^ HP+'s are sad IMO and could be part of the problem under severe use, but the description sounds more like a binding piston causing beveled pad wear rather than overheating, which is really hard to accomplish, even on track with stock brakes and decent pads.

All four rotors have the exact problem/wear pattern.

There was another thread I was following when the member had a shop changed hir rear pads and he mentioned that it was heating up, "... poured water and the water was sizzling on the disk brake." I'll find the link.

Oh, and I should have mentioned it before, this is because of track day use.

EDIT: I didn't experience any brake fade, or any performance issues. I'll post some pictures later this afternoon.

The shop didn't bother to adjust the handbrake cable?

That was my initial thought, it was close to a year ago and haven't been back to see what the cause was in that thread.

Thanks for looking and the thoughts.

Here are two pictures of the brakes. All four look the same so I have counted out instalation errors (unless I really screwed up :lol2: ) and manufacturer defects.


There is about an inch of what the rotor is supposed to look like on the inner part of the rotor and then on the outter part it looks glazed or something. The brakes worked great!


This is the front left

Attachment 230320

This is the rear left

Attachment 230321

Hey Scott,

First of all, your track weekend looked like a lot of fun. Can't wait to come back and run ORP with you guys. Some day...

Is this the first time you've had HP+ on the track? Just curious if you've had these on the car before without issue.

The outer ring looks exactly like what happened to me when i paired Racing Brake rotors with Carbotech pads. I didn't know this until after the fact but there is a well known issue with RB rotors and Carbotech pads. They are simply not abrasive enough to keep the rotor free of pad deposits at high temps (Racing pad selection and brake pad deposit - RacingBrake.com). It looks like a similar thing is happening here.

You've always been a good driver but from the last few videos i've watched of you I can tell you're getting really good :). You may want to step up to full on race pads. After trying an assortment of dual purpose and mild track pads i switched to dedicated track pads. It's made a world of difference in braking performance, feel, pad life and my confidence in the braking zones. I've really enjoyed the Hawk DTC-60's in the front with HT-10's in the rear and right now i'm really enjoying Cobalt Friction XR2 in the front XR3 in the rear. Carbotechs had great performance characteristics but like i mentioned i had a bit of a pad/rotor mismatch and sold them off after two track days. I prefer the Hawks and Cobalts to the Carbotech based on braking characteristics alone.

Now that your rotors have bad pad deposits on them are you experiencing any vibration at slower speeds? When this happened to me it took a week or so but the pad deposits started causing really bad vibrations when i was just driving around town.

Like others have said it may be time for a rebuild of the calipers. Its odd the inside is smooth but i suppose that could still be down to an install error or something funky going on with the HP+. If you want to clean the pad deposits off and try new pads all you need to do is get a set of racing pads. When i switched from the Carbotechs to the Hawk DTC-60/HT-10, my rotors looked almost exactly like yours do. A few hard brakings from ~70mph and they were clean as a whistle. Oh yeah, and i did it at night and the red glow from the pad deposits burning off was worth it on its own. I wish i had it on video because it literally lit the whole road up on either side of the car from the burning embers :FIREdevil

Thanks man!!! :wavey: And yeah, you need to get out here!

August was the first time I wasn't stock (except I finally got a seat in Feb woohoo!!! How nice it is not to be thrown around.) I ran the HP+ at PR on the 22nd, but I took it easy because I had changed my alignment settings to a more aggresive setting and things were much more twitchy than before. I had also just put the HP+ pads on and the initial bite still had me a bit unnerved. I wasn't expecting that much of a difference. So I was about 2-3 seconds slower so I didn't end up in a hill :lol2:

I'm not sure if I noticed the rotors at PIR, but I know I was hard on the brakes on the two straights. And then I definately noticed them ot ORP and I was way harder on the brakes than the last time I was there, also knocking off 4-5 seconds. Still couldn't keep up with dondo and it was his first time at ORP :cussing: haha The brakes were solid though. And I am glad I switched brake fluid (GS610,) because I had been boiling the cheap stuff last year.


