FAQ: Brake Rotors and Pads

"Mating" is an interesting theory. I have another idea: race teams get brake systems replaced a lot more frequently than daily driven street cars.

Remember the pads & rotors I'm using on the Riviera have tens of thousands of miles on them. I got almost 40k out of the HP+ pads, and they worked great up till the day I changed them. A race car's brakes get replaced a lot sooner than that.

I installed a set of rotors and pads on our race team's track car, an Acura Integra, in 2009. We used the same rotors and pad combo I had on the Riviera. So far we've completed 4 races over the past 2 years, and the pads and rotors so far have held up very well. Each of our endurance races are 14 to 25 hours non-stop at 60-80 mph average lap speed. That's between 700-1400 miles per race. Many, many hard braking events, a few from 100+ mph. We never broke in our pads/rotors, we never mated them - just rolled the car off the trailer and raced. We didn't even properly bed the pads before the first race.

At first it would seem our race car's brake set up is more durable than the Riviera's, but remember it's the same set up on both cars - only difference is: the Riv is heavier and driven every day, at reasonable speeds with fewer braking events; the Integra is lighter, driven at higher speeds with much harder braking, but only about 3 days per year.

There's no way we'll get as many miles out of our Integra's pads & rotors as I have on the Riviera. At the current rate, we estimate the pads will be good to 6-7k miles, and the rotors, maybe 15k miles. That's a pretty long life for track car brakes. But when you look at the numbers, it turns out the Riviera gets much longer life from the same equipment.

If you want to know how race teams do it, read up at Zeckhausen Racing or StopTech's white pages. Racing is brutal on pads, rotors and calipers, and many teams will change the fluid and rebuild the calipers before every race or two. Rotors are considered a wear item, which is why they use replaceable rings on hats. Even the hats get replaced after a few races. Pads are replaced every few events, sometimes every race depending on the car, the pads, and the driver. In almost every case, brake parts will last longer on a street driven car vs. a high-speed racer, imo.

AA, I'm curious how many miles you wound up getting out of your DTC 30 pads?

I just finished a set on my 99 GP GTP with fbody brakes, and I was surprised that they lasted only a little over 2 months, couldn't have been more than 3000 miles tops (forgot to write down mileage ). Granted, those miles were pretty spirited. Having that level of braking power changed the way I drove and braked to a degree, and those miles / my commute had quite a number of stops from 70-80mph to zero for red lights. To put it in perspective, I ran HP+ pads before these, and they lasted a little over 2 years and ~22k miles. The DTC 30s also tore the hell out of my brand new rotors, leaving quite a ramp/lip in the outer edge. They also dusted incredibly bad, and for me, squealed about as bad as the HP+ (pretty bad). They did have amazing stopping power,though. This car is my DD, so it's not practical to keep running these pads, but it was fun while it lasted. Now I'm trying to figure out what I'll do next. Probably more HP+ pads as I thought that was a reasonable tradeoff. I'd like to do DS2500s (if they make that size yet for fbody), as I've really liked them on my cobra, but I haven't driven that car enough to know how long they will last. If they only last as long as the DTC 30s, I can't consider them.

I got almost 5k miles out of the DTC-30s, which included some long distance trips. They are worn down to almost nothing. Basically I had near exactly the same experience you had. I also had the HP+ previously, and they lasted a long, long time (outlasted the rotors), and so that's what I've switched back to. HP+ does pretty much everything I want for braking hard on the street, and they're not really that noisy on my car for some reason - I think it has to do with the way I use the pedal. I've "learned" to drive quietly with HP+.

For the track, I'd go back to DTC-30 compound, but I agree with you - they are near impossible for practical street use.

Good to hear that you had roughly the same experience as me (well, bad for us I guess, just happy that it wasn't just me). Honestly, I was a little shocked that they wore out as quickly as they did. The place I bought them from recommended them to me, based on how much I liked the DS2500s, as sort of an alternative to the HP+ that had better braking power, less noise, etc. Said they would be fine on the street, and made it sound like they were sort of a lateral move from the HP+ pads, only they had better specs. I wasn't made aware of the drastic tradeoff in pad/rotor life, though I didn't think to ask.

Live and learn I guess.

Hopefully people will read this when they are searching in the future, wondering if they are "streetable". IMO, yes, very much streetable in terms of "do they work well on the street." Very much not streetable if you're talking about using them exclusively on the street. Unless you don't drive the car much or have a budget of almost $100/month for brakes and rotors. Of course, if you also track the car, that's a whole different story.

