Brake Pad Compounds

This page summarizes my experience with various brake pad compouds. It is arranged by manufacturer and then by compound, however I ran different brakes on different cars and in different stages of my development as a driver, hence driving each car differently.

PFC - General

PFC, along with Raybestos, are my currently recommended brake pads. PFC pads often cost somewhat more than Raybestos ones, although not outrageously so. In my experience PFC pads offer good modulation, great bite and a long life, as well as long rotor life. An important characteristic of PFC pads is they are easy to bed and do not require their own transfer layer - see Brake pad bedding for the process I use.

PFC 11

I ran these on the front of my 1997 Miata with stock NA8 brakes.

The 11 compound seems to be more tolerant of aggressive driving than Raybestos ST-43/ST-45 compounds. PFC 11 pads did not chunk or crack.

In terms of bite, PFC 11 is probably somewhere between ST-43 and ST-45. Interestingly enough PFC 11 pads feel equally good with low grip BFG Rival street tires and with Toyo RR compounds, whereas I felt ST-43 to be insufficient for RRs and excessive for Rivals.

The 11 compound requires minimal bedding. I ended up street driving the car for about a week after installing the pads prior to the next track day and by the time I did the first track session the pads were bedded in.

PFC 11 pads did not wear as long as Raybestos ST-43/ST-45 pads but PFC 11 pads stayed consistent throughout their life and did not crack or chunk.

PFC 01

I ran these on the front with Goodwin/949racing big brake kit on my naturally aspirated Miata.

Importantly, there is a difference between the 7752 pad shape that PFC uses on the front and 7112 pad shape that Wilwood pads use. 7752 shape is flat on the bottom (which is toward the front of the car when installed), whereas 7712 is curved and has lower surface area. With the Goodwin v4 or the corresponding 949racing brake kit, the 11~ friction ring is wide enough that the entire brake pad contacts the friction surface. With a V8 Roadsters 11.75" kit however the friction ring is not as wide despite having a larger overall diameter, and 7752 pad shape sticks outside of the friction ring. The inner pad on a corner thus develops a ridge where the friction material is not getting worn off, while the outer pad wears on the spokes connecting the friction surface of the friction ring with the hat which are not meant to be worn down.

I have a good impression of PFC 01 pads. They lasted a long time - probably 20-30+ track days, were predictable and I learned to modulate the brakes with these pads. If not for 7752 being the wrong pad shape for V8 Roadsters friction rings I would continue running PFC 01 brake pads.

PFC 01 were advertised as not needing the careful bedding that Carbotech pads require, but I think PFC 01 do require some bedding. Especially used PFC 01 pads seem to take 1-2 sessions before they bite a rotor with another pad's transfer layer on it - in my case, going from Raybestos ST-43 pads to PFC 01.

PFC 06

I ran these on the rear of my naturally aspirated Miata for experimentation.

PFC 06 seems to be a more aggressive pad than PFC 97. I have adjustable brake bias in the car and with Raybeston ST-42 fronts and PFC 06 rears I had the bias adjustment turned all the way forward and on Summit Point Shenandoah I was locking up the rear tires fist in hard braking zones - going into Old Ram and Corkscrew.

Besides this I have had no complaints about PFC 06. They last a long time, although I don't think not as long as PFC 97. Brake feel is very good. I would try ST-43 front with 06 rear or ST-42 front with 97 rear.

PFC 97

I ran these on the rear of my naturally aspicated Miata with PFC 01 on the tfront.

As advertised by Eric, PFC 97 lasted extremely long on the rear axle. I am confident they were good for over 50 track days.

I do not recall having any complaints about PFC 97s.

Raybestos - General

I believe Raybestos pads are a good choice for intermediate level drivers. They are inexpensive, last a long time if kept in their preferred temperature range, are easy on rotors, require minimal bedding, and Porterfield can put any Raybestos compound on any pad shape they offer. I have a separate page for various Raybestos compounds.

In my experience Raybestos compounds appear to outlast PFC compounds in pad wear. Raybestos compounds seem to be wearing the rotors slower than PFC compounds however Raybestos compounds seem to create small cracks in the rotors much quicker than PFC compounds do.

Raybestos pads will flatten and polish rotors grooved by other brake pad manufacturers (Hawk) or by running brake pads down to backing plates.

In hard driving Raybestos pads do not seem to fare very well. The pads appear to crack and chunk when operated at high temperatures or with high temperature gradients, such as driving aggressively in low ambient temperature. Once the pads begin to crack and chunk the brake pedal becomes soft and spongy, and it becomes necessary to pump the pedal to preset the pads for braking zones.

Porterfield does not recommend using Raybestos pads on the street.

Raybestos ST-43

I ran ST-43s on the front of my naturally aspirated Miata with V8 Roadsters front brake setup, paired with PFC 06 rears. I ran ST-43s after ST-42s.

ST-43s have more braking torque and more aggressive initial bite compared to ST-42s. ST-43s seem to be too aggressive for a non-ABS Miata as I started locking up right front wheel again, sometimes when I did not expect it.

