Which brake rotor brand is better for track use?

[up4speed]

I have been using the Stop Tech Cryo treated blank rotors (non PP) with Ferodo 2500 pads, and have been happy with them. They have held up very well to the heat, with zero warping. My only complaint is that they seemed to get heat checking after 6 or 7 track days (see attached photos).
I decided to upgrade to the PP front brakes and ordered the same rotor in the larger size. But then I got thinking.....
Since FCP Euro has a lifetime warranty, I should buy from them from now on (I purchased the larger Ferodo pads from them). The problem is that they don't have the stop Tech Cryo rotors for sale. They only have the Stock OEM VW, ATE, and Zimmermann. If I wanted to have the lifetime warranty, I need one of those 3. I did also consider if it was worth using the warranty for the rotors, since shipping back will be expensive, but I'm still probably looking at about $35-$40 for shipping VS. $300 buying StopTech Cryo rotors again.
So my question is, which one of those 3 rotors are best? Will they be better or worse than the ones I'm using?
I would really like to purchase pads and rotors from FCP, this way I can get new pads AND rotors every time the discs OR the pads fail.
In my current situation, the pads have life left in them (1 or 2 more track days), but it seems like the discs failed, so I'm not happy about prematurely changing brake pads just because the rotor failed. It's not too bad this time, because I'm upgrading the brakes anyway, but I'm trying to figure out the best way to move forward. Any advice or opinions are welcome! Thx

 

[GTIfan99]

I'm using the Zimmerman from FCP euro. They're holding up well, but only have a couple dozen autocrosses and 3 track days on them.

 

[GTIfan99]

You can buy brake fluid and return it for new fluid.

The one issue is the upfront cost is over double. You need extra fluid, pads and rotors to put on the car, then send the old back, unless you can have the car off the road for the time it takes to send the old stuff back and get the new fluid, rotors, pads.

 

[up4speed]

You can buy brake fluid and return it for new fluid.

The one issue is the upfront cost is over double. You need extra fluid, pads and rotors to put on the car, then send the old back, unless you can have the car off the road for the time it takes to send the old stuff back and get the new fluid, rotors, pads.

From what I understand, you need to front the original cost, then when those wear out, you have to buy set#2, THEN once they come, do the swap and return used ones for a refund. Therefore, you don't have any down time with the car. Is that correct? Or did I misunderstand?

 

[Bernb6]

From the two photos you posted, I don't think you have any problem regarding rotor checking/cracking. In my experience, cracking becomes a problem when any crack is ~1 inch long or a significant crack reaches the edge of the rotor. In the case of drilled rotors, any crack connecting two holes would be a limit. I don't have anything against FCP but would urge you to consider other rotor options as well.

 

[Mini7]

I agree. Surface heat fatigue cracking is totally normal for tracked cars. These rotors do not look bad at all.

 

[up4speed]

From the two photos you posted, I don't think you have any problem regarding rotor checking/cracking. In my experience, cracking becomes a problem when any crack is ~1 inch long or a significant crack reaches the edge of the rotor. In the case of drilled rotors, any crack connecting two holes would be a limit. I don't have anything against FCP but would urge you to consider other rotor options as well.

What other options? I am open to look at all options. The only thing I decided is that I definitely want blank rotors. Other than that, I want them to not warp and feel like crap after 2 or 3 track days. If I can get at FCP, it's a bonus because I think it will save me a lot of money in the long run. However, performance comes first. If I can get a better performing rotor, and I have to pay, I will pay. From what I understand, it's really the brake pads that make the biggest difference in braking performance.
As I said, I really like the Stop Tech Cryo rotors. Since you guys think they are in good condition, and they still feel perfect, I like them that much more! I usually warp the rotors in most of my cars, so I count these as a win so far. Too bad FCP doesn't carry them.

 

[jimlloyd40]

What other options? I am open to look at all options. The only thing I decided is that I definitely want blank rotors. Other than that, I want them to not warp and feel like crap after 2 or 3 track days. If I can get at FCP, it's a bonus because I think it will save me a lot of money in the long run. However, performance comes first. If I can get a better performing rotor, and I have to pay, I will pay. From what I understand, it's really the brake pads that make the biggest difference in braking performance.
As I said, I really like the Stop Tech Cryo rotors. Since you guys think they are in good condition, and they still feel perfect, I like them that much more! I usually warp the rotors in most of my cars, so I count these as a win so far. Too bad FCP doesn't carry them.

