New race pads?
 

I know we have discussed this occasionally but it is time for new pads. I'm not driving much these days but i'm willing to try something new. hawk dtc60 is works pretty well. I cranked the bias valve and turned down the front shocks a few clicks to comp for the slippery hard braking zone at the local track. that said I was going easy on brakes to avoid a flat spot on the long straits. perhaps I should stick with what I know and continue to dial it in. or i can try a new compound.. in the pcar world we were all padgid, played with cobalt friction with success running old b type Acons on Audi along with carbotech for custom compounds. consitering the progresses, and the limited time I have to devote to the hobby, might just order anther set of dtc 60s. my bigger issue is learning to drive fast without power steering. I'm thinking about putting it back on but perhaps a professional alignment and Corner Balance should come first.

I've only ever driven Miatas on Carbotechs and was very happy with the feel and bite.

The shop I work for uses exclusively Cobalts. Everyone loves them. Zero bedding issues and feel out of the box. Really love how they have an optimized pad so you get a tiny bit more friction surface without any pad hardware. Makes pad swaps that much easier. Although I don't think this is exclusive to Cobalts.

Never tried the DTC 60's. Savington loves em and seems to do real well with them.

I ran and liked the Carbotech XP12&XP10's. The only downside was bedding is a PITA. They also seemed to wear out really quick. I currently run Cobalts XR2&XR3 and would be hard pressed to switch to anything else. Zero bedding issues, great modulation and long life.

Second Cobalts. They just work. No bedding or transfer layer contamination issues. I run XR1s in the front on the wilwoods and XR2 in the rears.

Again for Cobalts, haven't found anything to match them in performance. You get what you pay for

my feeling is that one should ref the pad compounds at a min in their reply. perhaps basic car set up.. I know these things have been discussed before so I appreciate the comments. any one try the gloc pads 949 has on their site?

Years ago I did the bed in procedure for cobalt late at night, it was fantastic sparks pushed out via brake ducts on an audi a4 really freaked out the the other road users, i'm talking a 4" grinder on steel aiming at the rear view mirrors. it was great. during that time I talked to a guy.. Andy Lin come to mind, no idea if that is correct, it was 10 years ago but he was very nice and interested in feed back, and called me the next week to follow up. who does that! it was a great pad but at the time is was only available in a thinner 12mm fitment for my caliper and the competition had more material so I went a different route. I will certainly consider using their product again.

carbotech has done some nice work as well. they made me custom race pads for my a4 back in 2000 ish. I was just starting out and my instructor at the time could not believe I was on stock brakes + race pads & vents. it was a pretty fun time for sure.

Just swapped carbotech XP10 for G-loc G10 and they are better in quite a few ways. The G-loc don't have a groove in the center so they don't squeel quite as bad the carbotechs. The Carbo's dusted really badly but so far the G-loc isn't as bad. Pedal feels firmer but we'll see how they do at the next track session. At temp the Carbo's have a spring feel to them, not mushy but there is some travel to the pedal which once you're over the odd sensation makes them easy to modulate.

Thanks for the feedback on G-LOC Bronson. Given the cast of G-LOC and 949 involvement I would be open to trying them.

My car:
2583 with me in it, fullish tank, no hardtop.
Xidas 900/500. Poly/bronze bushings.

Ran the car last weekend without functioning abs, so the bias is whatever is built into the NB2 abs system when it's not actually functional. Sport brakes rear, TSE 11.75 fronts with AP racing j hook rotors.rotors. XR1 FRONT, XR2 rear.

Other than abs not functioning I can say this is the best my brakes have ever felt. Solid pedal, no drama braking.
The abs issue is now resolved but that's unrelated.

I used carbotechs for years and loved them on stock brakes. When bedded properly they work well and are easy on rotors, even cold. I switched to Cobalt because after I switched to the 11.75 front brakes, I could not generate enough heat in the bedding procedure on the street to bed them properly. I tried three times and ruined three sets of pads. My fault, not carbotechs, but that gets expensive fast. At least expensive for Miata drivers. So I switched to cobalts. They aren't picky and they work extremely well.

That's interesting. I was temped to try that combo but felt it maybe to aggressive for my 11.75 V8R Stoptech/Sport combo, 2,200lbs with me in it. That maybe the direction I go when I switch to manual brakes.

