Above all else, there are two main factors to consider when choosing high performance brake pads for your car - their coefficient of friction and operating temperature range. Put simply, the coefficient of friction is the frictional resistance (drag) of the pad against the rotor - which is very important when you want to rapidly slow the rotor (and therefore the car). The higher this number is, the greater the pads' ability to grip against the rotor. As a guide, a good pad usually has a co-efficient of friction of around 0.45-0.5 when it's working at the temperature where it's most suited.
Brake Pad Bedding In
Brake pads and rotors should always be initially bedded to condition the pads and rotor surfaces for racing use. This "bedding in" procedure will result in greater performance, longer wear, and less likelihood of rotors cracking due to thermal shock. To bed in brake pads, start by pumping your brakes at a very low speed to assure proper brake system operation. In a safe location, make a series of progressively harder stops from moderate speeds until some brake fade is experienced. Allow brakes to cool while driving at moderate speeds, avoiding use of the brakes. The brake pads should now be properly bedded in. Pre-Bedded Pads Some manufacturers (such as Wilwood) have a bedding in service that is performed on a computerized dynamometer to ensure a consistent bed across each pad set. This is generally only available on extra-high performance brake pads, where "ready-to-race" pads are valuable during an event.
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Having a set of pads with the correct temperature range is also critical. But it's very important to select a pad that has both the right minimum and maximum temperature ratings. For example, there's no point in fitting pads on a street car that will only really start working at over 100 degrees C - 'cos what happens when you pull out from your house and need to stand on the (cold) brakes? They don't work very well. Further to this, it's a good idea to use fairly low temperature pads on a road car or else excessive pad wear, noise and abnormal rotor wear may result. On the racetrack, however, brake temps of around 600 degrees C (often more) are generated at the rotor - and it's imperative that the pad can maintain effectiveness under such demanding conditions.Otherwise, a major loss of braking power will result as the pad "glazes" and simply slides over the disc rather than biting against it (which isn't what you want at high speeds!).
But which braking temperatures are particular to your car? There are three ways to find out.
You can measure braking temps with a brake temperature pyrometer, stick-on caliper temperature strips, or (most simply and cheaply) some temperature sensitive paint. There are three different paint colours available:
Green - Turns to White at 430?C.
Orange - Turns to Yellow at 560?C.
Red - Turns to White at 610?C.
Watching to see if any of these paints discolour on the edge of your brake rotor will give you an indication of your braking temps.
But now that we know the fundamentals of choosing pads, it's important to bear in mind that "experimentation is often necessary to determine the optimal brake pads for an application". Variables such as caliper size, rotor type, rotor operating temperature, operating duration, and driving habits all affect brake pad performance. So, unfortunately, it's often going to be a case of "suck it and see.. ".
Our Selection of Pads
Here's AutoSpeed's selection of both the finest and most cost-effective hi-po street usable/sprint pads on the market...
Hawk Pads
The well known US brake pad manufacturer - Hawk - is a division of Wellman Friction Products Co and has come to "utilise world class technology to develop and manufacture superior disc brakes for the automotive/racing industry". Here is its more mainstream range, starting off with a couple of fairly extreme ones:
Blue MT4 - A high torque pad designed specifically for circle track cars under 2800lb (1270kg). Excellent pad and rotor wear rate. Good brake modulation characteristics similar to the higher level HT8. Temperature range between 200-640 degrees C.
Blue 9012 - The Blue 9012 is a medium-high torque brake compound. It's a proven reliable performer with a wide temperature range and low pad and rotor wear rate. Also has good brake modulation characteristics. Recommended for road racing and rally applications, where low to mid range temperature effectiveness is required (37-530 degrees C).
Black - Medium torque compound for grass roots racing. Designed to be a good, all-purpose, low cost racing pad. Recommended for dirt circle track, dune buggy, and light duty road racing applications. Temperature range 92-480 degrees C.
HP Plus - A high torque street material plus it's raceworthy. Very high torque and rotor friendly for the serious street driver. Can also be used for club events and driving schools. An excellent multipurpose pad that's good for up to around 450 degrees C.
HP S - Another high performance street material, slightly less hi-po oriented than the HP Plus. Extremely low dust, high friction, rotor friendly, silent running brake pad. Improved performance over OE pads and effective up to around 350 degrees C.
