more capacity.