I also ran ST-43s on a naturally aspirated 1.6 Miata. These cars require very little deceleration because they don't achieve high straightaway speeds and can corner quite quickly, and again I felt that ST-43 was too much pad for this car. ST-43s offered rock solid brake pedal and good deceleration rates, however I worried about overslowing the car in the braking zones.

I recommended ST-43s to several people while I was running ST-42s (but thought I was running ST-43s). The feedback I have heard from drivers running NC Miatas which are heavier than NA/NB Miatas and have ABS was universally positive. ST-43s may be a good fit for cars above 2500 lbs and cars with ABS based on this data.

Raybestos ST-42

I ran these on the front of my naturally aspirated Miata with V8 Roadsters front brake setup, paired with PFC 06 rears.

ST-42 have very smooth engagement and are very controllable in a non-ABS car. I have been braking later and more aggressively on ST-42s than on any previous pad I had run, flat spotting fewer tires in the process. ST-42s do taper in Wilwood Dynalite calipers but the taper is manageable.

ST-42s do not seem to require bedding. I slapped them on friction rings that had a transfer layer from PFC 01s and ST-42s started working immediately.

The only unresolved issue I have with ST-42s is an appropriate rear pad to match ST-42s on the front. PFC 06 is too aggressive of a rear pad for ST-42 fronts; at Summit Point Shenandoah I was locking up the rear tires in low speed hard braking zones. PFC 97 might work well with ST-42s, and I also want to try ST-42 rear.

Porterfield R4

I ran these on the front of my 97 Miata. Rear pads were Carbotech XP8.

R4s seemed to have a lower initial bite and a lower friction level compared to ST-43s and ST-45s. My initial impression was that R4s and ST-43/45s were comparable; however, after going from R4s to ST-43s (after R4s were worn out) I can definitely say ST-43s have much more initial bite - they were definitely very grabby coming from R4s - and used less pedal effort throughout the stop.

However, it appears that R4 has higher heat resistance than ST-43s definitely and ST-45s possibly. On the 97 Miata Raybestos pads cracked and crumbled over time, and produced a progressively softer pedal. The soft pedal feel was especially apparent with ST-43s. Pedal feel with R4s was much more consistent, despite requiring a higher pedal effort to attain the same deceleration. Unlike Raybestos pads, R4s showed minimal cracking throughout their life up to the point when they were removed from the car with barely any friction material left.

R4s were time consuming to bed. It took two track sessions at speed to get the pads completely bedded. Once the pads got hot in the first session, the car had seriously compromised braking performance for the remainder of the session, whereas Raybestos compounds do not fall off that much during bedding. And then the pads turned out to not be bedded in the next session. Once bedded the pads work OK.

Bedding R4s on the street is impossible.

Prior to bedding, street friction level was quite low. Certainly worse than unbedded ST-43s, close to unbedded ST-45s but still less. Once bedded, street friction level was decent. ST-43s did better in street driving than R4s, but R4s are on par or slightly better than ST-45s.

A Porterfield sales rep agreed that R4 has a lower initial bite and a lower friction level than ST-43, and recommended PFC 11 as a pad to try to combine the heat resistance of R4 with the bite of ST-43.

Carbotech - General

Many people seem to love Carbotech (now G-Loc) brake pads. Personally I have not been successful in bedding them in. My first set - of XP12 fronts and rears - I apparently glazed early in their life, and as a result had no brake modulation for something like 2 years of track driving. The next set I got was XP10 in the front and XP8 in the rear; they lasted a few months (10x wear rate of XP12/XP12). I tried pre-bedded Carbotech pads which did not seem to last any longer but were even more expensive. In my experience I did not find Carbotechs to be easier to modulate than properly matched PFC or Raybestos pads, and since "legendary modulation" is Carbotech's primary selling point I see no reason to use them.

Carbotech XP12

I ran either XP12 front and rear or XP12 front with XP10 rear with a Goodwin v4/949racing big brake kit on my naturally aspirated Miata.

The pads offered virtually no modulation; coupled with Hankook C30 compound tires, front wheel lockup was extremely easy to achieve and was constantly plaguing me. Every single tire I tossed was ruined by flat spots rather than worn out. Lack of braking modulation also set back my personal development as a driver - it took me years after I switched to PFC and Nitto tires to start braking as late as cars comparable to me were braking.

The first set of Carbotech pads also lasted me about two years. When I mentioned this to a Carbotech customer service rep he informed me that I likely glazed the pads when I was bedding them.

Carbotech XP10/XP8

For my second Carbotech set, still on my naturally aspirated Miata, I went with the recommended Spec Miata setup, XP10 in the front and XP8 in the rear. XP10/XP8 combo did not last me anywhere near as long as the first XP12 set. I do not recall what I thought of brake modulation but I was definitely of the opinion that I was still not bedding the pads in properly, and I started getting pre-bedded pads from Carbotech (which further increased their cost). After two sets of Carbotech pads I asked Eric Wong of brakeswap.com for a recommendation and he recommended PFC 01 front pads and PFC 97 rear pads.

