RedLS1GTO

For one weekend this summer I tried a set of Carbotech (XP12 front/XP10 rear) pads instead of the Wilwood that I had been using.

Here is as much background info as I can think to give... The car was on 315 series R compounds. As far as performance goes, I am usually in the 2:0X range at VIR without really pushing too hard. The calipers are Wilwood SL6R.

I used the pads below for about 3/4 of one HPDE weekend at VIR. The rotors were brand new. The pads were bedded 100% according to the Carbotech instructions.

Fron the start they did not feel like they had nearly the stopping power that I was used to out of the Wilwood Polymatrix A pads that I had been using. Within about 45 minutes of (mostly easy) track use they had started to groove the rotors to the point that you could see it as well as feel it. I used them for a few more 30 minute sessions on the car and they only got worse from there. It is hard to see from the pictures but there are chunks of pad that are missing on pretty much every edge and they are very badly grooved (as are the rotors). Both the left and right sides look identical so I am about 99% sure it isn't a caliper issue.

I have used Wilwood pads with the same type of rotors both before and after I used the Carbotechs and have never had an issue. I also get about 2-3 times the life out of the Wilwood pads than I got out of these. I know many people on here use Carbotech pads with great results. My friend had them on his C5 Z06 the same weekend and loved them. Quite a few different racers who use the pads and have more experience with them than I do looked at them as I was having the problem and all said that they have never seen anything like that out of them before. The end result is that the pads are pretty much trashed as well as what were brand new rotors. For comparison, I used one set of rotors for the entire year previously (which are still in great shape) and have been able to get at least 2+ full HPDE weekends on the Wilwood pads at the same track, with the same driver, same driving style, etc. Are Carbotech pads known for short life (and being hard on rotors)?

Has anybody seen anything like this or have any idea what could have caused it?







Thanks in advance for any insight.

Sidney004

This isn't an answer to your question but the second picture of your pad looks like a radial taper which indicates that the caliper has thermally spread. You should measure the parallelism of the mounting faces of your brake calipers with a vernier caliper to confirm that your brake calipers are not distorted.

RedLS1GTO

I haven't measured it, but I have used the car (with Wilwood pads) since this happened and they were absolutely perfect. There was no grooving, no uneven wear, and none of the tapering that is obvious on the Carbotech pads. There was also zero issue before the Carbotechs. From the first lap, they felt "different" and they started to groove up the rotor almost immediately.

brkntrxn

Interesting. I too run XP12/XP10s on my C5Z06 and do not have any issues. In fact, I have been running Carbos for years on multiple cars because I like them so much.

Have you contacted Danny at Carbotech about this? I run in the 2:08 range when pushing it (TTs) at VIR and I can usually get pads to last multiple weekends on Full Course.

I wonder if something happened when you bedded them in? Not saying you didn't do it correctly, just thinking out loud. I had a set a couple of years ago that I attempted to bed in when it was too cold and I never got enough heat in them. They acted funny until the first session or two and then were fine.

drivinhard

They don't. The "A" is a pretty awesome pad (ignoring dusting/noise/rotor wear issues). In terms of just sheer track performance, it is the best brake pad I've ever used. When Gary @ Hardbar post those brake caliper and pad listings for the cup teams at the road races (glen and infineon), there are several of the teams that run the WW "A" pad. IIRC, it is actually a raybestos compound.

argonaut

Hi Brian - Just a data point on my experience with CT pads: I've used the XP10 pads a lot and really like them. I don't find them to be harder on rotors than any other pads but I do think they have a little shoter life than some of the Hawk pads for example. The one time I tried the XP12 I found they wore unusally fast and didn't really like their feel...never tried them again. Brad

PS: you are in Kentucky now? PCS move?

RedLS1GTO

your reply is exactly why I am so confused... I know a LOT of people that love the Carbotech pads and swear by them. I mentioned before that the guy I was there with bought pads at the exact same time I did and absolutely loved them. As you can see, I wasn't even remotely close to getting them to last multiple weekends.

I haven't contacted Danny. I have sent a PM to Adam here on the forum but haven't heard back yet (just sent today).

I have thought that something might have happened during bedding but even then like you said, usually it would only cause an issue for a short time and even in the worst case shouldn't ever cause the grooves like it did.

That's interesting. I really don't know why but for some reason I always thought that most viewed the Wilwood as a second tier pad. I think that from now on I am going to stick with them. The only reason that I switched this once was that I couldn't get my hands on a set fast enough (poor planning on my part) for my trip to the track. Do you have any experience with the B compound? I'm not setting lap records and I have thought of trying different combos to see if I couldn't make parts last a little longer. The dusting and noise are no biggie to me but I would like to use rotors as long as possible. Of course the Carbotechs absolutely destroying a set of rings in a day didn't exactly accomplish that...

I'm actually glad to hear that some other people haven't liked the feel of the 12s and I'm not completely alone in that. I was averaging a couple of seconds a lap slower with them because I wasn't comfortable enough and confident enough to drive deep into a corner with them.

I am in Louisville now... I'm also a civilian. It came to be decision time to either stay in for 20 or to try something new. I decided to try something new. I'm not 100% sure it was the right choice but I'm getting used to it slowly. Corporate America is a big change from the military life that I have been used to for my entire adult life.

