Any reason NOT to buy Racing Brake 2pc front rotors?
 

Other than cost, obviously.

Brakes will be otherwise stock, including pads. 100% street use for now.

Thoughts?

Overkill? ;)

Sounds good to me! lol

I mostly want them for (the promise of):

1. Mass reduction
2. Less heat transfer to the wheel hubs
3. Better-than-OE durability

In that order.

I'm a hard parker with a BBK and two piece rotors front and rear :) I tell you what though, every time I brake hard in my 335i I really appreciate the brakes on my RX-8.

I'm site you miss a few other things too. ....likely everything but the torque 😊

Willwoods are cheaper and just as good with potentially more spare parts availability and more pad options?

Only looking at rotors, not a full BBK.

In that case, the only reason I can think of, is their rotor material is incompatible with some pad compounds like those from Carbotech.

Yeah, I read that. Hoping it's not an issue with stock pads.

Fixed ;)

I actually think they're kind of weird looking. :-P

for street use...

#1: sure, but is the weight reduction worth the cost for 100% street use?
#2: shouldn't matter for 100% street use - even for track use, I haven't really heard of many, if any having issues
#3: OE durability hasn't been an issue with anyone IIRC

It sounds like you're looking for justification to spend $$$ on it. If you like it, go for it - you don't need to justify it to anyone but yourself!

Well yeah, no one thing would make it worthwhile on its own. It's the package that's interesting to me.

As for OE durability, I'm on the original rotors at almost 57k; they have plenty of thickness left but they're scored and uneven, and I'm told they won't likely take well to being resurfaced. Last time this happened to me regularly (previous car), switching to slotted rotors fixed it. :dunno:

Yeah it's definitely a lot less tossable and just not as fun in most ways compared to the 8 but man it is nice to have a car respond to mods, it makes spending the money so much easier. And for long drives it is a blast. Honestly it's probably faster now than my RX-8 too, just a different kind of fast.

OEM rotors machine just fine. I had mine turned when I gave up on Hawk pads and switched to Carbotech. They have seen about 20K track miles and are still going strong. They are very high quality compared to a lot of aftermarket rotors and last a long time. I can use pretty much any brake parts I want, and I stick with OEM, because there is no reason to change IMO.

AFAIK the problem wasn't the rotors themselves, but the wear pattern. :dunno:

Heard this from the Mazda dealership when I took my car in for an inspection. I've been there a few times and, if this was a bad piece of advice, it'd be the first. They seem to have been super conservative with their advice, and they've been pretty on-point with the few things they've warned me about.

Happy to donate my rotors to someone local so they can resurface them and see what happens!

I have not inspected your rotors, so I can't know how they look. But, I would be very surprised if they are beyond being usable being so young. I spend a lot of time at the track, and most of the RX-8 and MX-5 guys I know are running either OEM rotors (original or new purchased from Mazdaspeed Motorsports) or Wilwood BBKs. Outside of the BBKs, we have all tried a lot of other aftermarket parts (StopTech and the like) and have found OEM rotors to be superior. Many of those guys started with OEM rotors having more than 100K miles on them before hitting the track, and they are still going strong after adding many thousands of track miles.

In the end, it is your car. Do what makes you happy. If you opt for the RB rotors, be sure to let me know how they work out.

I don't have a particular opinion on the two-piece (I've eyed them myself at Goodwin Racing), but I can say I'm extremely impressed with the OEM brakes. My RX-8 is just over 7 years old and has 52,000 miles on it. It's had one track day (hopefully another this year), and lots of back road driving, and the brakes are still in great shape with lots of life. I love the way they feel and perform, including at the track day I did last Memorial Day weekend.

I'm wondering if the two-piece RB rotors from Goodwin are actually cheaper than OEM, at least at dealer prices. I had StopTech premium high-carbon rotors and their pads installed front and back on my 2014 Mazda3 for $150 less than what the dealer wanted to charge me for just the Mazda OEM rear brakes and pads, and the car stops better, with better pedal feel, than it ever did before.

My local dealership quoted me for pads and rotors; the quote for parts and labor was like two-thirds the price of the RB 2-piece rotors alone.

Lol, you said dealership.

Yeah, that was my point. Even a theoretically expensive dealership estimate for parts and labor on pads and rotors is still only two-thirds the price of RB 2-pc rotors alone!

You are beyond justification and rationalization and into reaching and grasping. :eyetwitch

Just do what I do. Grit your teeth and make the hard-to-justify purchase. Then spend a little while wallowing in buyer's remorse. Then get over it and enjoy your new parts. :hahano:

...Wait, what?

I was responding to Chibana's post, in which he said this:
All I was doing was illustrating that the opposite is true -- RB 2pc rotors are WAY more expensive than OE, even at dealer prices.

Oh. Sorry. In that case, allow me face palm myself.

:uh:

No worries!

FWIW, I did end up springing for the 2-piece rotors, so I guess I took your advice in that last post anyway! :lol: If I do end up wallowing in buyer's remorse, I'll come back and post about it so you can say you told me so. :beerchug:

haha - what's the remaining thickness of the stock rotors? unloading them by chance? I'm still on my stockers after a bunch of track days and 55k+ miles... they seem to be lasting pretty well :)

Not sure what the remaining thickness is. But yes, definitely unloading them -- preferably to someone who'll resurface them and... evaluate the advice I got. :]

RB rotors are on!

Man oh man, does that hardware-to-bracket clearance make me nervous. There's like 1mm! :sweatdrop

No signs of trouble yet. As promised, I'll post back if there's reason to eat my words.

I'll also try to measure the stockers to see how much is left in them.

^ You can't make a post like that without including pics. This is clearly a violation of the rulez!!!

