Howard Coleman

iTrader: (6)

jim,

just a few thoughts on you and me and others w big front brakes.

the FD has 68% front 32% rear braking force at the tires.

if you add the AP 5200 caliper in the front and don't change the rear you are at 74% front and 26% rear.

if you add the later model 12.2 inch rear rotor to the AP front you are at 73/27.

should you wish to get back to the right balance but greatly (over 50%) increase brake torque at the wheels...

pedal your stuff. sign up for option 3. while it still is not firm, i expect the fronts will be 355 mm 14 inches and the rears will be 340 13.375. 6 pistons front and 4 in the rear and you are back to 67/33.

i am sure you are aware of the bolt on emergency brake calipers... i am going to come up w something else. perhaps a Line Lock..

howard

94RHDFD

iTrader: (3)

Would this not work?

Howard Coleman

iTrader: (6)

yes but.

it looks hoky (IMO) and masks a good bit of the rotor from cooling.

hc

ARD T2

iTrader: (22)

I'll be giving Warren a call when i return to work on the 2nd and get an update as to what is really in the works to be produced.

I'll refrain from making assumptions as I've been gone for a week and there have been several posts since i left.

I personally would like to see these options as a distributor for Racing Brake and what I believe will have a market.

All two piece rotors:
1. US Spec Front and rear Rotors: should be available NOW.

2. JDM 99 Spec Front and Rear rotors with Caliper Brackets for US Spec Calipers: ALLEVIATES THE NEED TO PURCHASE 99 SPEC CALIPERS. However if someone already has 99 SPEC calipers they now have an TWO PIECE rotor OPTION

3. LARGER REAR ROTOR for Coleman's or Jimlab's setup. Not sure if the 99 spec rear would suffice for that. Obviously an aftermarket rear caliper with proper piston diamters would be needed. DOWNSIDE: i'm 95% sure you will lose the EBRAKE function.

I honestly don't think it's realistic to expect a 2 or 4 piston rear caliper that will retain the use of the ebrake. Unless RB can produce this caliper I haven't seen an affordable option out there. Not sure if the demand would justify the cost of engineering and production.

That's my mini synopsis and my personal opinions. I would love to see a rear brake caliper that could retain EBRAKE Function but be universal enough so that it can be used on several different applications of vehicles. Naturally there must be a reason why this hasn't been done by virtually any manufacturers.

If you can, either hc or jimlab, please list either in this thread or another what aftermarket companies produce a rear caliper that can retain manual ebrake function. Would be much appreciated.

The only other intermediary solution i can see is the adapting of a hydraulic ebrake to retain ebrake functions with aftermarket rear calipers. THis is an option i'm looking into and would work. Just not sure of the "plumbing" and how DIY this would be for the laymen.

Happy New year,

Rishie

Be back on 2nd and have a shitload of reading to catch up on. I apologize if I have stated the obvious or repeated a prior post.

TeamRX8

iTrader: (2)

Actually that's my RX-8 package so thought I'd drop out of my usual lurk mode here and throw in my experience with RB. Though it's been many years since I last owned/ran an FD I can say that the OE RX-8 brakes are IMO superior to the FDs OE brakes. In fact, the general concensus before RB offered their kit was that a BBK for the RX-8 is a total waste of $$$. Admittedly, I didn't expect to get any real braking performance increase.

Due to the NA Renesis' limited power potential I was more interested in chopping off weight, which came to a 24 lbs. decrease off the front end using their 13" 2-pc rotor w/4-piston fixed caliper BBK (OE is 12.8" w/slider caliper) and another 5 lbs drop off the rear using their 2 pc rear rotors. They made the same decision with the RX-8 to preserve the OE rear caliper due to the e-brake issue. I had some of the same hesitations, but eventually accepted it.

I 've been etxremely pleased with my RB experience. First, the quality of their product has been nothing short of excellent, both in build and in operation. Second, I worked closely with Warren & Steve @ RB the way that Howard now is when we found that their initial front BBK, which worked well with OE and many HP wheels, had a caliper interference with a popular Enkei wheel for the RX-8 (RPF1, 18 x 9.5, 17 lbs @ $300 ea). I took a few measurements and determined that there was enough clearance to offset the hat/rotor deeper and move the caliper further inboard with a new bracket. I supplied the dimensions to Warren. A few weeks later I received a new set of rotor hats, hat hardware, and caliper brackets from RB, all the same finish quality as the originals. Everything bolted up and fit perfectly with the Enkei wheels. They now offer that package as an additional kit.

