# Quetsions regarding upgrading to two piece rotors



## MrRline (Apr 6, 2010)

Ok so i've seen these rotors talked about in a previous thread([please see picture below), but i'm really new to the idea of a two piece rotor. I was hoping others on here might be able to give me some more information as well as answer a few questions. First off cars a 2010 CC R-line if that makes a difference in your decisions. Also before anybody chimes in that the two best upgrades you can do for braking are a good set of tires and brake pads, I have already pretty much settled on the idea of using the ebc red stuff pads and i'm pretty happy with my conti's right now, but i'll be moving to a better performance tire about the time I use do this upgrade. Also because I know it will come up I don't track the car, but occasionally will be taking it to the strip and I drive pretty aggressive often so I want something that will suit my needs for the time being. 

These are the rotors in question. They are a two piece design according to the site and made by racingbrakes. I was told this is a brand a lot of scca vw's use. My main question is what is the advantage of a two piece rotor over a one piece rotor system? The only real thing I can see so far is that compared to stock this rotor is about 5 lbs lighter is there other things about using a two piece that are beneficial? Are there any disadvantages? Am I better off looking into a big brake upgrade?










My next question was if I were to go with something along these lines what's the recommendation should I just go slotted or drilled or slotted and drilled? I have been told that often times when drilling the rotor it can become weak and crack? Can this happen often with any set of rotors or only on inferior quality? I already know that slotted helps to remove gas through the slotted channels and drilled I have been told really doesn't do much. I do like the look of drilled and I see it on a lot of cars recently such as vettes and porsche's and such, but i've never owned anything that was slotted or drilled so i'm looking for input.


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## greyhare (Dec 24, 2003)

A two piece rotor of the same size will be lighter. Two piece rotors isolate the wheel hub and bearings from brake heat better. Metal expands when it heats up; brake rotors do not reach the same temperature across all areas of the rotor. As a result of the uneven heat distribution some parts of the rotor expand more than others, causing coning. (The rotor disc becomes cone or bowl shaped.) A fixed mount two piece rotor reduces the coning by allowing more flex at the rotor hat; a floating mount two piece rotor eliminates coning by allowing the disc to expand independent of the hat.

As for rotor face...

Plain is preferred for street use, plain or slotted for track use. A good quality drilled rotor should not crack under street use but very likely will under track use.


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## GTijoejoe (Oct 6, 2001)

greyhare said:


> A two piece rotor of the same size will be lighter. Two piece rotors isolate the wheel hub and bearings from brake heat better. Metal expands when it heats up; brake rotors do not reach the same temperature across all areas of the rotor. As a result of the uneven heat distribution some parts of the rotor expand more than others, causing coning. (The rotor disc becomes cone or bowl shaped.) A fixed mount two piece rotor reduces the coning by allowing more flex at the rotor hat; a floating mount two piece rotor eliminates coning by allowing the disc to expand independent of the hat.
> 
> As for rotor face...
> 
> Plain is preferred for street use, plain or slotted for track use. A good quality drilled rotor should not crack under street use but very likely will under track use.


basically right on the money :thumbup:


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## MrRline (Apr 6, 2010)

greyhare said:


> A two piece rotor of the same size will be lighter. Two piece rotors isolate the wheel hub and bearings from brake heat better. Metal expands when it heats up; brake rotors do not reach the same temperature across all areas of the rotor. As a result of the uneven heat distribution some parts of the rotor expand more than others, causing coning. (The rotor disc becomes cone or bowl shaped.) A fixed mount two piece rotor reduces the coning by allowing more flex at the rotor hat; a floating mount two piece rotor eliminates coning by allowing the disc to expand independent of the hat.
> 
> As for rotor face...
> 
> Plain is preferred for street use, plain or slotted for track use. A good quality drilled rotor should not crack under street use but very likely will under track use.


Gotcha on the coning part very informative. With a two piece set is there any significant chance that the two pieces would separate under very hard or continuous braking or should I be safe?

As far as the slotting goes I think i'll pickup a set of slotted just because I like the look of it and if I do decide to hit up a track anytime I have something nice and if not then I have something that will provide ample performance on the highways.

One last question too. Would I be better off picking up a set of something such as adams rotors or would the two piece be a better bet. Only reason for asking is by the time I do front and back i'm looking around 900 bucks and that's the price of a big brake upgrade from 315mm to 345mm(cc stock to cc vr6/R32 brakes)


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## GTijoejoe (Oct 6, 2001)

dj_cronic_metal said:


> Gotcha on the coning part very informative. With a two piece set is there any significant chance that the two pieces would separate under very hard or continuous braking or should I be safe?
> 
> As far as the slotting goes I think i'll pickup a set of slotted just because I like the look of it and if I do decide to hit up a track anytime I have something nice and if not then I have something that will provide ample performance on the highways.
> 
> One last question too. Would I be better off picking up a set of something such as adams rotors or would the two piece be a better bet. Only reason for asking is by the time I do front and back i'm looking around 900 bucks and that's the price of a big brake upgrade from 315mm to 345mm(cc stock to cc vr6/R32 brakes)


First I should state, that the disk shown looks like a POS in my opinion... looks like cast hat and ring, probably the cheapest method to make a floating disk. (thats neither here or there).
A well designed pin and bobbin design will take all the brake load just as good as a goose neck disk design, they both have to endure torque strength testing so it shouldn't be a concern. If money was no object, every car in the world that has brake disks would have floating.

