Brake Rotors - Which ones are track-worthy
 

Started up on some research on sprort brakes.

Brembo - Can't find a replacement
Akebono - Can't find this one either but it must exist since it's the stock one right?
StopTech (Cryo-Sportstop) - Drilled and/or Slotted
BPI - Drilled and/or Slotted
Centric (125)
Diskitalia - Drilled or Slotted
Xbrakes (4000 series) - Slotted and/or Drilled
DBA - Slotted and/or Drilled
EBC - (Ultimax) Slotted

My main question is who has experience with any of these and whether you've had any problems you would attribute to them.

Also, if there are any XP8 pad users out there, which ones do you use and have you had noise outside of the less than 5mph area?

Unless you are racing for money and top times, get the cheapest quality brand and cryo treat them. That's all you need.

I am the "Brake Whore" of the VW world and i will tell you the following...

If you want to do Track Duty on rotors... you must have a 2 piece rotor.
- Everything else is a gimic, IMHO.

Drilling makes them worse (cracking prone, look at any Corvette)
Slotting is good but eats up pads faster
2-Piece cost about $500 but worth every penny to save your arse.
Cryo Rotors sounds nice but ehh, i wouldn't bother, it's cheaper to just buy a couple sets of OEM's.

You will not gain any braking power or longevity with any of the above solutions unless you get a 2 piece rotor. I have seen those available here, but nowhere else yet.

Additionally if you want brake longevity consider the stillen brake cooling kit, $275 which will extend pad and rotor life.

FINALLY... Don't drive XP8 on the street they'll squeal like stuck pigs. Just swap out your pads for the track day. This also keeps you mindful of your pad level on both sets of pads.

Then again this is just my opinion... i could be wrong.
~ The Brake Whore
:tiphat:

You guys make a lot of sense.

I'm really liking the look of that Stillen brake duct kit too!

Yes buy the ducts, they would make your pads last longer. Two piece are great. If you can justify spending that much $$, more power to you. Cryo treatment works great. I used to have cracking issues with my cross-drilled Corvette rotors, problems were solved after I starting cryoing treating my rotors. Rotor is a heat sink, it just have to hold the heat and dissipate them....

I have over 12 track days on my car on 4 different set of pads, barely any wear on my rotor....

I bet you're not using Hawk pads. ;)

Been down that road, never using it again. Last two times I used it I killed the rotors both times (HP+ and HP Blues). My stock Prius brakes have a better feel than the crappy HPS.

:iagree: And HP+ pads suuuuuuccckk. Love my XP 8's. Have some XP 10's next. Only because I got a steal on them.

If you do go 2 piece, look at Racing Brake. Open slot design too. I cannot give feedback on them yet as they are just getting installed next week!

I just installed a Racing Brake BBK and it looks amazing... dare i say... comparable to my beloved stoptech kit?? !!

But yes, racing brake is a solid brand with good customer service and amazing products. Their 2-piece OEM replacement rotors MSRP of $920 is $100 less than the only other available replacement from DBA which are available from Stillen.

Thoughts comments ?
:tup:

P.S. And for the love of all that is holy, do NOT get drilled rotors.

Example:

http://www.devtools.org/rus/mtimages/rotor-cracks-2.jpg

Yes drilled rotors were made for a problem in race cars which no longer exists. Look at the F1 cars brakes now days and there are no drilled holes or slots. Old pads made a lot of gases from the glue that held them together and these needed to be vented out in order for the breaks to preform. Drilled was the most effective but had the side effect of producing cracks so after each race they would need to be inspected and/or replaced. That's not reasonable for day to day use. Slots didn't crack and were better then nothing at all.

But today modern pads do not have much if any issue with gases being formed. F1 cars and other race cars don't use anything because it is not needed and holes or slots reduce the overall braking surface.

My advice is get the best 2 piece brake and good pads. Slots and holes are just for appearance.

http://bikehugger.com/carbon%20rotor.jpg
http://bikehugger.com/post/view/formula-one-for-bikes

What's the advantage of 2 piece?

lots of good information on this thread, keep it coming :tup:

Lighter weight, and you can change the rotor without changing the hat. It will cost less in the long run. But a little more $$ upfront.

Advantage of 2-piece rotors is that all the radial expansion that is in the rotor as it cycles from 200DegC to 700DegC and back again many times per track day lap is just that - expansion in a single plane.

When you have a 1-piece rotor, you get differential expansion in the centre of the rotor (the integral "hat" - the hump bit that fits over the hub) and the friction surface which causes stress and eventually the rotor friction surface will crack if the stress gets high enough.

I am a long-term DBA 5000-series user (because they are manufactured in Queensland - well, they were, but now in China but thats almost universal now) - I started in my first WRX Rallye Special in 1996 - and I have never had a rotor failure with them. I now get the rotors cryo-treated as they last longer.