One might say that if the brakes pad choice is too aggressive, one isn't driving hard enough :)

Jokes aside, the XR1/XR2 combo seems to work well for me. I will be completely honest here, and mention that I have always had ABS in my track car until this past weekend. So threshold braking without ABS was new to me. I had a couple of small lockups when the inside front was less loaded; otherwise it was drama free, although I could tell that I was more careful to brake in a straight line and then turn in with perhaps some threshold braking compared to before. I have a reputation, others have conveyed to me, as a late braker / hard charger, so I'm pretty confident I am working the car hard.

I vote try them. There's some caliper temp paint info I got from Hustler I can send to you, if you want, you can see how hot your calipers are getting. Your track car is a bit more serious than mine.

What are you running for tires Mobius? I run the S80's. Pretty light combo that locks up easy. I'll still try the XR1/XR2 combo but feel that's best reserved for manual brakes.

I did manage to lockup my setup once going into a corner too hot. Even with all the power I have I prefer stealing apexes with late braking. Something only possible in a car as light as mine. Next best is over under passing. Defend if you will, your compromised line will now cost you corner exit speed. I'll set you up for the pass then.

Möbius' choice of 1/2 is very aggressive. FYI, SM runs 3/5 iirc.

On my 240 then 310 whp turbo track car I was running a xr2 front Xr4 rear. No ABS, AP racing front brakes with 1.6 rear brakes.

Does nobody run Raybestos ST43's? They bite much like the Cobalts except their torque curve seems flatter over the temp curve and they last FOREVER! We run them in endurance racing and get several races out of a set of pads with no ducting.

I really don't understand how so many people have trouble bedding Carbotech's. I could bed them on the street in an NA 1.6.

LITERALLY all you have to do is:

Continuous 70-10 stops, do this until the brakes stink and the pedal starts getting soft, let them cool.

Done.

(or the way I've ever bedded any brakes on any car or motorcycle and never had an issue)

When I was running NB sport brakes, I did this several times without issues. No problems bedding the brakes.

When I switched to 11.75 wilwood brakes in the front, I was no longer able to get enough heat into the front rotors on the street. I'm in the middle of an urban area. Road and room and traffic allowance for multiple 70-10 stops in a row is basically non-existent. The 11.75 brakes generate more braking torque and have a higher thermal capacity. I went through 3 sets of front pads trying to bed them only to destroy them the first track day. Not carbotech's fault,

225 Toyo RR on 9's.

It is. I purchased pads based on what I'd need with the turbo on, not naturally aspirated.

I'm liking PFC. Based upon everyone's description of Cobalts, they seem similar.

Another happy Carbotech user here on sport brakes. XP10 front and XP8 rear. Enough bite and very linear response throughout. Long lasting and gentle on rotors. I can't think of a reason to try anything else.

I got 9 track hours out of PFC 01 fronts on 11.75 front, PFC 11 sport brake rears still have 75% left on them, very easy on rotors and good cold performance so you can drive home with them
Going to try porterfield R4-s pasd this weekend

We use PFC 97's and PFC11's (depending on availability) on our Chump Car and love them. Great feedback, easy to modulate, and not an aggressive initial bite (cuts down on flat spots). We easily get a 14-16 hour race weekend out of a set. Usually get another 7-8 race out of them after that. On my HPDE car, I usually get 2-3 full weekends out of them. Heating up and cooling them down kills their life expectancy.

Went from Carbo's (10/8's) to GLOC's (10/8's) on my SM this season, wow that was a learning curve.

The GLOC's have a good amount more initial bite, you really need to sharpen your pedal feel quick or you'll be doing 200ft lockups. Dust wise they are about the same, I see no significant difference.

I thought about swapping back to my carbotechs but after a few events I've gotten the feel of the GLOC's down so I'll probably just stick with them now.

I thought the G-Locs were basically clones of the Carbotechs (same compound).

I've run the Cobalt and PFC and like them both quite a lot. My complaint with the Cobalt is the large rivets take up usable pad thickness, like 1/3 of it. Bonded pads like the PFC give you more life for the $$$. But these newer generation compounds are great.

Those rivet are soft brass. They won't score your rotors if you get into them.

I like to change my pads right about that point anyway. The heat transfer to caliper gets greater when there is less pad left. That last portion also contains some of the bonding chemical and tends to behave differently than the first half of the pad.

I have run Carbotech pads, way back before the current company owned them, the Hawk DTC pads (combination of 60 and 30 front and rear) and the Cobalt pads in my track car. My car sees similar abuse to an endurance car in that my Dad and myself share the car and one of us will run the car in one session and the other will run it in the very next session so the car sees very little break during the day.

