Centric Parts:
centricparts.com
(626) 961-5775
Hawk Performance:
hawkperformance.com
(800) 542-0972
Mazda:
mazdausa.com
Race Technology:
race-technology.com
Tire Rack:
tirerack.com
(888) 541-1777
Photography by Per Schroeder
Going skydiving? You’ll need a parachute. After all, it should make leaping from that airplane a bit more survivable.
Of course, not all parachutes are the same, and there’s more to them than different colors. Parachutes come in a variety of airfoil shapes and sizes, each one suited to a particular jumper and situation. While they’re all designed to serve the same basic purpose, there are subtle differences in the huge range of offerings.
You can think of brake pads in a similar way. Although there are countless varieties of pads available today, they all do the same thing: create friction to slow a car. Of course, the faster you go on track, the more important it becomes to have adequate stopping power.
High-performance brake pads are a crucial component for a car that sees open track time or race use. Not only are these top-tier pads more resistant to fade, but they can also have a higher coefficient of friction for quicker stops. Of course, that improved pad friction will only help if the tires are good enough to take advantage of the increased brake torque.
But what about autocross use? Are high-performance pads an advantage when battling the cones? While the brakes usually don’t get smoking hot during a 60-second autocross run, they can still see elevated temperatures, especially if there’s a co-driver adding a second dose of abuse.
More importantly, most of us autocross on sticker-than-stock tires. Can increases in brake pad performance help those grippy tires yield faster times?
To compare these theories against the stopwatch, we pressed our 2010 Mazda MX-5 project car back into service. To see how brake pads impact autocross performance, we tested four different brake compounds: the OE Mazda pad, the street-performance Hawk HPS, the track-worthy Hawk HP Plus and the race-ready Hawk DTC-60.
Our Mazda’s KW coil-over suspension and fat Dunlop Direzza Sport Z1 Star Spec tires make it a great platform for evaluating brake pads. The car is easy to drive, and we’ve found the Dunlops to be very consistent throughout the day and over a wide range of temperatures.
Tire Rack’s John Rogers and Chris Harvey served as our test pilots for this exercise. They’ve logged thousands of laps on Tire Rack’s own test course—which would again serve as our test lab—and have a considerable amount of seat time in the MX-5 project. A Race Technology DL1 data logger handled the data acquisition for the track work, while a Vericom VC2000 recorded the 60-to-zero stopping distances.
We tested each of the four pad compounds on a separate set of brand-new Centric rotors. By testing each pad with fresh rotors, we eliminated the possibility of contamination between samples.
Each set of pads was bedded in using the manufacturer’s recommended procedure. This included several stops from speed plus an appropriate cooldown period between sessions. The pads and rotors were then removed from the car and set aside until our day of testing.
We started with the stock Mazda pads and then, in order, went on to the HPS, HP Plus and DTC-60 compounds. We finished off the day by retesting the original pads; this is a great way to make sure the surface and conditions have remained consistent.
Each set of pads also went through the same test sequence, starting with four two-lap runs. Immediately after logging those laps, we did five 60-to-zero stops on a section of level asphalt.
The pads that originally came on the MX-5 feature a ceramic-based compound and are considerably better than the stock pieces of yore. Today’s ceramic material yields both good pedal feel and fade resistance without the typical increase in noise or dust.
Our drivers felt that the initial bite and stopping power of the OE pads were better matched to original tires than the high-grip Dunlops, however. “The OE pad requires moderate to heavy pedal pressure to get the braking effort needed to haul the car down from speed,” John noted.
Chris backed that up with a similar observation: “The Mazda pads exhibited the least initial bite and required the most effort to reduce speed throughout the brake application.” The bite, or lack thereof, indicated a lower-than-optimal coefficient of friction for our autocross application.
However, the stock pads didn’t have any real bad habits. Chris thought the modulation and pedal feel were not an issue at the limit. He also didn’t encounter any noticeable fade. “They were smooth, quiet and clean, as they went about their business without any drama,” he added.