BTW, our mods are very much similar

I said it earlier in the thread but ill say it again. Anyone looking for a set of pads with race level stopping, low noise and long life try the EBC blue stuff pads.

I have had them on my car for 6 months and 6k mile. they have a lot of life left, dont seem to be eating away my slotted rotors and still stop as well as day 1. I also constantly push them and cant get them fadded (120-0 or 2 stops from 80 with no problem)
Is there a negative to them? Yes. They have more dust than any pad i have seen and they do not work as well cold as the Hawks i had previously.
I keep meaning to pull the pads and check the wear + remeasure them but i just havent had the time. I can see through the wheels they look to be about 20% used and i hope that trend continues.

Good to know. I'm going to stay with the HP+ for now, mainly because I like how they work in really cold weather. I might decide to go with the EBC blue for track pads, and possibly a summer pad for next year. I really like hearing how they aren't eating your rotors up. The DTC-30s were ridiculous in that regard!

Just ordered HP+ replacements today.

I'll keep the blue stuff in mind for next time, but for now, I just wanted to get something tried and true.

On a side note, though, is it possible for a pad to dust like no other, but also have longevity? Kind of seems counter-intuitive. I know the DTC 30s made the dusting of the HP+ look like nothing, and the HP+ dust pretty bad themselves. I had been thinking that all that dust should have been an indicator of quick wear, but if the blue stuff pads can dust that bad and last? It just seems like all that dust is pad (and/or rotor) material that is coming from a limited supply, more dust = more wear, I would have thought.

i agree that more dust = less life from either pad or rotor.

however my rims show dust more than most due to the lip design and the chrome coating.
the hawk HPS pads i had on before dust a lot IMO

If you think the HPS pads dust a lot, the HP+ pads would redefine dust for you, and the DTC 30 would just blow you away. Imagine how much dust 2 entire pads and 0.100" of each side of a 12" rotor contains, and then imagine dumping it all out over 3k-5k miles, and you'll have an idea

Matt's right, it's either the pad or the rotor that's making that dust, and I've found it's mostly from the pads when it's heavy and black, or caked on, or a combination of both in extreme cases.

I've used the HPS, HP+, and DTC. I considered the HPS to be almost dust free, and the HP+ made a bit more. On a scale of 1-10, I'd rank them like this:

OEM: 1
HPS: 3
HP+: 5
DTC-30: 9 (saving 10 for a dirtier pad I've never encountered, but I can't imagine it)

I really don't think it gets much worse than the DTC, although I've heard Hawk Blue pads are very dusty, and they will corrode your wheels when it gets wet.

Based on the information in this thread, I feel the EBC Blue might be comparible to the HP+ in dusting, or slightly more (maybe a 6), but I think the source of their dust is different: the EBC is mostly pad dust, while the HP+ is almost all rotor dust (iron powder). I'm basing this on Matt's comment about the EBC blue pads wearing 20% in 6k miles, and my experience of the HP+ slowly wearing down rotors with almost no wear to the pads over 25k+ miles.

Of course, how you drive the car, and the car itself, makes all the difference. On our track Honda, HP+ don't wear the rotors much at all, as the pads are only used at high temps, so it's all pad wear in that case. I think these wear traits hold true with most all pads, being dependent on temperature range and driving style/application.

I wanted to add something in here. My experience with the DTC 30s may have been an outlier.

When I heard scraping, I only checked the pads on the side that was scraping, the front passenger side. They were practically down to the metal as I described. I had glanced through my wheels at the other side, but didn't bother to jack it up, because I really didn't care considering I knew I needed a set of pads anyway.

Today I jacked up both sides and changed the pads, only to find that the driver side pads had about half the life left (didn't measure, just eyeballing it). Considerably more than a millimeter from the metal as the other side was. Very uneven wear.

Both of the pistons on both sides seemed to compress normally (not sure if this is an indicator either way to them being frozen and/or causing this problem), but the lower slide bolt on the drivers side (the side with half pad life left, NOT the side that was worn out) was completely frozen solid, would not budge. I managed to free it and lube it, and now it slides normally.

So, because of the frozen slide and uneven wear, I'm not sure where I would have landed with the DTC 30s with everything functioning normally. I still don't really regret going for the HP+ again, because I had good luck with them, and I'm not about to drop another $130 to see what I get from DTC 30s when we already know that AA's pads didn't last much longer than my one side did. I'm just hoping that this set of HP+ pads wear evenly as they should.