I have zero experience with the current offerings from Carbotech and the pads I have run from the older company I would not recommend.

Hawk DTC pads are what we currently run on car and are very happy as the car does see street use and the DTC compound works at lower temps.

Cobalt Spec Miata pads are very good, but you need to be cautious when you get down to the end of the pad life, as they can start to crack and delaminate from the backing plates. Another note about the Cobalt pads is that they are designed to be run without the metal shims that a normal pad rides on to help aide in quick pad changes. A word of caution, if you switch from the Cobalt pads to another pad, remember to install these shims. I had a scary incident where my Dad changed the brake pads over to the Hawk DTC pads and did NOT install the shims. I was going into turn 1 at Sebring when the brakes almost stopped working, long pedal and hardly any brake force. I was able to get the car slowed down enough to make the corner and brought the car back to the pits. What we found when we torn the car down was down right scary! The pad moved enough without the shim to drop out of the slot that hold the tab on the pad (Thanks Sebring Turn 17!). So when I stepped on the brakes, the tab on the end of the pad was outside of the caliper bracket and only the rear section of the pad was making contact with the rotor. My pressing of the pedal harder and harder, actually bent the backing material (See attached picture).
Attachment 180513

The rivets on the Cobalt pads left grooves in short order, brass or not. It looked like there was plenty of pad left to finish the second half of Sunday but there wasn't.

If you're down to the rivets you need new pads, plain and simple. We usually do 1 set of rear pads/rotors a year, and one set of pads last ~8 hours. Depending on the track sometimes we can reuse the front
rotors, other times we'll need new rotors. The cobalts will work amazing right down to the backing plate, we've done it a number of times.

If you're not choosing cobalts for rotor wear reasons, you need a hpde pad, not a race pad. VERY different requirements.

^ Troof

I don't think you understand what I said. I said 1/3 of what appears to be pad thickness is unusable because it's stuffed with rivets. Not what I'd call a bargain.

These pads only looked about half worn or maybe a little more from the top but there was an awful grinding metallic sound and it was eating the shit out of my rotors. So I pulled them out to inspect and lo and behold I was grinding the tops off of gigantic fucking rivets. So this means that if I decide to run a Cobalt pad I need to stay at least an eighth of an inch off of this thickness which means that I'm using about half the pad that I would if I had to stay an eighth of an inch off of one that was just bonded. Does that make any sense to anybody?

*eighth of an inch by eye is my emergency minimum.

Not to mention the chunking you were getting.

For comparison, this is how thin you can run carbotechs.
https://cimg5.ibsrv.net/gimg/www.mia...3988890981.jpg
https://cimg2.ibsrv.net/gimg/www.mia...90ec766a05.jpg

Brakes felt fine on the last lap on track, I knew I was pushing my luck. What's interesting is the pad taper you see here, it's not typical pad taper in that the leading edges is cooler than the trailing edge. This was caused by the caliper rotating on the pins, wearing the trailing edge on the back of the caliper and the leading edge on the front pad. It's not a lot but enough to want non floating calipers.

Seriously, you all need to try the ST43's

They are the best kept secret in pads.

Something else is going on there. I've never seen chunking like that and I've run my pads a whole lot thinner. Curious about rotor size, temps etc. Also what compound.

If the PFC's don't chunk like that then you got a solution that clearly works. We had great results with em on the E36.

Makes sense to me. Based upon the amount of pad material as seen from the top of the pad, I would not have changed those pads either. They look like they have several track hours of useful life left.

It's been a couple of years, but the chunking may have been damage that occurred when I was using a Flathead screwdriver to lever the pads back to leave room for the insertion of new pads. I seem to vaguely recall removing them to inspect them and then returning them to the caliper to assist in gently leveraging the Pistons back.

We run our cobalts down to the level of the above carbotechs. Greddygalant corrected me, we actually get 16 hours on our fronts. Chunking happens, just like the pictured carbotechs.

I would see the same chunking on the Cobalt pads on my car as well. One of the reasons we switched from Cobalt to the Hawk DTC pads. It sucked too as Cobalt is only a few miles away from my house.

Interesting. I specifically switched away from Hawk DTC60 in the front because of chunking. That and the non availability of proper rear sport pads, having to use non-sport pads, having therefore a different wear area on the rear rotor, all that and the fact the rear pads failed on me.