I'm not experiencing vibrations, but they are singing, and as I drive around town the outer ring is starting to become cleaner/shiny. On a rebuild, what exactly do you change?


I'll need new pads very soon so I'll be in contact with you. Never thought I'd burn through a set of pads in a month. Thanks for the info!

This is addressed to justjim only.
I was wondering what is your background. You seem to know a lot about breaking. I can not afford a BBK, so I am about to build my own. I have all the machinery to cut any bracket and metal what so ever, but mostly is going to be aluminum. I just purchased 6 pistons front calipers off of a 2010 Z06. I got them both from eBay for $270. I am looking for the rear ones now and the front & rear rotors. I am aware of all the changes that I have to do but I am willing to try it. I LOVE TO PROVE MY FRIENDS & FAMILY MEMBERS WRONG. I am also going to use the same size wheels that the Z06 has, 19X10 front and 20X12 rear. Yes I am getting a custom build wide body kit, and also I am welding the back doors.
I hope you can give me good insight and facts. I do not care for people's opinions and taste, It is my car and I got my own taste, sweet or sour is mine and America is a free country.

Your abs won't like those calipers.
your suspension won't like 19 and 20" wheels.

Good luck.

For F8S RX8. I haven't been on this forum for over a year. My RX8 is for sale, it's running good but has 120,000 miles on it and I wanted to try a car with more grunt before I get old so I bought a Holden Monaro (AKA GTO). The RX8 still makes me feel like I am putting on a spandex body suit that fits me like a glove and it drive like it knows what I'm going to do before I do it. The GTO makes me feel like Mad Max.

To answer your question, I'm 59, I'm a hydrogeologist with a Master of Science degree. I've had a life long interest in endurance racing and sports cars. I started tracking my Acura RSX and immediately came up against braking inadequacies common to FWD cars. I have a mechanical background and I talked to a lot of knowledgeable people with track experience to find out what works, and most importantly I tested what I heard and read on the track so I could see what worked and what didn't.

Eventually I moved on to tracking the Mazda RX8, and then successfully racing a Mitsubishi 3000GT in the Chumpcar series (7 top ten finishes, 2 seconds, and 2 firsts). I've focused a lot on braking with tracking my personal cars and even with the Chumpcar, because it the biggest bang for the buck on the the track and street brakes usually are inadequate at the track when pushed.

To summarize my personal experience. As I just said above, almost all street brakes are usually inadequate at the track when pushed. However, that doesn't mean the brake design is necessarily inadequate. Track brakes don't work well on the street and vice versa. Same for tires, tires that work well in the snow and potholes don't race well and slick R-compounds won't hold up or stick on cobble stones. The primary deficiency in street brakes when swithing to the track is either pad compound or rotor diameter. Pad compound selection is always a trade off between grip, longevity, noise, dust, cost, pedal pressure, and toxicity. Many cars can be successfully tracked even on R-compound tires with just a change to the proper pad and I count the RX8 as a classic example of this. It has excellent stock brakes. For the street I used stock RX8 brakes (pads and rotors) although I had ducting which may have helped. Pad change and tire change, and sway bar setting change and the car was good for the track.

Specifically to address your plans. There is nothing wrong with your project in principle. If you are smart, careful, and pay attention to detail, what you plan could work and you may achieve a working brake system. If your plan is to create something that works and show your friends you could do it you will likely be successful. If your plan is to make a braking system that stops shorter than the stock system, and works well at the track under racing conditions, you may find this to be a lot more complicated than it seems and I would put money on not accomplishing that task.

In general I would suggest that the parts you have selected are mismatched for size (calipers, rotors, and wheels and tires) for optimum performance. I say this not knowing the actual piston diameters of the Corvette calipers or the rotor diameters, etc.

My only advice is to take some baseline measurements before you execute your plan (stopping distance from a variety of speeds and conditions) and compare them when you are done. It would also be good to track test the car before and after (lap times).
Good luck and post the results for the benefit of everyone else. I don't know everything.