As a side note, does anyone know if it is possible for one frozen slide to prevent the side it is on from properly wearing the pads (ie, did not wear them enough)? Searching the net seems to show that a frozen slide bolt would normally wear out the outer pad of the same side unevenly with the inner pad, but I couldn't find any cases like mine. It seems that even pad wear, inner and outer, as I have, but uneven left to right, as I have, is a sign of frozen piston(s). But both pistons per caliper, on both sides, seemed to compress about normally without any noticeable extra pressure -- does this tell me anything about whether or not one or more of them were frozen? Any ideas?

I'm not a brake guru or anything, but just thinking about it, I was wondering if having a frozen slide could prevent the left caliper from properly compressing and braking, meaning that most or all of the braking for the front would be done by the front right pads and wear those out sooner. But I don't know if this is ever the case or is even possible. FWIW, I didn't notice any particular lunging or uneven brake feeling while braking that would suggest this, I'm just not sure how else this could have happened (since the pistons seemed OK, and the slide that was frozen was on the opposite side of the problem). Oh yeah, the rotors for both sides were brand new and identical when the DTC 30 pads were installed, and both look about the same now, save for some small grooving on the inner hub lip of the passenger side that had the pads wear down to metal.

The lower slide pin being frozen, that would cause the extra wear to one side as you experienced. However the DTCs didn't wear super even for me either. I was thinking one of my calipers might have been frozen, but inspected them and no problems. One pin on the passenger side was dry, but still sliding okay (easy fix). Btw, it was my driver side that wore faster for whatever reason. Your frozen pin might have been the reason you only got 4k miles, while I managed 5k.

I've got a couple thousand on my fresh HP+ now. It's about time for an inspection, so will post pics of any abnormal wear I find. First time I used HP+ they were unbelievably even down the last few mm thickness. I really couldn't believe it, so I think my calipers are in good shape.

I think with the higher friction race pads like DTC, you have to consider there is a lot more heat transferring through the pad, rotor, caliper and fluid. It's entropy city at each front wheel. Any little thing that might cause one side to grip more or less, it's going to be reflected in how much heat is building up on the side that grips more. That extra heat will certainly cause small irregularities to become large shifts in performance and durability - within a very short period of time, perhaps seconds. So if that slide pin was stuck even a little, and keeps one pad from binding against the rotor, it means the other pad will do its work on top of what its already doing. In the process, it gets hotter, and wears much faster. The extra heat will cook any grease left on the slide pin, drying it out and making the situation worse. You can see how this can get out of control in a hurry.

It makes sense that you wouldn't feel any pulling to the side, because the pads are still clamping the rotor with even force from the brake fluid through the pistons, but the calipers are using one pad to do the work of two. The level of work done is the same, but the load is distributed unevenly, and so is the heat, and the wear.

I think this is one reason why track cars use the big brake kits. They deal with heat better in general, and they are built to a higher level of precision required to support track pads' need for ultra even operation. You wouldn't need to worry about slide pins, because there are pistons pushing from both sides. Unless a piston gets stuck, you are immune to such problems we have seen with OEM calipers.

I'm not sure if I was clear -- I had very, very even pad wear for pads on the same side, but the passenger side wore its pads out at least twice as fast.

Hmm. Maybe that stuck slide pin prevented one caliper from doing the same level of work as the other, but clamped enough that you didn't feel a pull. The way the pads work when they get hot, it's more about heat transfer, using 'adherent friction'. This is normal with repeated high speed stops - the pad compound liquifies against the rotor surface, wearing it down more. Over time, that small resistance from the slide pin could have caused both pads in that caliper to wear less, but causing more heat to build on the opposite wheel, doing more of the work. It might have been just enough to push it over the threshold, wearing it uneven over many stops.

From EBC's website:
"Once bedded NDX is capable of 4-5 race events of 30 lap duration in most cases but ALWAYS inspect pads every 30 laps and discard when friction material down to one eighth of an inch or 3mm to avoid fade. In street use the lifetime is very considerable, 20,000 miles an upwards can be expected even driving hard. "

Aaron, to your comment earlier, i have not seen any pitting on my wheels but i do clean them at least once a week.

Here is a passenger side pad after just over 6k HARD miles:
Measured about 3/16" or 5mm at the center.

Thanks for the update. Looks like your pads are wearing fine.

The corrosive dust comes from the Hawk Blue pads, but I've never heard anything bad about the EBC Blue. Entirely different composition, so no worries. I think I will try the EBC blue pads for my next set, or when I decide to take the Riv on track.