So we have several different first hand accounts of people moving away from different pads to another because of chunking, and it's all the same group of pads. Looking at sixshooter's photo, I get way more wear out of my front Cobalts iirc before I hit the rivets. I will monitor my current set and report back when I do hit the rivets with pics and measurements. Six how old is that photo?

I've noticed that when I compress the pistons all the way in, and put in new Cobalts, there's quite a bit of play. The next time I order I'm going to ask for 13.5mm instead of 12.5 mm. They can make the pad to whatever thickness you want if you let them know.

Do they not still offer the pre-bedded option? Beside the point I guess if you're happy with Cobalt.

Pic was taken 1/9/16. Pads would have been purchased in the fall of '15.

I bought the pre-bedded pads, that was not the problem. Getting the proper heat into the pads and the rotor to lay down the initial transfer layer was the problem. If the carbotech transfer layer isn't laid down properly, the pads will eat themselves up in short order. As in, a single track day short order. In miata money, that's expensive. 949 has pictures of rotors with a proper transfer layer vs ones that are not proper.

I don't want anyone to think I'm bashing Carbotechs, btw. I used them for years and liked them. I would continue to use them but for my stated inability to get them to bed to my wilwood rotors given the urban constraints I have. I would recommend them to anyone who can properly bed their rotors. Properly bedded the Carbotechs will give longer pad life and can be used on the street without destroying the rotors and pads if one doesn't mind the squeals and the dust. I would also recommend Cobalts. Not the same pad life, but not finicky at all. Reliable, easy to modulate, don't care about transfer layers.

Also, nice thing about the Carbotech's is the dust won't mess with the finish on the wheels.

I did one track day where the first few sessions were wet, so wet brake dust dried on the wheels and sat there for 8 months until I could get a different engine in the car and take it back out.

Dust washed right off the wheels and didn't damage the finish.

I think if the dust gets both wet and hot (e.g. track day in the wet) the resulting dust paste will bake onto the wheel. It's happened to me with two sets of wheels now - perhaps three, but the third set is black so I don't notice as much. I think I'll need a grinder wheel to remove the residue. XP12s in front.

Happened to me once as well. You may have success with a plastic scrubbie. I always wash my wheels that night or the next day, now, for a few reasons. 1, clean wheels. 2, I inspect them as I do this. 3, they get stored inside, so they need to be clean.

Carbotech pad dust has damaged the paint on my Advanti rims. It is nowhere near as bad as what Hawk pads did to past rims, but it is there. Best to clean them after every track day if you are worried about it.

Wow, that sucks. I never had that issue. Perhaps it was just 1.6 with Wilwoods at all for corners on a relatively momentum track, I just wasn't getting enough heat in the brakes to really get the wheels hot.

At Hallett in a 1.6 there is only 1 really hard braking event per lap.

lots of interesting info here. I made some adjustments on my car and found the results to be positive enough to justify another set of dtc-60 front and rear. I'm sure another pad might be better but I've been on this ride before and spending a much of of money on pads only to discover they suck for me is not an immediate priority. I believe with further adjustments to the car, and a price a tick over $200 for front and rear pads is enough to continue down this road a bit further. the fundamentals are there, feel, pad wear, price are all good. for now I blame excessive front bias and no suspension corner balance, perhaps overly firm front shock damping for my issues. the dust is not THAT bad, way better compared to other materials. my advise is to use a spray on wheel wax, brake dust repellent to protect the wheels. it is super easy to use and adds a layer of protection. if my wheels cost $1000 each I might be a little more concerned about finish. I honestly might consider powder coating the wheels brake dust gray and just avoid the pending doom of cleaning my wheels after every event. I think a deep dark gray might be decent look. Konig for one, has such a color.

I also run 11.75" carbotech / G-loc pads and have no problem bedding them in / heating them up on the road. Mainly because I extend my 3-4 70-10 stops with both brake and accelerator.

Get the pads hot and slightly stinky (carefully) and consider it done.

My issue with G-locs is that the inner curve of the (edit) PAD isn't cut to suit the rotor so have to use a bench mounted belt sander to create the inner curve. I ruined a set of rotors and had shit braking another time before i realized the uncut inner curve was leaving the mountain behind after wearing away the pad surface and causing heavy dragging on the outer edge of the rotor.

Reluctant to change but is just a hassle to do (not to mention unhealthy brake dust going everywhere while sanding). Also had the dry/wet/dry brake dust bake in to the corners of advantis too... bloody annoying and VERY hard to remove (scotchbrite and elbow grease mostly worked).