Do you follow the pad manufacturers instructions for bedding in the brake pads so they don't warp so easily?

 

[GTIfan99]

Do you follow the pad manufacturers instructions for bedding in the brake pads so they don't warp so easily?

He said he didn't warp the cryos.

 

[jimlloyd40]

He said he didn't warp the cryos.

I was with the understanding and I can't remember who posted it that rotors don't warp it's the brake pad deposits on the rotor that gives the feeling that the rotor is out of round. I have 2 piece rotors and after driving hundreds of miles I'll get that out of round side to side pulling of the steering wheel that suggests the rotors are out of round and just do a couple of very hard stops like you would when bedding in new pads and the out of round feeling is gone.

 

[Bernb6]

I agree with Jim - "warped" rotors are really rotors with uneven deposits.
Here's a good write up from Stoptech on all this and more: Stoptech brake pdf
To the OP's comment re wanting blank rotors, if it's esthetics, that one thing. But if it's performance, then give another thought to slotted rotors. Virtually all race-oriented rotors are slotted for good reasons. They provide a wiping action that helps with outgassing and driving in the wet. They do not promote rotor cracking. They provide a clear, visual indicator of rotor wear as many manufacturers ground the slots to the depth of minimum rotor thickness. IMO, they do not cause noise, nor do they increase pad wear.

 

[Bernb6]

OP, BTW, here's what Stoptech themselves say about cryo:
Cryogenic treatment : A thermal process in which metallic components are slowly cooled to near Kelvin temperature and then equally slowly returned to room temperature. Proponents claim that the grain structure is refined by the process. There is considerable doubt about the effectiveness of the process. Evidence is largely anecdotal and to date no scientific and quantitated engineering studies have been published.
Another Stoptech pdf

 

[up4speed]

Do you follow the pad manufacturers instructions for bedding in the brake pads so they don't warp so easily?

I always follow it 100%.

 

[up4speed]

I was with the understanding and I can't remember who posted it that rotors don't warp it's the brake pad deposits on the rotor that gives the feeling that the rotor is out of round. I have 2 piece rotors and after driving hundreds of miles I'll get that out of round side to side pulling of the steering wheel that suggests the rotors are out of round and just do a couple of very hard stops like you would when bedding in new pads and the out of round feeling is gone.

I agree...partially. They definitely feel warped if there are uneven deposits on the rotor. But as you said, they can be fixed if you do the bedding process again. I have to admit, MOST of the time, it is uneven deposits that cause the pulsing. However, I'm pretty sure, from research as well as personal experience that they actually can warp. From what I understand, warping is usually caused when people don't tighten the lugs evenly with a torque wrench, or if they are hot and the driver splashes through a puddle. Another way is if the brakes are very hot from driving aggressively, then the driver stops at a light causing the rotor to cool unevenly since the pads are clamped on the rotor (this practice can also cause uneven deposits). To avoid this, I like to brake hard initially, then creep up to the light as they cool.

 

[up4speed]

I agree with Jim - "warped" rotors are really rotors with uneven deposits.
Here's a good write up from Stoptech on all this and more: Stoptech brake pdf
To the OP's comment re wanting blank rotors, if it's esthetics, that one thing. But if it's performance, then give another thought to slotted rotors. Virtually all race-oriented rotors are slotted for good reasons. They provide a wiping action that helps with outgassing and driving in the wet. They do not promote rotor cracking. They provide a clear, visual indicator of rotor wear as many manufacturers ground the slots to the depth of minimum rotor thickness. IMO, they do not cause noise, nor do they increase pad wear.

I have tried slotted in the past, and i had a bad whirring noise, as well as faster wear on the pads. I also street drive the car, so it's always a compromise. I just have had better luck with high quality blank rotors to this point, that's why I prefer them. Considering the beating that I gave the StopTech Cryo rotors, I have to say, I'm pretty impressed. The pedal still feels great, and considering that I had the standard brakes on the car, I'm getting great and consistent performance out of them. I'm looking forward to mounting the PP brakes with the larger rotors, because braking is like HP, more is always better, lol