I would like to note here that when Carbotech says their pads require their own transfer layer on the rotor, they mean it. I tried putting a Carbotech pad on a rotor that was used and the result was a brake system that felt like all season tires on ice - "skaty". It was not a pleasant feeling at all.

Hawk - General

The major selling point of Hawk pads is that they make pads for just about every vehicle ever produced. The chances of there being a Hawk brake pad for less commonly tracked cars are much higher compared to other vendors. Hawk pads are also often cheaper than their competitors, plus Hawk has a great NASA contingency program.

On the other side, just because Hawk makes pads in a particular shape does not mean they make them with all of their compounds, hence compound options can be limited for less popular vehicles. Hawk pads from HPS to DTC-60 at least tend to groove rotors which helps with neither rotor life nor brake pedal feel. DTC-70 compound, Hawk's top of the line brake pad, can be significantly more expensive than DTC-60 compound. It is my impression that Hawk pads do not last as long as PFC or Raybestos pads, and have a higher incidence of outright failure.

I avoid running Hawk pads on the front axle, however in budget-minded applications they tend to do OK on the rear axle which generally has much stricter demands.

Hawk DTC-60

I ran DTC-60 on the front of my EF Civic with a ZC swap. The experience did not last long because the friction material separated from the backing plate in the first session while I was bedding the brakes. Maybe I run the first session too hard for Hawk compounds, maybe the stock brake system is just not adequate for track use, maybe I had a sticking caliper (the rotor cracked on the side where the pad backing plate separated). What I do know is that I run other brake pads harder and they do not give me any problems.

I ran DTC-60 on the rear of an NA8 Miata with ST-43 pads on the front. This combination was somewhat too much rear biased, as evidenced in hard braking zones over crests, but was acceptable enough given that I got the DTC-60s for free.

Hawk HP+

I ran these on the front of my EF Civic with a ZC swap. The car had drum rear brakes.

Despite being advertised as a track pad, HP+ faded in 15-20 minutes of hard track driving, and they were used on a rather light car (2200 lbs race weight). The pads also wore out quickly.

I would run EBC Yellowstuff in preference to Hawk HP+. Yellowstuff seem to be more heat resistent and they seem to last a bit longer too.

Hawk HPS

I ran these on my DA Integra with a GSR swap, front and rear.

One of the front calipers was sticking which destroyed the pads in it in about a day. The other side fared better.

I was under the impression the car had anti-lock brakes because I was not able to lock up the tires despite putting a lot of effort into the brake pedal. As the car started locking up tires with other brake pads, I now think that HPS were either overheating or flexing to such an extent that they ceased to provide full braking torque.

HPS pads to ok in the rear, especially on stock brake configurations (which my Integra was) that are heavily front-biased.

HPS pads groove the rotors they are used with. I do not have enough track time on these pads to say how long the rotors last but the grooves obviously indicate loss of material.

Cobalt XR3/XR5

I ran one set of these on my NB Miata with Wilwood V8Roadsters/Goodwin/949racing big brake setup. They had the shortest life of any brake pad I had on that car in recent memory, perhaps equaling Ferodo DS2500 in longevity. I believe they lasted on the order of 3-4 weekends when I usually go 20+ weekends on front pads.

From what I remember the bite, friction coefficient and modulation were good, but since Cobalt pads cost in the same range as their competitors while lasting 5-10 times less I did not buy any more of them.

Ferodo DS2500

I had a set of DS2500 pads on the front and rear of my naturally aspirated Miata when I started doing track days.

DS2500 are advertised as maintaining constant coefficient of friction at any temperature. In my experience this was true - the brakes on the car felt great the entire time I had Ferodo pads on it. However, the trade-off was very short pad life. The pads only lasted me several weekends and I don't think I was as aggressive on the brakes back then as I have been more recently.

EBC Yellowstuff

I ran these on the front of my DA Integra with a GSR swap, paired with Hawk HPS in the rear.

Yellowstuff pads did well in the friction department, offering consistent braking performance throughout the 2 days I had them. The downside of the pads is they lasted all of 2 days.

I got my Yellowstuff pads in Pep Boys the day before the event and for an "emergency" brake pad, Yellowstuffs do quite well.

Duralast Gold

I ran these on the front of my EF Civic with a ZC swap. The car had drum rear brakes.

Duralast Gold was an emergency purchase after I wore out the previous pads at Watkins Glen. The pads lasted 10-12 minutes of hard driving at Watkins Glen, which is a brake-heavy track. After several sessions the backing plates on the pads were bent due to piston pressure and the friction material cracked as a result. At this point the pads lost much of their ability to decelerate the car.

Duralast Silver

I ran these on the front of my EF Civic with a ZC swap. The car had drum rear brakes.

I put Silvers on as "emergency emergency" pad after Duralast Gold pads I had on the car previously bent under piston pressure.

The Silver pads were fading after several hard brake applications. They are not at all suitable for hard track driving. I got several sessions out of the Silver pads by backing off braking intensity.