Very nice post thanks. I'm due for new rotors and pads this helped a lot

Hello everyone and sorry if my question might seem stupid to you ..

The thing is .. I live in Europe ( Romania ) .. and it`s really really hard to get good aftermarket parts in this region for a RX8. I am looking to change my rotors this summer ( maybe an upgrade ). I am not looking into BBK .. I just look for some good rotors for my 8. My car is stock .. 2004 ( 6 gear manual ). Maybe a Caliper upgrade also. Could you please recommend me smth. good ??

P.S. I don`t wanna go OEM because they rip your wallet at the dealership.

Could anyone direct me to the best rotors and break pads I should re place the stocks ones on my rx 8? Thanks!

Just street daily driving? or other??

hello.. im having problem with my 8.. i did a diagnose on it it it came up C2778 (sensor power supply failure) seems to me it didnt indicate which one of 4 is messed up.. or is it the calipers i need to deal with? i noticed when im braking/panic braking i had to pivot the wheel a lil bit to the left just to get the car straight on the highway. pls help...

OEM shims w/ AXXIS ULT Pads?
 

Hello folks. Since AXXIS Ultimate pads were mentioned a couple of times in this thread I thought I'd ask here...

I have a set of the Ultimates on the front, but my mechanic did not re-use the OEM shims. The pads seem to have an "integral" anti-squeal shim, but it looks like just a sticker on the back of the pad. Right now they are too noisy, and I'm thinking that putting the OEM shims back will help. I would like to confirm that the OEM shims will work with the AXXIS pads without dragging on the rotor?

Also, is there a way to buy just the shims without the pads, or the side clips (like in the attachment kit F1Y4-33-29Z?)?

Thanks!

You can buy the 'hardware kit' from the dealer or elsewhere consisting of the shims and clips, don't think the shims are avail separately..

Hey guys, I hope some people still lurk here. I was wondering if anyone has had any experience with Power Stop brake products. I found a set of rotors and pads, that seem decent, for a steal! So... I was wondering if that's because I'm lucky, or if they suck. Anyone heard anything about them?

Unless you track or are a serious autocrosser they should be fine. If they are used I suggest you get them re-surfaced.

Thanks for all this informations it is much appreciated! Will be back to look for information at a later date.

I have a question about the front bottom caliper slide pins (the ones with the rubber boot.) I track my car several times a year, and when I am putting on and taking off my track pads, the bottom slide pin is always super tough to get out. I end up taking a 15mm open end wrench to the inside with a 17mm box wrench on the bolt head turning back and forth to get it out. I use the purple ceramic grease from Orielly's. It's like the rubber has swollen and doesn't want to come out. When I grease it it slides in and out perfectly, but after the track day I'm back to the struggle.

Is there anything I am doing wrong? Any tips? I end up going through several pins a year because the rubber boot gets all messed up.

Heat :) All you can do is clean/replace them ...and grease and replace the boots as needed.

One of the reasons I went to a four piston front caliper that doesn't have rubber seals

Thanks Dan, just wanted to make sure it wasn't somdthing I was doing :)

Rotational Grinding Noise, left rear wheel
 

I've got an 04, MT. Changed the brake pads a month ago, and last week started getting a grinding noise from the left rear wheel.

The noise is in time with wheel rotation, becomes inaudible above 20-25 mph, and goes away when I brake.

I pulled the wheel and found no gap between the pads and rotor, and took a lot of force rotating the caliper off of the wheel. Pulled the caliper, removed the piston, which was in surprisingly good shape, lubed, reassembled, re-installed...twice...no change.

The piston is compressed into the caliper enough that the caliper slides easily back over the rotor.

I checked the parking brake adjustment nut under the center console, and loosened it, but no change.

I've seen reference to adjusting the parking brake at the caliper, but can't find a procedure to actually do it. Is there an adjustment other than the under console nut?

After my last attempt, I put the wheel back on, left the car up on jack-stands and listened/observed as my wife ran the engine in gear up to about 2k rpm. There is still a very faint grinding sound, but also an occasional "thunk" (not every rotation, maybe every 10 seconds or so).