John summed up the stock pad’s performance with some surprisingly kind words: “These pads provide moderate initial bite and have a very linear feel. The braking effort changes up and down directly in relation to pedal effort. Overall these pads have good brake feel, they just require lots of leg effort for peak deceleration.”
Hawk Performance HPS pads are seen as a step up the performance ladder from the stock pieces. These performance-minded pads are built from a carbon-based friction material, and according to the manufacturer they offer more stopping power with minimal increases in noise and dusting. They also have a higher heat range than most OE pads, making them suitable for high-performance street, autocross and light track use.
Both of our drivers noticed that the HPS pads delivered a nice increase in initial bite and stopping power over the OE pads. Chris applauded the HPS’s behavior: “These traits inspire driver confidence when pushing the car to the extremes of the performance envelope.” He found that the HPS’s quicker reaction time and stronger braking power better matched the modified MX-5. “The strong initial bite and flat brake torque curve is like a friendly handshake with the tires’ contact patch, allowing the driver to feel the limit without going unexpectedly beyond,” he noted.
John added that the HPS pads are also easier on the driver. “These take much less physical work on behalf of the driver to utilize all of their performance,” he noted.
The Hawk Performance HP Plus is a similar to its “little” brother in that it’s meant to be a multipurpose pad. However, the HP Plus favors higher heat capability at the expense of increased noise, rotor wear and dust. According to Hawk, the HP Plus is designed to be a track-capable pad that can manage the drive home. It’s also intended for the serious street and autocross enthusiast.
Compared to the HPS, the HP Plus delivered a significant jump in initial bite and considerably more stopping power. However, this newfound braking performance came with an unexpected result: Our drivers slowed too much and misjudged their braking points.
The excessive slowing was compounded by brake-torque ramp-up—as the car dove deeper into the braking zone, more braking power was generated without any increase in pedal pressure. “This trait initially led to over-slowing for the turn-in point, but was easy to adapt to,” Chris noted.
“This pad has a somewhat rising rate of friction,” John explained. “The braking force climbs gently even with no additional pedal pressure application. This instills confidence, as the braking effort is reassuring.”
Overall, both drivers enjoyed the HP Plus. Braking inputs required a fine touch and became more of a thought process than a muscular action, Chris noted. He added that the additional power was very reassuring but a bit abrupt for this application. While many drivers could easily adapt, this pad may be better suited to a heavier vehicle or higher-speed applications, he explained.
“Without being completely calibrated to the pedal feel, it’s easy to slow down too much at the end of the slalom and into the final turn with the HP Plus,” John said. “However, simply think the word ‘brake’ and the car slows. You can work the pedal with your toes and ankle, not the big muscles of your leg, allowing you to really fine-tune the brake pedal pressure.
The DTC-60 is one of Hawk’s many race-specific compounds, products that have no business being used on a street-driven car. For one, these pads are only meant to work between 400 and 1600 degrees Fahrenheit. Until the pads reach that temperature range, they’re tough on rotors and create copious amounts of noise and dust. They’re simply designed to cope with the rigors of track use.
Despite its hardcore nature, the DTC-60 worked surprisingly well on the test course. “As a true race pad, I expected a big upward swing in initial bite and stopping power as the pad warmed up,” Chris explained. “This was not the case, as the pad responded strongly to the initial pedal application and had stopping power to spare, even when cold.”
Two negative traits did crop up, however. The initial bite was strong enough to momentarily lock the front tires until weight transfer took place. This somewhat delayed full braking, as the ABS computer struggled to keep up with the instantaneous brake force. The pad’s peak braking g-loads suffered, and the drivers could feel the ABS system cycling pressure on and off.
The DTC-60 brake pad also lacked feel and feedback through the pedal. “The friendly handshake of the HPS pad had turned into an iron fist,” Chris noted. “The pedal has a somewhat dead feel,” John added. “I find it difficult to read what is going on in the tires’ contact patch. Successive laps created some familiarity with the DTC-60 as I learned how to gently squeeze the pedal rather than jab at it.”
