Brakes Revisited

[Grant 302]

Those M3 rotors are normal, lots of face-checking/cracking...it is unavoidable. The drilled rotors...it's tough to say from those photos if those are only surface cracks or not, but I don't like that there's one at each drill location.

Always avoid drilled rotors, IMO.

^this.

I'd take those off now. Those are the 5000XS. I'd get new rings in either (old) 6x6 or the new T3. KNS has them in stock?

 

[Grant 302]

I agree. However, now that I think about it, has anyone ever considered split rotor styles? Heavy OEM blanks up front for max thermal capacity, drilled rotors out back for light weight, since they aren't doing anything anyway?

Considered it, since we don't have any readily available cooling solutions for the rear. But the problem is that I've seen too many internet pics of cracked rotors at the drill holes. Shouldn't be as much of a problem at the rear, but a cracked rear rotor will put you in the wall just as fast as a cracked front rotor...so why take the chance?

 

[2012YellowBoss]

Those M3 rotors are normal, lots of face-checking/cracking...it is unavoidable. The drilled rotors...it's tough to say from those photos if those are only surface cracks or not, but I don't like that there's one at each drill location.

Always avoid drilled rotors, IMO.

What he said, my front Brembo and Powerslots look like the M3 rotors after a few runs. The cracks look very scary on the drilled rotors, I have heard the same about drilled rotors and never used them. I did see a set of drilled rotors on the 59 at Daytona and did not see any cracking on them. Wish I would have taken pictures of them, I would like to know the story behind them.

In your case I would get off the drilled for now and see what kind of wear you get with blanks or slotted.

To the extent this is helpful, I run Performance Friction 01's up front and 06's out back on my 2011 GT. The rears obviously last for a long while whereas the fronts last me (I wish I took better notes) around 5 track weekends. This is on stock rotors. Rotor wear is not bad for me, either, and I'm running a set of Brembo's that come on the car (on my second set of those rotors).

That is really good wear, I will go through a set of 01 in a day and half. I got three days out of the last set of 08's, one at Daytona at two at Sebring. Sebring is hard on pads and when they hit the 60% mark the wear very fast, in other words I can get at least two days on the first 40% and just a few runs on the remaining 60%. I saw the same thing but at a faster rate with the 01's.

 

[Teamsketch]

^this.

I'd take those off now. Those are the 5000XS. I'd get new rings in either (old) 6x6 or the new T3. KNS has them in stock?

Thanks for the heads up on KNS. I will check them out if I go with new DBA rings.

However, this time I'm leaning toward going with some regular slotted rotors. I tried finding the Power Slots but everyone I checked is out of them. Does anyone have any leads on slotted rotors that are available now?

 

[2012YellowBoss]

Thanks for the heads up on KNS. I will check them out if I go with new DBA rings.

However, this time I'm leaning toward going with some regular slotted rotors. I tried finding the Power Slots but everyone I checked is out of them. Does anyone have any leads on slotted rotors that are available now?

Some places like Tirerack or Buybrakes don't stock the fronts in Cyro they special order them. They will stock the non-Cyro 126.61089SL and R (C is cyro, S is slotted and L-R is left right). Best thing to do is search the with only the part number 126.61089CSL

Here is an Amazon link showing them in stock:
http://www.amazon.com/Centric-Parts-126-61089CSL-Slotted-Brake/dp/B003K2RY90/ref=sr_1_1?s=automotive&ie=UTF8&qid=1359675962&sr=1-1&keywords=126.61089CSL

Prices have gone up since I last bought them. If this place is for real they have them at 107 plus 45 shipping, best I could find. Says they are in stock but I would call and check.

http://mibearings.com/brake-rotors-c-8/126-61089csr-power-slot-cryo-rotor-822903525714-p-8702

 

[Teamsketch]

Some places like Tirerack or Buybrakes don't stock the fronts in Cyro they special order them. They will stock the non-Cyro 126.61089SL and R (C is cyro, S is slotted and L-R is left right). Best thing to do is search the with only the part number 126.61089CSL

Here is an Amazon link showing them in stock:
http://www.amazon.com/Centric-Parts-126-61089CSL-Slotted-Brake/dp/B003K2RY90/ref=sr_1_1?s=automotive&ie=UTF8&qid=1359675962&sr=1-1&keywords=126.61089CSL

Prices have gone up since I last bought them. If this place is for real they have them at 107 plus 45 shipping, best I could find. Says they are in stock but I would call and check.

http://mibearings.com/brake-rotors-c-8/126-61089csr-power-slot-cryo-rotor-822903525714-p-8702

Sigh...yes I had already found them on Amazon then forgot about it. My mind is going today.