FInally, the icing on their great value/quality and superior commitment to customer service is how the RB system works. Many people said the F/R balance would be off; not true, it's great. I find the kit to offer much more finess at the limit than the OE brakes ever did, which provides fine braking control during extreme trail-braking maneuvers. I'm etxremely satisfied with my RB system. I highly recommend not jumping to any premature conclusions. The results will speak for themselves.

TeamRX8

ARD T2

iTrader: (22)

Thanks for your post Team. Your work with RB has been phenomenal, i have followed it on the RX8 board. I can't commend you gentlemen enough in helping to provide a test basis for companies like RB to produce products which we know to be in demand. Without true racers like yourself many of these options would have never existed. Kudos and hats off to you guys for providing technical info and proof of performance.

I did a similar thing as you with my Endless Calipers but SUX cause they won't clear those Enkeis. arghhh. I'm stuck with Multipiece wheels for now and don't want to fork out the cashola for TE37's.

turbogarrett

iTrader: (1)

This would be a great option for the many of us who already have the 99 rears

jkstill

iTrader: (11)

I would not recommend Revolution Brake. This is a spinoff from Precision Brake.
Though the website for Precision Brakes suggests that the change is to address customer service issues, they will need some time to prove themselves.

For reasons why I do not recommend them see my thread on an FD front brake kit from Precision Brakes: Precision Brake Experience

jimlab

And the details on my experience with them from earlier this year.

https://www.rx7club.com/showpost.php...postcount=4156

damian

iTrader: (2)

great thread howard!!!

I have been through the paces with the brake setups on both my FDs and done a lot of trial and error with my race car.

I am learning a lot and this thread is another great one.

Here are some 'brake' threads that I have posted in thge past that have at the least, some fun pictures of differetn brake parts :-)

Rs/Rz brake upgrade on all 4 corners, and upgraded rotors:
https://www.rx7club.com/forum/showth...=damian+brakes

My track car came with the BigRed kit on the front and jspec rears, however I wanted to have the hats remade in aluminum and change to a floating rotors (directional). I used colman rotors to do this setup:
https://www.rx7club.com/forum/showth...=damian+brakes

Making rotor ducting:
https://www.rx7club.com/forum/showth...=damian+brakes

Brake rotor comparison:
https://www.rx7club.com/forum/showth...=damian+brakes

I now have a set of stoptech front calipers and rotors that I purchased in an effort to solve some brake issues in a rush for nasa nationals. There is a longer story here with my race car brakes, but ill leave that out of this post. I will eventualy post a new thread on that kit with nic pics and info on the rotors, calipers, hats, et, et. I also have a full manual brake system now with balance bar.

https://www.rx7club.com/forum/showth...=damian+brakes

BTW howard, did you get my last pm?

Howard Coleman

iTrader: (6)

RacingBrake needs your input asap

warren is in the late stages of finalizing a front/rear brake upgrade for the FD which will use the OEM calipers, E brake and will greatly improve braking performance.

he needs your input as to aftermarket wheels and caliper clearance versus the OEM wheel.............

please post your experience as to any clearance issues w aftermarket wheels and calipers.

if you have been following this thread you may remember that after developing the RX8 one of the owners ran into a clearance problem w a set of Enkies. Warren made a deeper hub and changed the caliper mounting bracket to accomodate the wheel.

here's a recount and picture:

https://www.rx7club.com/showpost.php...&postcount=130

ideally, it would be great to sidestep the problem so please do post any info you might have on this matter.

thanks,

howard coleman

Eggie

Howard, Rishie should have all the relevant info on the Enkeis. The RPF1s with +45 offset should be the tight ones, but they are supposed to clear RS/RZ brakes. Would be excellent if Warren could provide the same clearance or more.

wanklin

iTrader: (2)

Howard, You may want to PM Rich. I recall him having BBK clearance issues with his FM5s.

Kento

Noted here in this thread.