The funny thing about brakes is that the less you use them, the faster you can lap an autocross course. The secret to a quick run is knowing exactly when and how much to brake, then avoiding the pedal entirely the rest of the time.
While our drivers noticed obvious differences in the feel of the brake pads, the data showed otherwise. There were no significant objective differences between any of the brake pads in terms of the lap times, peak stopping forces, or stopping distances. This makes sense, as we didn’t change the biggest factor in braking performance: the tires.
However, good pedal feel and consistency can definitely help driver comfort—which can then translate to confidence and better performance. Our recommendation is to shop for autocross pads based on feel rather than concept. And if you want to crib from our notes, our drivers loved both the HPS and HP Plus pads—we’ll be running the HPS in the future.
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I'm no racer, but one of our more consistent local winners uses the cheapest organic pads he can find for his Camaro in the cones. When he hauls it to a stop at the end, you can see puffs of orange flames coming off the clouds of dust from the pads. His rationale is that the short runs don't get them hot enough to be an issue, and (since he drives it on the street) the organic pads don't shred the rotors. Any glazing he gets during the few runs he does are easily scrubbed away on the trip home and he's left with normal street braking again.
That's just an anecdote from one racer, but that was his story and he's sticking to it.
I use craptastical ordinary pads I the Datsun I road race. Note I have Z car brakes on a 1600lb car so heat isn't an issue. I'm also not giving up and performance to people using high end race pads. When I raced a showroom stock Miata I tried both the Hawk Pads and the stock Mazda pads and found the same thing the test did, the Hawk pads had better feel but the more aggressive pad also went through rotors faster. I went to the stock pads for this reason. Basically I don't think there is a wrong answer here.
Oh hi, Per Schroeder.
Very interesting. I have tried quite a few pads on the FiST and found much of the same to be true. Track pads worked great on the track, but for autocross they were lightswitches with no modulation at all. Some national-level folks actually prefer the OEM pads from Ford, but even at that, there are two different part #s available based on year and one is better than the other.
My WAG is grippier pads would only be a benefit with equally grippy tires. Otherwise, you are just trying to not lock up or engage the ABS as much?
And I'm also surprised to see a post by Per?
I'm with Curtis on this one, although the camaro with race brakes that runs locally does look cool in pictures with the glowing rotors on course.
Per? Are you ...back? Like for real?
I prefer R4S versus R4E for autocrossing, but once you get to higher speeds and longer runs when temperatures can be reached and held, my preference shifts to R4E.
Mezzanine said:Per? Are you ...back? Like for real?
Holy crap I didn't even catch that.
Mezzanine said:Per? Are you ...back? Like for real?
The article is from the February 2011 issue, they posted it under his name since he wrote it.
So no, he's not back, but he has been known to lurk here.
Stefan (Forum Supporter) said:Mezzanine said:Per? Are you ...back? Like for real?
The article is from the February 2011 issue, they posted it under his name since he wrote it.
So no, he's not back, but he has been known to lurk here.
Correct. But if you're in the market for Porsche parts, Per has been at Stoddard Porsche outside Cleveland ever since he and Kim moved back north with their kiddos. Give him/them a call!
Margie
As someone who has autocrossed a prepped NC Miata I can absolutely confirm that better brakes make you faster. The first time I drove my (now former) car I blew through the outside of a few corners. The car simply didn't have the bite in the pads to slow down. So I had to adjust and brake earlier.
If I'm braking earlier, I'm off the gas and not going as fast as I theoretically could be.
So when I bought the car it for high end rotors and HPS 5.0 pads which were VASTLY better than the OEM pads it had come with. (This was even more noticeable when I went to Hoosiers, even the Hawk pads weren't enough to get into ABS then.)
Beetlejuice!
A guy who used to kick ass locally in a B/Street AP1 S2000 was not only running stock brakes, they were the original pads that had left the factory with the car 75,000 miles earlier. I would take that as BS, but the guy was not the type to tell tall tales.