Sidney004

As mentioned earlier, Wilwood race pads are made by Raybestos; their race pads are first tier. I am not sure if the "A" is exactly equivalent to the Raybestos ST43, but my experience with the ST43 was very positive.

brkntrxn

I agree that 12s will wear quicker than a lot of other compounds. My all time favorite pad is the XP10 since I think it gives a good compromise to stopping power versus longevity. I run the 12s up front due to the higher heat range I encounter in the Time Trial flyer laps we run. Threshold braking in every single turn for 4-5 laps will fry some of the lower heat range pads.


-Kevin

96CollectorSport

I know you said that you bedded the pads in per CarboTech's directions, but I've had instances in the past were I didn't get the pads/rotors hot enough during bedding and the results were similar to what you got. We typically run Hawk DTC-70 and StopTech 2 piece rotors. We tried using a set of Raybestos rotors with some used pads and just didn't get a good transfer layer onto the rotor face. The pedal was solid but the car just didn't stop like it usually does. Put a new set of pads and rotors on and bedded them in and everything was fine again.
The bedding directions are a guidline, you still have to be able to read the rotor and make sure there is a good even transfer layer on the rotor face. Without that transfer layer the car just won't stop like it's supposed to. Just my $.02

0Todd TCE

I have to agree with drivinhard here. And not just because I sell them.

The A pad is still pretty much a bench mark for track performance. Yes, I'm sure there are some today that are close/similar/maybe 'better' in some manner. But for anyone who's ever used the A's they'll tell you that they are predicable, consistent and responsive. When used on the right app- meaning not on the street, at a serious race temp and with tires capable of generating the necessary grip the pads can generate.

The cup marks are not uncommon on the pad but those appear to be even a bit more pronounced then normal. The radial taper coming from a combo of temperature fluctuation across the rotor and my guess; probably some caliper flexing from the continued effort being sought by the brakes to make up for the lack of bite. Meaning the whoa was not what it was before so you upped the pressure into the caliper in an effort to make up for it, a natural reaction.

I can't say that the comments about pad transfer layers in bedding and swapping pads is totally wrong either. From experience moving from a PFC pad to the Wilwood line I've see it before also. The former having put down a carbon layer that the Poly pad just slid over the top of! Rule here: be certain that you know what you are moving from or to is compatible with each other.

RedLS1GTO

That makes a whole lot of sense.

The rotors were out of the box new so it wasn't a matter of incompatible with a different pad in this case.

Thanks for all of the answers. There is a lot of good info being put out there by people that know a lot more about brakes than me. Although everything looked to be good after bedding, I'm guessing that I just didn't get them bedded in as well as they needed to be. That's really the only consistent answer at this point.

brkntrxn

Todd's explanation makes a LOT of sense as well. If you were pushing the pedal harder because the XP12s do not have the bite of the WW As, then that would explain a lot.


-Kevin

RedLS1GTO

You sell them huh? Hmmm... got any Holiday Specials??

I can't say for sure that I was pushing the pedal harder but I wouldn't at all doubt that I was.

90pololt4

Do both sides look like this or just one? If it is just one side, I have seen debrie get in side between the pad and the rotor and cause the same look. Usually when a wheel is off the pavment and kicks up stuff. Hope the real cause is found. It's big relief when one has no worries.

RedLS1GTO

All 4 front pads look pretty much identical so probably not debris. It is definitely a much better feeling to know that when you push the pedal you are actually going to stop.

0Todd TCE

Not truly knowing the Cf of the other pad, compared to the Poly A pads.....so some of this is a bit of speculation....

If it's a half point lower or so and 'maybe' not capable of dealing with quite the level of heat you put into them (*they appear a bit chalky, but admit it's hard to say) you'd be boosting the leg requirement and thus psi up 10% to get back to the total rotor toque lost. The heat combined with the added stresses being put on it can force the caliper to be flexing more than it should be.

Caliper model used here is? 8000 series with 16mm pad? Or is is the full size 6 w/20mm?

RedLS1GTO

They are Superlite 6R calipers with the 16mm pad.

drivinhard

I'm always amazed at how everybody gets different rotor/pad wear experiences with the same compound. In my experience, carbotech has been the most rotor friendly track/race pad I've ever run. Wilwood "A"s were the hardest on rotors (I used to use up 2, sometimes 3 sets during 1 lifespan of pads).

My experience with the "A" pad was several years ago, and not in the corvette. I have run mostly carbotech 12/10/8 in the TTA car. IMHO the XP10's are 99% of the torque and bite of the Xp12's, but they last way longer. The 8's are even better on wear and they work well as a rear pad. All the carbotech makes for friendly brake dust, you could let a set of wheels sit forever and they always wipe right off. During my wilwood "A" days, if you didn't get the dust off the wheels right after a session, it became part of the wheel

So the "A"s dust terrible, and you don't want to leave it on your wheels, they squeal something terrible, they eat rotors like a lathe (if you need to true up some rotors, just go for a few laps). In light of all that, if I was in any race I cared about, that would be the pad I'd run without blinking.

0Todd TCE

Suspected that.