How do your rotors look? Still have those heat cracks like you used to have?

The large heat cracks that i had before went away when i got slotted rotors and rid of the 16" wheels. I was just not getting enough air flow and cooling to the brakes.

With the slotted rotors i have now i can see small lines, but i think those are just on the surface. I have no brake jutter or heat spots.
They are wearing very well. still have plenty of time before the slots are gone and i have used these on an entire set of HPS pads and the blue stuff pads.

I think next i want to upgrade to either a stiffer caliper or 13" rotors.

Testing the new Gecko camera mount, I wanted to capture a 3rd-person view of the brakes doing their thing. This is mostly out of pure curiosity, but also to know if any serious problems exist during repeated high speed breaking events. By this I mean braking on public roads from speeds of 70-90 mph down to speeds of 30-50 mph. I generally don't drive much faster, so this is a pretty good test.

I wanted to see how (if) heat builds from one event to the next, and if the rotors were glowing red hot (if discs are hot enough to glow, it's an indicator the brakes aren't being cooled well enough, or the wrong pad/rotor combo is being used. It also could mean the calipers and brake fluid are getting too hot). The following video records 10 decelerations spaced 10-15 secs apart, starting with light braking and working up to higher speeds. Most were as firmly as I can brake without tripping ABS. Events 3-7 and 10 were about as hard as I care to brake on public roads. It's hard to tell in the video, but these decelerations were at a rate of about -20 mph in 2 secs:



Braking events:

1 - warm up from ~35mph
2 - from ~60 mph
3 - from ~70 mph
4 - from ~75 mph
5 - from ~80 mph
6 - from ~80 mph
7 - from ~80 mph
8 - from ~75 mph
9 - from ~55 mph
10 - from ~90 mph

After the test, there was a strong smell of pad compound, but no brake fade up to that point. I feel about 1-2 more stops would be about the limit for this set-up. Still, ten strong stops is more than adequate for a street set-up on a heavy car like the Riv. Also there are no lasting problems as a result of the test, other than the expected pad/rotor wear. No judder, noise, etc.

Overall, I like the F-body mod w/HP Plus pads for the street. Knowing what my brakes are doing helps to build confidence in the set-up. Note the slight glow at the outer edge during harder stops near the end - this is where the outside pad edge is creating focused heat - to be expected, imo - and I'm not that worried about it. A lesser (OEM) pad might be on fire at this point. The verdict: as long as I can get 10 really solid stops with no adverse effects, I'm happy!

Very interesting. Makes me curious how mine look under those conditions.

Matthew, are you still happy with your Blue EBC pads? I'm headed to the track next week, thinking about ordering a pair.

AA wrote:

Matthew, are you still happy with your Blue EBC pads? I'm headed to the track next week, thinking about ordering a pair.

Yes. i still love them and plan on getting them again when these are worn out. Pricy still, but well worth it for the consistency and feel of them compared to the hawks i had before.

Sweet. I just ordered a set from here:

http://www.autoaccessoriesgarage.com/Brakes/EBC-Blue-Stuff-Brake-Pads/_Item/_388200023

$146.51 total, shipped.

PS - EBC has just released a new ORANGE Stuff pad, which is an all-out track pad, high friction, heavy dusting, and not recommended for street use, as it is made to slow your vehicle, not to actually stop it. In a comparison chart they show the Orange Stuff is comparible to the Hawk DTC-30 pad that I used earlier this year. No plans to use either the DTC or Orange pads anytime soon.

EDIT: received my Blue Stuff pads. Overall, I'm impressed with the packaging and finish quality. Can't wait to put them on and test!

New EBC BlueStuff pads went on today. After bedding them in (which was difficult to do in the rain), I did a few high-speed stopping tests. At first, I was a little surprised at the cold performance of these pads. They don't have that strong initial bite like the HP+ or DTC-30 compounds do. A little more force is required, but the friction comes on if you push the pedal. After a while I got used to the slightly harder effort and realized it gave a more precise pedal feel. Multiple decels from high speeds went very smoothly - the added confidence of the BlueStuff compound tends to encourage higher speeds than usual. They should work perfectly for Monday's track runs, and I will probably keep them on for a few weeks to evaluate daily driving. Right now it's looking like they'll remain on the car full time. Thanks to Matthew for the recommendation.

Glad you like them.
I will be ordering my 2nd set in the next month or so.
The pads are holding up well but my rotors are getting thin (already been through a set of HPS pads with them)

If you want to try out my HP+ for comparison, I will mail them to you at no charge if you return them.