I am also a long-term Endless pad user (TR compound originally, but now have a new one to evaluate), and occasionally use a Ferodo DS2500 for road and track (noisy and a fair bit of dust but good stopping and good temperature tolerance).

I always use a 2-piece front rotor given the extreme level of heat-stress going into them on the track.

Again - my preference has been for slotted rotors simply because they "wipe" the pad and clean any deposits that might build up on the pad surface. Remember - the pad is a sacrificial element in the system - it is designed to generate friction as the rotor abrades it away - so these bits (the "dust") need to go somewhere, and in my opinion, the slot helps "wipe" it away and this promotes braking consistency.

This thread states that F1 don;t use slotted rotors, and that is because F1 brakes are carbon/carbon and the mechanics and chemistry (there is a lot of both in a carbon/carbon braking system) are very different to an iron rotor-based braking system, so IMHO it is not really relevant.

So, to answer your question - I;d always go for a 2-piece rotor to avoid the potential for differnet rates of expansion between the hub and friction surface parts of a single-piece rotor which can only result in friction surface cracks (really big ones).

As for which one - that is up to you - you are in CONUS so you have a much wider choice than us down-under ... for my preference - I use DBA 5000-series, but my guess is that you'll have a much wider choice - so be guided by feedback from users on the forum.

As or cryo-treatment .... I do it as I've got 10+ years of emprical evidence out of my race car that it promotes rotor life - I get 1000klms+ out of my race car per set of rotors but then again - if you are only an occasional track-day user, maybe you're not so concerned at rotor life.

RB

Not sure that is necessarily true. With most 2-piece rotors you have to replace all the mounting hardware at the same time so you end up paying about the same long term. The AP rings alone cost me more than a set of solid StopTechs but they will last 12+ track days instead of 6.

The big advantage is that they can take a lot more track abuse due to the ring being able to freely expand separate of the hat. This is mainly important up front, the rears don't take as much heat (my front's get to 1100F, the rears only 750-850).

I also prefer the sweeping action of the slotted rotors. I have significant wear on my rotors yet there isn't a single gouge or irregularity on the surface, they are as flat as flat can be.

New rings and caliper seals are on the way from Stillen (thanks guys!) and I'll be all fresh for the season. I'm also switching the rear iron hats out for aluminum since I don't use the e-brake much anyway and it will save almost 20lbs of rotating mass.

So I think the bottom line is, if you track a lot then 2 piece rotors are worth the investment. If you track occasionally just get a solid or slotted rotor and get them cryo-treated.

Wow, great info.

For track use slots do provide a useful function, so do drilled rotors (but the cost out weight the benefits imo). I just won't use slots for a daily driver since they will eat through pads much quicker and have little function in daily use, the OP didn't mention track use so I assumed that wasn't a factor.

The carbon disks in F1 still do the same thing turning kinetic into thermal energy through friction which produces dust. Carbon is used because its much much lighter then steel and has much better thermal properties. But that's a discussion better left for another thread.

Um, isn't the title of this thread "Brake Rotors - Which ones are track-worthy"? :)

2-piece rotors allow for expansion and contraction of the iron ring (braking surface) without actually stressing the entire rotor. The hat is separate from the rotor-ring and bolted together with elongated holes to allow for the thermal expansion.

Sorry was already covered earlier... missed that big a$$ post above.

Although that being said, i warped the crap out of my Stoptech 2-piece rotors and had serious pad taper issues. I believe that was me just trying not to replace what amounted to another $500 for front rotors *cough.

I'm blind apparently

Dangit... Now I want the 2 piece for the front. Great info guys!:tup:

Anyone have any specifics on the cyro-treatment process like what temperature and how long? I work on heat treat furnaces and a number of the customers I deal with have cryo-processing capabilities. Just trying to figure out if I might have a way of getting cheap/free cryo-treating

Sounds like poor pad compound choice. I had the same problem in 2010 when I tried to use DS2500's in this car, left horrible pad deposits causing the "warp" effect and they tapered badly within 2 sessions. Things just got too hot for them to handle. The good news is I was able to restore the rotors and remove the deposits.

Also bleed the brakes carefully, if you develop a gas bubble on one side of the caliper you will get uneven pad pressure and horrible shudder.

two-pieces with the right hardware also help to prevent heat from transferring from the rotor to the hat to the hub to everything...

and as far as a pad 'sucking'.. its pad choice... the more aggressive the race pad, the more it will eat rotor if they are not up to their correct operating temp.. this goes to the 'squealing' on the street too.

and if youre not seriously racing there is a 'cost to longevity' factor... if one piece rotors are $200 and you get 5 track days out of them, it beats the $500 rings that make it 10 track days.

Reviving a dead thread to thank everyone for a wealth of knowledge. I'm seriously happy my G is so close to the Z as far as parts. The G community is not nearly as helpful or organized (IMO).