 

[2012YellowBoss]

Here are some pics of different rotors I have use. I am learning like many here and don't claim to be an expert but these pics will show why I said what I did. If I was racing it would be totally different but for track day fun I try to get the best bang for the buck.

Powerslot Cyro rear w/PFC97 after two days at Sebring. Did not get the chance to season or bed these in, mounted and straight to the track..



DBA4000 rear w/PFC97 with 3-4 days




Front Brembo, more then 15 days but used when I was learning and a non-aggressive type pad. I had so many days on these I retired them. Then a friend came over to help out with a weekend at Sebring, he took them out of retirement saying they were fine and I put two more hard days on them with the PFC08's



Powerslot Cyro front with 10 or more days, not exactly sure. These were cut once.



and last a set of DBA5000's w/PFC01 and 08, four days, not sure if I should run them again because of the long crack getting close to the edge. I welcome comments on the future use of these ....

 

[cloud9]

Those M3 rotors are normal, lots of face-checking/cracking...it is unavoidable. The drilled rotors...it's tough to say from those photos if those are only surface cracks or not, but I don't like that there's one at each drill location.

Always avoid drilled rotors, IMO.

Agreeeeeeeed

 

[cloud9]

Those DBAs look to be on their last leg Scott. You'd be on a session by session basis with them. That said, whether it's 1 session or 10 will depend a lot on driving style and pad choice. I'm starting to get suspect about DBAs rotors. I've been running them for 4 years now. The first three years I ran them on my GT500 (400 lbs heavier) they were great. The first set I ran on the Boss were good, but didn't last as long as the GT500 (18 days on average fronts and 20+ rears). The last 3 sets on the Boss were progressively worse. 10 days, 6 days and finally warped in one weekend at Road America. WTH is going on?? I haven't tried the new T3 rotor, but is it possible they realized they were having a problem, thus the redesign? I'm almost ready to order a set of the new T3 design but am starting to wonder.... :

 

[PeteInCT]

If you're getting a "shimmy" in the wheel your rotors are either slightly warped (I assume the "Shimmy" isn't that pronounced) or you're getting pad deposits building up on the rotors. If the latter, it probably means the pads were not bedded in properly (not hot enough) but that should wear off eventually. If it doesn't then I'd guess your rotors are warped or unevenly worn.

 

[2012YellowBoss]

Those DBAs look to be on their last leg Scott. You'd be on a session by session basis with them. That said, whether it's 1 session or 10 will depend a lot on driving style and pad choice. I'm starting to get suspect about DBAs rotors. I've been running them for 4 years now. The first three years I ran them on my GT500 (400 lbs heavier) they were great. The first set I ran on the Boss were good, but didn't last as long as the GT500 (18 days on average fronts and 20+ rears). The last 3 sets on the Boss were progressively worse. 10 days, 6 days and finally warped in one weekend at Road America. WTH is going on?? I haven't tried the new T3 rotor, but is it possible they realized they were having a problem, thus the redesign? I'm almost ready to order a set of the new T3 design but am starting to wonder.... :

Thanks Gary, such a shame for expensive rotors. I have nothing against DBA but even if the price was the same as the Brembo or Powerslot they would not be worth it due to early early failure I have been experiencing. I also have a set of 4000's front I picked up at last years close-out pricing and they do not look to be holding up anything like the others. This may be backwards thinking- since heavier rotors are harder to start up at slower tracks with many turns - but I hopeing to use light weight rotors again at Daytona. If the new ones hold up under reviews here I may consider a new set of rings.

I am guessing here but I think the redesign was more about making them unidirectional then anything else. BTW, I am assuming the other companies will follow with this in the future.