I'm starting to think wheel bearing.

Any other things to check?

First thing thst came to mind is your caliper slide pins are siezed up. I would take them out, inspect and regrease them. My second thought is your rotor is some how not flush. I would take off the rotor and then make sure everything goes back together properly. Good luck.

Make sure you retract the pistons properly and that you align the pin and the groove properly. Once I had a problem with the parking brakemechanism binding from not retracting it completely...and it acted like the brake was dragging. I removed the pads and retracted the piston completely and it worked correctly after that

Does anyone know the brake master cylinder BORE size?

Thanks for all the info. My '8 needs new front pads. I only autocross occasionally and the '8s brakes are certainly not my limiting factor :) So I'll stick with OEM pads.

Thanks again!
Chris

^ The OEM pads are really very good. Mazda did a lot of things right with this car, and the brake system is one of those things.

I AutoX my car at least once a month year-round, drive it on weekends, occasionally drive it to work and back, and have now done 2 track days. The OEM brakes have performed very well for me at my level of skill. The track days did force a flush and fill afterwards, but that is to be expected. I only experienced a bit of fade at the end of each day (2nd to last lap both times). New fluid and re-bedding brought everything back in line with the OEM pads and rotors both times.

I have only pondered track pads this month since I have a track day at Eagle's Canyon next month, which features very long straights followed by 90 degree turns. I am going to incrementally upgrade to Hawk HP+ pads on stock rotors with Motul 600 this weekend in preparation for ECR next month.

This thread has been tremendously helpful to me, and I look forward to applying more and more if it as I progress as a driver. Thanks!

Glad to hear you're upgrading the fluid. Once you have gotten to the point of boiling fluid it is time to upgrade :)

Keep an eye on your HP+ pads and rotors while tracking. It was probably the particular track, but the track was too much for my HP+es. I absolutely loved them, but they started to leave material on my rotors (check page 7 of this thread.) Also keep an eye on the thickness they went quick. Good luck and have fun!

Well...

Eagles Canyon was fun. It really was. And, it taught me quite a bit about brakes--or at least how various components respond to heat.

I upgraded my brakes to Hawk HP Plus pads and ATE Type 200 DOT 4 fluid (could not find Motul 600 locally in my time frame). When I installed the pads, I used the OEM shims and applied a light film of the included brake grease between the shims and pads and shims and pistons like I normally do when replacing brake pads. The heat generated at EC was so intense, it turned the grease to carbon and burned nearly all the paint off the pads and shims.

The friction material on the pads held up (to my surprise), as did the rotors, although I fear that if I push it any harder next time, I may need higher temperature pads.

So, here I am waiting for my Mazda dealer's parts department to receive shim/clip and caliper rebuild kits so I can rebuild my brakes again.

A few obvious questions (yes, I have done lots of searching):

1. Do those of you who track your cars use shims?
2. Do you bother to use brake grease at the track? Which grease? Is the Permatex 3,000 degree stuff any good?
3. Should I be thinking about a BBK to help deal with the heat? Is there a known good one?

I know after my grease burned up, my brakes when from a high pitched singing sound to sounding like a train whistle and a fog horn had an alien love child.

For now, the plan is to rebuild the brakes with OEM parts and drive it that way around town and at autoX. I will put whatever track pads on a few days before track day, potentially with aftermarket shims (Centric or similar) and potentially with higher temp grease until I find a good formula.

Cheers!

Hello, I think it'll be beneficial to upgrade your pads to a full track pad. I remove the shims when I put on the track pads, especially the front shims, since the two materials start to seperate and I've needed to repurchase them. Also they will howl with or without the shims anyway. I don't use the grease with my track pads.

I had problems with the HP pads the last time I used them. I over heated them. There are pictures and a description on the previous page. Now I am using Hawk DTC60 pads and they are working good for me.

^ That may well be where I end up too.

I have ordered all new OEM shims/hardware for my OEM pads. That setup will permenantly pair with my OEM wheels and street tires.