I like the feel of HPS/R4S for autox. Sure, they may not physically stop faster, but the feel is different. Since most of what we do is by feel (where's that maximum grip without push, when can I get the back on the throttle without oversteer etc) that can make the difference.
Just my non-professional, 12 year experience. I've run Tubey stock pads, stock upgraded pads/rotors (size) and blues. The stock pads just feel.... lack luster after having good pads on it.
In reply to KyAllroad (Jeremy) (Forum Supporter) :
Interesting, I had the opposite experience in my 2006 Sport that I prepped for STR. I never felt the need to upgrade the pads. They had great bite and the ABS programming seemed right on for my driving style. I definitely had to stand on the pedal but I always got what I needed in terms of bite and braking.
On a Honda 96 Civic 3 door with 99-00 civic Si brakes all around the HP+ did not want to stop the car first time around on freezing ish mornings or after awhile without using the brakes if it was that cold. Its was pretty spooky a couple times... The HPS that went on next would work fine when freezing- Which seems about right in line with what Hawk describes as the general use scenario for the respective pads at the bottom side of the heat zone.
I run Hawk HP+ for stage rally, but find that when i rallycross the first several braking zones on course I have no bite to speak of until they warm up. I usually will drag the brakes from grid to start to try to get some heat in them, but even that doesn't work well. Now I switch back to HPS for rallycross.
I admit to running Hawk BLues on the Tib through winter. I know, I am a terrible and lazy person. but down to freezing temps they were fine. below freezing the first stop wasn't as crisp, but after the first one they worked. Sure, there's rotor wear but that is expected IMO on a pad this aggressive.
I'm another oem nc pad user for STR. I've not seen the "need to bleed the speed" on course, and where the oem pads fail it. In fact, for autocross, I can only see upgrading brakes so you don't blow the stop box (I've seen many do this locally, but my nc does fine.)
I bought my last dedicatd autocross car from a hard parker. The owner managed to find a set of brake pads that faded after three autocross 55-25mph brake zones. As I got faster, I started getting random soft pedals that I couldn't figure out. I spent a bunch of time chasing down bubbles and brake fluid compounds. Someone finally suggested a different pad and it solved all my problems.
Unless you have awful parts that just arent up to the task, its all more about feel and driver comfort, especially on an ABS car.
As an aside, one of the most prevalent mistakes I see in newer and even medium experience autocrossers is being so aggressive on the brakes they totally screw up their corner entry (which totally screws the whole corner). Less touchy brakes, even if you get less raw stopping power from them, may actually be advantageous to prevent this.
irish44j (Forum Supporter) said:I run Hawk HP+ for stage rally, but find that when i rallycross the first several braking zones on course I have no bite to speak of until they warm up. I usually will drag the brakes from grid to start to try to get some heat in them, but even that doesn't work well. Now I switch back to HPS for rallycross.
Interesting. According to Hawk, the HP+ has more friction than HPS at all temperatures:
Great compilation of data, imbedded in a really useful article.
The NA and NB Miatas that compete in E Street have some unique requirements.
Due to the significant front bias engineered into the platform, many of us will try to use a different pad front to rear to try to shift some of the brake bias to the rear.
My NB1 had been set up in such a manner when I bought it. The brake bias is probably as good as it could be (still locks up the front first), but it's got too firm of a pedal (my usual preference is a firm pedal) that makes it hard to modulate. I'm hoping fresh fluid will make a difference.
ProDarwin said:irish44j (Forum Supporter) said:I run Hawk HP+ for stage rally, but find that when i rallycross the first several braking zones on course I have no bite to speak of until they warm up. I usually will drag the brakes from grid to start to try to get some heat in them, but even that doesn't work well. Now I switch back to HPS for rallycross.
Interesting. According to Hawk, the HP+ has more friction than HPS at all temperatures:
My comment on this comment is... that this data appears to actually begin at 100F. Starting line temps at a rallycross could easily be significantly colder, and that's likely the issue.