Secondly, if you are worried about $$$ just replace the fronts with 2-piece and the rear will conventional goose necks.


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## MrRline (Apr 6, 2010)

GTijoejoe said:


> First I should state, that the disk shown looks like a POS in my opinion... looks like cast hat and ring, probably the cheapest method to make a floating disk. (thats neither here or there).
> A well designed pin and bobbin design will take all the brake load just as good as a goose neck disk design, they both have to endure torque strength testing so it shouldn't be a concern. If money was no object, every car in the world that has brake disks would have floating.
> 
> Secondly, if you are worried about $$$ just replace the fronts with 2-piece and the rear will conventional goose necks.


Below is the link of what was posted on the CC forums a few months back. I hence where I got some of my information from. Would you be able to tell me if it's the method that you were saying from the information on their website or no? 

As far as the money goes I don't mind spending the money, but i'm looking somewhat for the best bang for my buck upgrade to rotors. Eventually I want to go big brake I'm just trying to decide if that should be on the next set or if I should try a two piece first or go with the adams rotors.

adams rotors front 250
racing brakes 2 piece frotn 450
BBK upgrade 315mm to 345 R32/Vr6 4mo 900-1200

http://forums.vwvortex.com/showthre...C-GTi-312x25-Two-Piece-Rotors&highlight=rotor


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## BsickPassat (May 10, 2010)

there really isn't a performance advantage to adam's rotors on the street. It's all about paying extra money for aesthetics. He used blanks from "OEM" or Centric in the past... he doesn't really say where he gets rotors from. Plus, does he rebalance the rotors after he does his drilling/milling?

If you're after a slotted rotor... try ATE Premium One, or (Centric) Power Slot rotors.

2-piece rotors... try looking up how much those replacement rotor rings cost. Not cheap.

in the end... your biggest bang for rotors is.... the stock rotors.


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## MrRline (Apr 6, 2010)

BsickPassat said:


> there really isn't a performance advantage to adam's rotors on the street. It's all about paying extra money for aesthetics. He used blanks from "OEM" or Centric in the past... he doesn't really say where he gets rotors from. Plus, does he rebalance the rotors after he does his drilling/milling?
> 
> If you're after a slotted rotor... try ATE Premium One, or (Centric) Power Slot rotors.
> 
> ...


ATE doesn't show that they have a rotor available for the CC from what I can see. Centric does have a regular one piece blank. As far as the cost of 2 piece again I said i'm not worried about the cost, but wanted to know performance wise if it would be worth it vs paying a couple hundred bucks for a bbk. At this point im either going with the racingbrakes or the adamas rotors. I want something more asthetic, but also something functional.


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## BsickPassat (May 10, 2010)

dj_cronic_metal said:


> ATE doesn't show that they have a rotor available for the CC from what I can see. Centric does have a regular one piece blank. As far as the cost of 2 piece again I said i'm not worried about the cost, but wanted to know performance wise if it would be worth it vs paying a couple hundred bucks for a bbk. At this point im either going with the racingbrakes or the adamas rotors. I want something more asthetic, but also something functional.


the CC is a Passat. And yes, they are available for your 2.0T. I know this because I have them on my Passat


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## GTijoejoe (Oct 6, 2001)

Ok, not as bad as I thought, at least its an Al hat... pin/bobbin design still looks like crap.... you know how a quality pin/bobbin setup looks like? Look at PFC racing.... those are real 'racing brakes' :laugh:

For the price, they're not that bad for the weight savings.


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## ROH ECHT (Dec 9, 2010)

If cost isn't an issue, then get a bbk. The oem brakes are derp! Not even worth putting a 2-piece together with those. Aesthetics is all you will get out of the oem calipers. You can put braided lines, redstuff pads, and drilled and or slotted rotors on and you have wasted that cash(IMO). Put it towards a performance set-up if performance is what you're after. 
Mine are drilled and slotted and work great. The drilled are lighter. Less power needed to get rolling, and less force to stop rolling.


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## adam's rotors (Sep 20, 2006)

from factory replacement rotors to BBK, we're the spot to *stop*...
check us our online or shoot me an email.


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## GodSquadMandrake (Feb 17, 2004)

dj_cronic_metal said:


> ATE doesn't show that they have a rotor available for the CC from what I can see. Centric does have a regular one piece blank. As far as the cost of 2 piece again I said i'm not worried about the cost, but wanted to know performance wise if it would be worth it vs paying a couple hundred bucks for a bbk. At this point im either going with the racingbrakes or the adamas rotors. I want something more asthetic, but also something functional.