GooRoo

iTrader: (4)

Just for anyone interested, I've found a few things to read to understand the physics of the braking system:

This is a link to the Grassroots Motorsports Magazine article that everyone should read. Easier to understand, less formulaic.

http://www.teamscr.com/grmbrakes.htm

Here's a couple StopTech whitepapers with more exact physical formulas.

Short Version:
http://www.stoptech.com/tech_info/fo...g_dynamics.pdf

Longer Version:
http://www.stoptech.com/tech_info/Th...%20Systems.pdf

This one is interesting for this discussion as well. They lay out a bunch of reasons why you might not want to do a 'caliper move-out' kit like we have been talking about with Racing Brake. However I find it interesting that every one of their points will be addressed with the RB setup. Nice work Racing Brake!

http://www.stoptech.com/tech_info/St...Out%20Kits.pdf

Here's the rest of the StopTech whitepapers:

http://www.stoptech.com/tech_info/te...e_papers.shtml

RacingBrake also has some nice info on their site:

http://www.racingbrake.com/main/product_knowledge.asp

I also made a excel spreadsheet that allows you to play with the various parts of the braking system and see what effect it would have on the FD. I used it to play with the setups that are on Damian's car and my car and it was pretty interesting stuff.

So far I haven't taken into account the cooling side of the rotor equasion. Racing brake has a nice article ( http://www.racingbrake.com/main/rotor_vane_design.asp ) about the various types. The formulas for that are not as easy to come up with though, since the cooling effect of the rotor is not a simple constant or function...

Anyway, If I can clean that spreadsheet up enough to be presentable I'll post it here.

sdoow

Well done GooRoo and good sense why RB is not welcome by other brands. I just post a reply at G35 (Infiniti), where we are not a vender, neither we monitor the board on regular basis but you can just see how RB OE caliper kits are accepted and welcome there.
http://g35driver.com/forums/showpost...6&postcount=37

Our OE caliper kits are not “Move Out Kit” as they implied. See following link and learn how RB OE caliper kits are different from those move out kits.
http://www.racingbrake.com/main/oe_c...it_compare.asp

Learn more on what is an OE caliper kit.
http://www.racingbrake.com/main/oe_c...it_compare.asp

We also build aluminum caliper kits but note the difference:

· We always consider and provide the rear as we offer the front brake kits.
· In addition to aluminum caliper kit we also offer one piece; two piece and OE caliper kits and even our upgrade from OE to aluminum kit is incremental and progressive i.e. we use the same big rotors.
· We lay the fact and explain to customers in “true” plain language for their own choice to fit their need and budget.
· Our brake system is always designed around OE set up in which we believe a true brake balance can only be achieved by proportional increase the torque arm which is the rotor diameter. Piston sizing is meant only for fine tuning and can never deliver the same result as rotor sizing.

Just think if a brake balance can be accomplished by changing the caliper piston sizes then why would those motor companies spend so much more investment in providing big rotors for the rear as the front rotors are enlarged.

We don't believe shortcut although our kits are much more difficult and cost more to build but we can still keep our cost low because we spend money on development and tooling while they spend more on sponsorships and marketing.

Warren - RB

gracer7-rx7

iTrader: (16)

Yes, please do. Pm'ing u my email just in case.

1st to 3rd

Rishie, I'm confused. Are you suggesting that RB will make a 32mm wide rotor to work with the RZ calipers?




Warren, I agree with you post above and applaud your efforts. If I read correctly, the future Racing Brake caliper will use the same 324x22/24 rotor? Is a thicker rotor ring a possibility?


Agreed. Can't please everyone, but if you could fit within this wheel, I believe you can please most.

Howard Coleman

iTrader: (6)

"Are you suggesting that RB will make a 32mm wide rotor to work with the RZ calipers?"

i appreciate your confusion... since RB is in a developmental process w the FD many options have been considered and the process may have caused the confusion. the FD picture is coming clearly in to focus as represented by the options table you post above.

the first high impact product will be the front and rear 2 piece rotor upgrade using caliper relocation brackets to retain the proper OEM longitudinal brake bias. rotor thickness has been set so as to use the maximum allowed by the OEM calipers.

there are additional FD options that may become available which would not use the OEM E brake and may be more track oriented.

it is important that you not discount the vast upgrade performancewise that the four 2 piece rotor package will provide. w the proper pads you will have brake performance similar to the NSX, that also used the relocated OEM calipers, and was outbraking lots of cars in a long road race at Daytona a month ago.

i am not affiliated w RB but do have a sense as to where the RB FD project is heading.

please don't hesitate to ask further questions.

howard coleman

sdoow

Jesse brought in his RX7 yesterday and we measured the front caliper and found out it’s impossible to have a bigger rotor as OE caliper curvature is 300 mm only.