 

[KNS Brakes]

Thanks for the heads up on KNS. I will check them out if I go with new DBA rings.

However, this time I'm leaning toward going with some regular slotted rotors. I tried finding the Power Slots but everyone I checked is out of them. Does anyone have any leads on slotted rotors that are available now?

The only lead that I know for sure 100% guarantee on slotted rotors at the 110 DBA 4000 rotors that I have sitting in my warehouse waiting to move.

-Nick

 

[JScheier]

Powerslot Cyro rear w/PFC97 after two days at Sebring. Did not get the chance to season or bed these in, mounted and straight to the track..

DBA4000 rear w/PFC97 with 3-4 days

Questions on the rears... are you running with AdvancedTrac on? Is everything turned off? If everything isn't off, AdvancedTrac will totally smoke a set of rear pads / rotors.

The rears look really abused (3-4 track days?) on a car that really doesn't have much rear braking bias:
* Have you taken a look at the calipers to see if either of the pistons are hanging or dragging?
* Are you left foot braking (and possibly resting on the pedal)?
* Have you pulled the rear dust shields? That will aid with cooling.

Rule of thumb... if you can feel the crack with your fingernail, it's time to replace them. The tiny micro-cracks in the PowerSlot rotors you shouldn't feel and they look pretty normal. In the last photo of the DBA rotor, you can see where the crack is actually rising.. causing hot spots (see the color change?). Don't run that one again.

PS - Gary will hate this... but I'm still on the as-delivered set of rotors on my car. The fronts are about done (micro-cracks)... the rears look brand new. Cobalt pads and OEM rotors

 

[cloud9]

I just need to buy a Miata.

 

[JScheier]

I just need to buy a Miata... with OEM rotors

Fixed that for ya

 

[2012YellowBoss]

Questions on the rears... are you running with AdvancedTrac on? Is everything turned off? If everything isn't off, AdvancedTrac will totally smoke a set of rear pads / rotors.

The rears look really abused (3-4 track days?) on a car that really doesn't have much rear braking bias:
* Have you taken a look at the calipers to see if either of the pistons are hanging or dragging?
* Are you left foot braking (and possibly resting on the pedal)?
* Have you pulled the rear dust shields? That will aid with cooling.

Calipers are fine, heat shields off, you can see the new set of rotors on the same pads in the picture above the cracked rotors. The cracked rears were run with Advancedtrac off except one day at Daytona. That day the system warning light went off early in the morning and I could not make any changes to it, the system may have been off but I am assuming it was on.

I had a set of Powerslots on the rear that lasted a long time on the rear (15+ days) while driving with the Sport Mode on. In Sport Mode I could feel the system kick in here and there but I never saw unusual wear. I only left foot automatics.

 

[Berol]

Tons of good info in here as I learn.

 

[Jimmy Pribble]

I haven't started any trouble today, so...let's get cracking! <-See what I did there?

I checked my personal library (that's books, guys...books ) last night to see if I could find any support for my 'harebrained brake bias via pad composition' theory. Couldn't find any help, however, in Brake Systems (Mavrigian, Carley), they strongly recommended that rotors be broken in very, very slowly over a period of time and never with new pads. I don't have the book with me at the moment, but I can report more details later, if there is any interest.

 

[cloud9]

I haven't started any trouble today, so...let's get cracking! <-See what I did there?

I checked my personal library (that's books, guys...books ) last night to see if I could find any support for my 'harebrained brake bias via pad composition' theory. Couldn't find any help, however, in Brake Systems (Mavrigian, Carley), they strongly recommended that rotors be broken in very, very slowly over a period of time and never with new pads. I don't have the book with me at the moment, but I can report more details later, if there is any interest.

I've read that too and that's been my practice.....new rotors/used pads. Not sure how I'm going to pull that off with the new setup I just ordered from Pete though.....new DBA 5000 front and 4000 rear and Pagid pads RS14/56. I really don't want to season the rotors with my used DTC70 pads and "contaminate" the rotors before putting on the Pagids......Hey Pete got any used pads??

 

[ArizonaBOSS]

TBH just buy the Centric Blanks...they are "Cheap" by comparison and last just as long if not longer than these other rotors.