 Racing Brake is the best hands down for racing in my opinion because: 

1) Convergent, curved cooling vanes. - patented design. Increases cooling and features right and left fitments. Many other manufacturers are using curved vane rotors that are the same left and right so on the opposite side they are not facing the right direction. The convergent vanes are helpful because they cool the outside edge more. The outside edge is spinning faster and gets hotter. You can see this effect on an old rotor where the outside is darker. 

2) Offset mounting tabs. The mounting tabs are mounted inboard and outboard of the rotor ring. This allows the brake torque to be evenly distributed. In any other two piece design the rotor is mounted only on one side. 

3) Center mount. The rotor ring mounts in the center and allows better airflow the center. Brake rotors are center breathers. 

4) Open slot design. Strong and doesn't clog. 

etc etc.


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## GTijoejoe (Oct 6, 2001)

GodSquadMandrake said:


> Racing Brake is the best hands down for racing in my opinion because:


  
You should find out, does racing brake supply parts to any professional A class racing program? 
That should tell you who's who about 'racing' :thumbup: 
This field of technology is where the heavy hitters lie, its the most serious of conditions to test your ultimate designs and capability as a racing brake supply company.


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## GodSquadMandrake (Feb 17, 2004)

GTijoejoe said:


> You should find out, does racing brake supply parts to any professional A class racing program?
> That should tell you who's who about 'racing' :thumbup:
> This field of technology is where the heavy hitters lie, its the most serious of conditions to test your ultimate designs and capability as a racing brake supply company.


 Hmm I'm not sure. Are you saying you know of someone better? Maybe carbon brakes? They might cost a lot more though. 

Don't take my word on anything though. I'm not a sales rep. Here's the best review I know for Racing Brake though and plenty of info: 
http://www.rx7club.com/showthread.php?t=605463


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## greyhare (Dec 24, 2003)

I don't really know anything about Racing Brake Supply so I will not say better... 

They do supply brakes for many series.


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## GTijoejoe (Oct 6, 2001)

GodSquadMandrake said:


> Hmm I'm not sure. Are you saying you know of someone better? Maybe carbon brakes? They might cost a lot more though.
> 
> Don't take my word on anything though. I'm not a sales rep. Here's the best review I know for Racing Brake though and plenty of info:
> http://www.rx7club.com/showthread.php?t=605463


 I should start of by saying its not my intentions to through 'racingbrakes' under the bus and call them crap. I have no experience with any of there products but I am also not ignorant enough (not saying you are) to believe any product that comes on the market is awesome because they say it is. 

For instance, everything posted in that article is good general brake design information which probably isn't known by the average joe, so when average joe learns about this info he maybe impressed. For example, anyone who makes curved vained disks and doesn't make them RH or LH side excluse is an idot, its the entire purpose of direction vained disks... its very elementary knowledge. In addition, don't be naive about patents, I'm not stating racing brakes patents are crap, but honestly, everything that gets patented doesn't mean its good, it only means someone else hasen't done it the eact same manor. There are many many rediculous patents out there for technical things that have no value, or still isn't as good as another design. 

I'm just stating that real racing brakes go on real racing cars in real racing sanctions. Carbon disks or carbon ceramics are commonly known as brakes that race cars use, but that doesn't mean they are the only real racing disks made. There are multiple sanctions that do not allow the use of carbon for competitiveness of budget (if you have more money you can make a better car).... so that being said I would say racing brakes like those known companies, Brembo, APracing, PFC... perhaps even Alcon.... these companies make serious racing brakes for F1, Indy, cupcar, lemans.... etc the list goes on of course 

I'm just trying to open your perspective and look at things in an educated manor before you're sucked in to claimed awesomeness. I personally have a brake design background, I work with peolpe who have designed real racing brakes that are currently being used by F1, Indy etc....I have read, issued, and exaimed all kinds of patents of my own, so I speak from an experience of information :thumbup: 

All that said, I really hope racingbrake as a company does make good products and in the future we'll all learn that to be true, especially because the price is very competitive to other choices on the marketeace:


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## ITB45 (Feb 27, 2008)

First you never stated your problem. Are you getting brake fade? Pedal suddenly gets soft? 

Break fade would, mean you need better pads, or a larger rotor. Sudden soft pedal would mean you need better brake fluid. 


I wouldn't waste the money on two piece rotors. They are more bling than bang on a street car. 

Second I would trash those EBC pads, all the EBC pads are garbage in my opinion. If you are burning pads that bad on the street, get something like HAWK Hp+ 

I don't know anything about your break application, but can you swap bigger rotors from an Audi or another car?


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## GodSquadMandrake (Feb 17, 2004)

GTijoejoe said:


> I'm just trying to open your perspective and look at things in an educated manor before you're sucked in to claimed awesomeness.


 Are you talking to me?


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## GTijoejoe (Oct 6, 2001)

GodSquadMandrake said:


> Are you talking to me?


 not specifically.... :beer:


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## GodSquadMandrake (Feb 17, 2004)

Ok I wasn't sure because I'm not the one buying them.


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