So there will be no OE calipers BBK for the front, but don’t be too disappointed just yet as this type of OE caliper was a mass production model made by Sumitomo with leg (side) mount to the spindle which tends to flex under high temp and hard braking. Serious racers usually upgrade to radial (top) mount caliper for better rigidity and performance. For example EVO and Sti racers are replacing Brembo calipers (same as Sumitomo type) with RB’s 4 pot caliper brake kits primarily for performance reason not for size.



Our two piece rear OE caliper BBK remains as a good companion (although may not be perfect) for people already have BBK in the front (like AP 5200). I believe the current unbalance is more caused by the rotor size differential - 13” front (BBK) and 11.6” rear (OE) than the piston size, so by replacing RB’s rear BBK and using aggressive race pads should substantially improve the current unbalanced setup.

With our rear BBK as the base we are sizing up our 4 piston caliper to essentially maintain the same brake balance of stock. This front BBK can be used to upgrade the stock or replace AP BBK if, after installing our rear BBK, the overall performance is still not satisfactory. Here is our updated matrix:



racingbrake.com

Kento

Oh well, I guess that makes the price go up.

But I like the fact that the RB radial-mount caliper is lighter than stock, and I understand the concept of radial-mount calipers, as all racing motorcycles (and the vast majority of production sportbikes) have gone to that setup. Warren, I am willing to pay from upgrading the whole assembly, but I guess my main concern is the overall disc size of the kits you will be offering. Moving to an RB caliper probably opens up the design constraints quite a bit, but I'd rather not go through the hassle of trying to sell my Fikse FM-5 wheels if at all possible. My FD will not be a "track dawg" car, in that while it will see occasional track days, that will not be its primary purpose in life. Which is the primary reason why I want to keep the rear OE caliper/e-brake setup in my brake upgrade plans, and am not really interested in an "ultimate" monster-size race setup for the front.

ARD T2

iTrader: (22)

Hi Warren,

That kinda sucks, but it was a good idea.

IN THAT CASE I WOULD STILL LIKE TO HAVE YOU PRODUCE THE SAME ROTOR DIMENSIONS AS THE 99 SPEC CALIPERS SO PEOPLE HAVE A TWO PIECE OPTION AND JUST SOURCE THE 99 SPEC CALIPERS WHICH WILL HAVE THE CORRECT CURVATURE.

Is this possible? I assume we need to source some 99 spec rotors so you can ensure the offset of the rotor hat is not different.

Thanks, rishie

ARD T2

iTrader: (22)

What i'd like to see Mr Warren:

1. US Spec 2 Piece Rotors - AVAILABLE on site
2. 99 Spec 2 Piece Rotors - Not available, but can be made without caliper bracket. Just rotors.

3. 4Piston BBK From RB - Already planned for production.

I still believe the 99 spec Rotors in 2 piece format would be a great seller. This is a very common upgrade for the RX7 guys. Now they can just simply buy the calipers and RB 2 Piece rotors. You mentioned that you have the Rotor rings already so that should be a quick production matter.

Thanks, Rishie

M104-AMG

iTrader: (8)

With RB's own caliper, I'd like to see a FRONT caliper & rotor kit that fits under the 16-inch stock wheel.

If you can get almost 13-inch front rotors under the stock wheel with a Wilwood setup, I am hopeful you could do the same with RB's calipers & rotors instead.

This should be PLENTY for most track dawgs . . .

:-) neil

Howard Coleman

iTrader: (6)

i was really surprised to find i could actually mount an OEM FD wheel to my AP5200 w 13 inch rotor setup. it would have taken 30 minutes w a hand file and would have worked. i agree that fitting the RB 4 piston up front w the bigger rotors should really be worked to fit stock wheels.

howard coleman