My Solo days are a long time ago, but slaloms are just races in miniature, so....
There are two things to seek/worry about - how quickly do the pads grip, and will you generate enough heat in a solo event to have to worry about fade.
The answers are - yes, the initial grip of some pads sucks. That was the case with the stock GM pads on my Solstice. If you lose 1/3 of a second every time you apply the brakes in a solo event, I think you just lost to someone with better pads. I switched that car to some EBC Red Stuff that gave pretty much instant grip. On the fade, I do believe that it is a concern especially for higher speed open courses with heavier cars. While obviously not as demanding as being on a race track, you want something that not only gives instant grip, but also a compound that doesn't fade on you in the last run of the day. A full race compound will be overkill but a steer performance compound should work well.
I have some Porterfield R4S that do a good on on another car.
ojannen said:I bought my last dedicatd autocross car from a hard parker. The owner managed to find a set of brake pads that faded after three autocross 55-25mph brake zones. As I got faster, I started getting random soft pedals that I couldn't figure out. I spent a bunch of time chasing down bubbles and brake fluid compounds. Someone finally suggested a different pad and it solved all my problems.
He probably put on some ultra-low-dust pads so he wouldn't need to wipe the wheels off again when he arrived at the car show.
Who moves TO Cleveland willingly?
Following up on my previous post. Fresh fluid helped with the modulation on my ES Miata. Not great, but improved, and the balance front to rear seems better also.
I never liked the brakes on my 04 Ralliart wagon until I put some Stoptech Sports on the front. It would stop okay with regular parts store ceramics, but the modulation really wasn't good. I know the Stoptech is not a highly regarded pad, but they really transformed the car. They stop better and the modulation is great.
One factor with the Ralliart is that there's not a lot of options if you want to have the same pads on both front and rear. It's a bigger concern than when it was when only a commuter car. I found out that it's a competent autocross car, so I'm going to occasionally compete with it instead of the Miata.
I want to do new pads all around, but there's not a lot of choices for the street and autocross category available for both axles.
In reply to spitfirebill :
Because Northeast Ohio is a great place to raise a family and with all the garbage we have going on now we have some of the best healthcare facilities in the world. You should check things out before you open mouth and insert foot!
In reply to Mustang50 :
I did. It didn't change my mind.
So as expected, the pads made approximately no difference to overall performance. People often upgrade brake pads and discs and calipers for the wrong reasons - they want a pedal that feels sharper or is more sensitive, which is a more of a MC/caliper bore matching issue (and in the big picture, a comfort issue that you can work around with changes to driving technique), when there are really only two good reasons to change these things:
1: You're having trouble generating enough braking force to lock up the wheels/activate ABS
2: You're having brake fade or maintenance issues due to heat.
In autocross we can nearly disregard the possibility of #2 due to the length of an autocross run, you'd need a massive-but-powerful car on bargain-bin pads to have heat issues. #1 is a very uncommon issue especially with stock wheel setups, but might happen with wheel & tire upgrades.
So generally, you can't address a real braking problem in autocross by changing pads, but you can sure give yourself some pads that are harder to control due to very high friction compounds and being below a decent operating temp most of the time, and will eat your rotors a lot faster as a bonus!
In reply to spitfirebill :
Your loss, chew vigorously!
This rolled back through again on the forum, and since I have another car since I last read it, I thought I would refresh myself. Reading the comments, I found that I had also replied a couple of times.
Here's the update on my Miata. As I had commented in January, fresh fluid did help a bit.
What made a bigger difference is that I'm now re-bedding the brakes on my way to the events. I do three or four hard stops from 50 to 60 mph down to about 10 mph, then drive normally to the event. Pedal feel and modulation is much better since I started doing that.
The new car, a 2008 civic coupe with a 1.8/5 speed will be my daily driver and bad weather/backup auto cross car. It will get a set of Hawk HPS pads and some plain Centric or Brembo rotors soon.
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