My track wheels and tires will pair with the Hawk Pads I have until I wear them out or experience problems with them. The next track day I attend (might be the 31st at Motorsport Ranch), I will try the Hawk pads with generic Centric shims and 3,000 degree racing grease. I don't want to go completely without shims if I don't have to, because shims do serve the purposes of heat transfer and torsion control in addition to helping to quiet things down. If that setup doesn't work, I will keep removing variables until I am down to no shims and no grease.

I was hoping it would be realistic to run a dual purpose setup and not have to change pads before and after every track day, but that seems to have been a pipe dream.

Anyone have any Stoptechs? I heard they are great, bite good and don't melt your calipers like HP+. Also heard they are quiet, but any experience with them on the 8??

Here is an excellent post on brake fluid, which includes a chart that shows the verified specs of a few dozen different brake fluids.

https://www.lelandwest.com/brake-flu...ow=1&SF=4&ST=2

Brake Question
 

Just bought to sell a 2004 RX8... Brakes went to the floor.. what is the big unit all the lines go into? ABS? Need to sell it.. But, need brakes.. E Brake is good Hear a woosh from the big unit... without the engine running... any ideas?

Sounds like the brake booster.
You could get lucky and have a bad check valve, might want to look at that.

Where is the check valve?

The "whoosh" sound is coming from the unit that all the lines go into,,, down line from the master cyl and booster.. I am old school and not sure what that thing is... has a electrtic motor on it too..

The whooshing is not coming from the booster?
I'm not sure if that's the proportional valve or ABS.
Only whooshing sound I've heard is from the check valve in the booster, or the booster itself.
Usually the pedal is hard if it's the valve, and goes to the floor if it's the booster.
I'll take a look at mine later to see what you're talking about.

One little thing I want to mention about the original post: it is actually possible to switch between a glycol-based and silicone-based fluid. You should never mix them, however, so flushing thoroughly (3-4 times) with an appropriate solvent is necessary before bleeding in the new fluid. I've used denatured alcohol in the past with good results, it won't affect the seals as long as they aren't rubber (modern brake systems use a nylon-based material).

Heavy vibration during braking at 50mph and below
 

Looking for a little insight on what to do. Brought my 2008 Rx-8 to the local dealership to get my tranny replaced as well as my brakes and rotors. They said nothing about my brakes or rotors, so i thought Id ask everyone else sincethey are of no help and you guys/gals are awesome. Thanks!





2008 Rx8 40th editio

What kind of insight?
They are not hard to do if you have any mechanical aptitude, and you can save a lot of $$.

Does anyone have the Mazda part numbers for the front rotors, caliper, master cylinder, and rear proportioning valve from the base AT model? I am considering the feasibility of converting to the smaller brakes due to the difficulty in finding gravel tires in 18" wheel sizes.

^ Not intending to be a jerk, but why would anyone have that?

All of your questions are answered here:

https://parts.com/

Jim Ellis Mazda Parts' website is your friend...
http://www.jimellismazdaparts.com/default.aspx

2005 Mazda RX-8 FRONT BRAKE MECHANISMS

2005 Mazda RX-8 REAR BRAKE MECHANISMS

2005 Mazda RX-8 BRAKE MASTER CYLINDER & POWER BRAKE

How about in 17"? Many 17" rims will fit over the sport brakes.

SCCARallycross

Gravel tires are mostly in 15" sizes and below, with a few vendors offering them in 16" sizes (though the selection drops off a cliff). I am also attempting to find out if there are any 15" wheels that can accommodate the base AT brakes; but, if no such wheels exist, then I will have to settle for 16" wheels and the meager choices of gravel tires that will go on them. I am getting my 2004 set up for it and will already be in the PR (prepared, rear wheel drive) class, as I had already switched to long stroke coil-overs from FlatoutSuspension, so I could stop grinding my car in the rear on the speed bumps in the condo where I live (crossing at extreme angles doesn't work as the worst ones are at narrow choke points in the driveway).

FYI, I do not think you were being a jerk. It was an entirely reasonable question.