Anyone have experience with CZP 2-peice rotors?

Also, when will we have a 2-peice rear option available?

I believe Racing Brake makes rear two piece rotors? I remember a group buy for them a long time ago.

I believe that for the akebono's the only rear 2 piece rotors available are the Relentless Autosports rotors... I could be wrong though.

Lot's of useful info on this thread, but it feels like some of the info isn't 100% accurate. It's a bit hard to believe drilled rotors are as bad as some people make them out to be considering it's still widely used in a lot of high end sports cars. I've seen drilled rotors crack, but I've also seen solid rotors crack. I think it really has a lot do with the manufacturer, conditions and usage. For track worthyness, it really depends on how much track use you're actually doing. What's best for the track isn't necessary the best for the street. For a lot of people, 2 piece rotors are overkill. They look awesome and drool worthy, but kind of pointless 95% of the time for a multi purpose car. A dedicated track car is a different story.

Almost all rotors crack at some point under heavy heat fatigue conditions. A full weight track Z generates a massive amount of heat in the front brakes and you would need lots of airflow (at least two 3" ducts) to keep them at an ideal temperature. The issue with drilled rotors is that they tend to crack sooner than a solid rotor would at the same conditions, and the small cracks that start off in the solid rotors play connect-the-dots on the drilled ones. The OEM drilled rotors on the Z06 are a perfect example of this. If you can keep the temps low enough then drilled rotors would be just fine, it's the thermal expansion and cooling that is the problem.

I also agree that 2-piece rotors are overkill on a multi-purpose car, cost savings are a myth, and full floating systems are noisy and problematic for the street. You can tell if a car is show or track by looking at the calipers, if the paint is bright and clean then it is show, if the paint is discolored and weird, then it is track ... except for Mike's because he powdercoats them after each event :)

Would you guys be interested in a two-piece option from AP Racing like this.

http://s7.postimage.org/epwloagl7/IMG_0573r.jpg

:yum:

:iagree:

If you are going to spend the money on a 2pc rotor setup you should do one that is full floating if you really want it to work as advertised.

http://www.motoringalliance.com/gall...m/DSCN1717.JPG
or this style
http://www.bonedaddy.net/Fishey/Work4.jpg

I perfer the top style because there is less chance of a hat failure IMHO.

Also, the bolts on the top one should be safety wired.

2pc rotors like others posted in this thread that are simply bolted to a aluminum hub don't offer nearly as many benefits and are prone to failure when tracked hard. They do not allow for expansion at the hub joint and as a result can cause fractures at the hub resulting in failure. They also do not help at all in preventing knock-back on the pads that all sports cars see as a result of hub-flex. This is even more true if you are a hard driver and really push the curbs as they cause a great deal of deflection.

A pretty cool video showing some deflection from curbs on F1 cars. (No one takes these kinds of footage from normal race cars! To bad cause its pretty sweet!)

http://www.streetfire.net/video/f1-in-slomo_695288.htm
-Your Pal
Fishey

Not entirely true. You dont need to have the bolts wire locked. However the AP Racing kit above does have bolts which allow you to do so if you would like. Those are the same bolts and hardware that is supplied to 70% of the Nascar field and have not seen one single failure!

AP rotors pictured above are full floating at a float of .25-.30mm and since that is the only picture posted on this thread I will assume your comments are directly related to it which I will have to point out are incorrect. This is a true full float system, it is not bolted. The second picture is a float in bell system and is even better at radial and axial float but it is not as ideal of a system on a street car because of possible excess wear on the bell.

Stoptech rotors come with the hardware. At least my replacement set did. I got probably at least 12 days on them. Replaced due to minor stress cracks, but probably didn't need to yet.

Yeah all stoptech rings come with replacement hardware.

You should not be worried by small cracks less than 4-5mm is acceptable. However if you have cracks starting from the ID or OD of the rotor ring it MUST be replaced.

I will agree with above. You will expect to pay much more for Brembo, AP, and Alcon rotor rings but generally speaking they will all outlast parts from Stoptech and smaller manufacturers. The money spent on one AP rotor set is a high initial cost but in the long run saves you money.

I think thats mostly for looks, the percentage of high-end sports cars that actually see serious track duty is as small as any other type of car, probably less than 1% of drivers actually go to the track.

HaHa! My stoptech trophys are hard anodized and they stay nice looking. Before that, I just powdercoated my calipers satin black because thats what they were gonna be anyway!

This is how hot one piece rotors and stock akebono's can get. XP12 pads were used. You can see the powdercoat melted around the hub and discolored on the spokes of the wheel. What you can't see is the runs in the powdercoat on the spokes also.
http://sphotos-a.xx.fbcdn.net/hphoto..._5796157_n.jpg