Didn't snap any during the install unfortunately, so this is as good as I can offer. Witness the awesome power of my dirty and slightly curb-rashed wheel!

https://cimg6.ibsrv.net/gimg/www.rx8...7e2dc95871.jpg

Also, there seems to be more hardware-to-bracket clearance now that the wheels are on, for what that's worth. I'm guessing the rotors just hadn't been fully seated before.

Looks great. Too bad they don't play nice with Carbotech pads.

FWIW, RacingBrake support told me this was an issue with some ceramic pad compounds. They say the alloy they use for the friction ring is too hard to allow those ceramic compounds to bed in properly. Apparently semi-metallic compounds don't have that problem. No idea how to evaluate that claim, but there it is. If it's true, then Carbotech's semi-metallic compounds should be fine. Thoughts?

You know, that is something needs to be verified. I think I remember someone from Carbotech telling me that a year or so ago, and I think I remember reading where Racing Brake has said the same thing, but I should be sure of it before spreading rumors. I'll call both today and see what they have to say about each other.

Hey, Steve...
Not quite there yet, but...

Not sure if you ever got around to this, but I just had pretty much this exact convo with Carbotech. Their version of the "incompatibility" story is that RacingBrake used to have significant quality issues, which was the real culprit in the incident that touched off the whole RacingBrake/Carbotech incompatibility thing. He also dropped a few other tidbits that make the story more detailed and coherent than what I had been getting from RacingBrake alone.

Here's the story as I understand it: Basically, RacingBrake's rotors accumulate pad material more than others do. This probably has something to do with the harder alloy just refusing to go anywhere. Either way, if you're using a relatively abrasive pad (poor rotor wear), there's less need to worry about pad deposits because the pad's abrasion keeps the deposits in check. But if you're using a pad that's really mild on rotors, and you get it really hot, deposits will accumulate. That's probably where the "no ceramic" thing comes in; ceramic pads tend to have less rotor wear and lower heat ranges, so they're more likely to heat up enough to leave deposits without being abrasive enough to keep those deposits in check.

Per Carbotech, their pads tend to be nicer to rotors than, say, equivalent Hawk pads. Meanwhile, RacingBrake highly recommends Hawk pads...

I can attest to the fact that Carbotech pads can leave deposits--especially in high heat environments. I use their XP10 and XP8 pads as track pads on both my Miata and RX-8. They do occasionally gum up rotors with uneven deposits in the summer. The remedy is to cool them down completely, then bed them in again from cold. The cold pads scrape the old deposits off, then lay down a new friction layer as they heat up. Cool everything back down, and you are good.

It is a perfectly reasonable explanation that RB's rotors may be or have been more susceptible to accumulating deposits from such a pad, and that more abrasive pads are less prone to do it (at a cost of higher rotor wear). I'm sure it depends on the metallurgy and quality control.

It is also reasonable to wonder if RB likes Hawk pads, because Hawk pads result in more replacement rotor ring sales.

Fixed that for you

The people here on this forum using them with highly aggressive pads report much better wear. Plus they don't crack or warp. FWIW I remember when Carbotech "used to have some manufacturing issues". The BS rationalization games people get into are really tiresome.

I don't see this as being any different than someone posting a thread about putting a hipo/race seat in their otherwise stock street car and initially being fussy about the installation/fitment then later complaining it's a pain to get in/out of, not comfortable because it's too restrictive, etc. followed by claims the manufacturer is obviously overrated and so on.

All I know is, I use Carbotech pads on whatever rotors are cheapest on Rock Auto, and pads and rotors last a very long time. All the Hawk pads I tried ate rotors like crazy. It would never occur to me to run Hawk pads on expensive rotors simply because of that fact. Maybe RB rotors are awesome enough to withstand the Hawk abuse, but I'll not be betting my money on it. My approach works great, and I see no reason to change it.

Isnt it relative to the Hawk pad youre using? HP plus tore through rotors on my cobra very quickly. Switched to HPS and have had a significant decrease in premature wear, with somewhat comparable performance (granted I'm not a very good driver).

Side note, did you ever check temp difference between pads?

True, and the OP is talking about street pads. I'm mostly interested in track pads, so I'll bow out now.

The impression I get is:

- If you were already going to use a Hawk pad or any other high-rotor-wear pad for whatever reason, you'll be much better off with a RacingBrake rotor because it'll hold up much better.

- If you pick a pad material that can have pad transfer issues in any situation, you might be worse off with a RacingBrake rotor. The pad transfer issues will be more likely to happen and worse when they do happen.

- If your pad material is somewhere in the middle, a RacingBrake rotor should still last longer than most other options, though whether it's worthwhile is up to you.

Missed this post earlier. It's a fair point, and I do appreciate what you've said on this and related topics, so I thought I should respond.

I completely agree that the purported mechanism here -- rotors being too hard for mild pads to keep clean -- makes logical sense in a performance context. But this isn't a case of stumbling blindly into a well-known peculiarity of a whole class of performance parts.

Two things are different here:

1. This particular quirk seems to be unique to RacingBrake, or close enough. No other automotive iron rotors seem to be widely known to have it, including track-oriented rotors from known performance brands. I've spoken with a lot of trackday enthusiasts and brake part vendors about this, including Porterfield, StopTech, Good-Win-Racing, etc.; the only ones who had even heard of such a thing were employees and customers of RacingBrake and Carbotech talking about RacingBrake rotors.

2. Having read about this potential issue, I called RacingBrake before placing my order and asked them specifically about using OE pads with their rotors. They gave me multiple direct and explicit assurances that OE pads would be fine. Only very recently did they change their tune, having exhausted all other explanations for my chronic NVH issue besides rotor quality defects.