AP Racing
As the major manufacturer of brake systems for competition and high performance vehicles, AP Racing is in a position to evaluate brake pad performance both on dynamometer test beds and vehicles. The most successful high performance / competition pads over the last 5 years have undoubtedly been the Carbon Metallic® range produced by Performance Friction. Their very high friction level, low wear and almost fade free performance have made them the No1 choice in nearly all areas. AP Racing is the principle European importer / distributor of Performance Friction Brake pads and is able to offer an extensive range.
Pagid
Pagid is the pad of choice for many race teams, including various BMW Motorsports teams. Numerous compounds are available, so we recommend that you contact your local distributor for availability.
RS 4-2-1 Black - A high performance compound with good fading characteristics and high cold friction. The most comfortable medium friction sport compound. Street-legal, rotor friendly and OE on various Ferraris and Corvettes.
RS 4-2 Blue - A medium friction racing compound with good cold friction and fading resistance up to 500 degrees C. The 4-2 compound has a reasonable rotor wear rate also. It has very good modulation and is a Classic Rally compound and is also used for small open wheelers (F3, F-Renault, club racing etc).
RS 4-4 Orange - This compound has very good fade resistance and a higher average friction value than the RS 4-2. It is rotor friendly with a very foreseeable non-aggressive friction behavior (stable torque). It's an excellent rear compound for Touring Car applications in combination with RS 14 front pads. Its main application is Porsche 911 racing, but it is also used on either short track or long distance.
RS9 Yellow - This is a classic endurance compound with superior pad and disc wear up to 450 degrees C. It has a medium friction value suitable for booster equipped systems with good dimensions and reasonable cooling. This compound is also an excellent solution for over-braking (locking up). Used together with rear axles using RS 4-2, RS 4-2-1, or RS 4-4 on the front. RS9 can also be used as a sport compound for street applications.
Mintex
In addition to Mintex's standard aftermarket materials, the company also offers a specialised range called the C-Tech racing pads. This family of materials has been developed from Mintex's involvement in motorsport and covers a spectrum of vehicles from hot hatches to full race machines.
Mintex M1144 - The M1144 material is mainly used for fast road use and is primarily targeted at hot hatch drivers - for fast road use as well as light competition such as karting, hill climb and single seater racing cars. One of the main characteristics of this material is the ability to work from cold, which gives the user the confidence of a standard material on the first application of the brakes. The benefit of M1144 is experienced as the temperature within the brakes starts to increase. M1144 will remain stable and consistent through to 450 degrees C, where a standard material at this temperature will most certainly start to fade.
The other three materials M1155, M1166 and M1177 are specifically for circuit and rally competition use. Under no circumstances should they be used for normal road applications. Applications such as Group A and N rally cars and circuit saloons best suit these compounds. M1155 has a very high friction level that remains consistent to a maximum operating temperature of 550-600c.
All the applications covered by these compounds can be found in the latest online C-Tech catalogue.
QFM
QFM (Queensland Friction Materials Pty Ltd) offers several types of hi-po pads. The main philosophy behind these pads is hi performance at a low price.
One of the most popular types of QFMs is the comp series:
Comp 02 - This entry level Comp series pad gives good overall performance, very little wear on rotors, best suited to light sports or performance cars.
Comp 03/06 - Both give very good performance with a low wear rate. They're very good for heavy high performance road cars and highly suitable for rally cars. Excellent low temperature performance (0.38 coefficient of friction) with a temperature range of up to 700 degrees C. The Comp 06 differs by having a cold coefficient of friction of 0.40 and a hot coefficient of 0.47.
Comp 9 - This is a very high friction compound with a low wear rate. It is a highly suitable race or rally compound. Even better low temperature co-efficient and improved high temperature performance that extends 50 degrees further (to 750 degrees C).
Comp 15 - The Comp 15 has a low temperature coefficient of drag of 0.45, a high temp coefficient of 0.49 and a temp range from 0-770 degrees, making it a highly suitable race compound.
RB74 - This is a pad that's been well proven in sprint races under cars such as HSVs, WRXs and other turbo cars. Creating little wear, it gives a coef of 0.43 at up to 500 degrees C. It also works well on the street, with very good low temperature effectiveness.
RB62 - This pad is ideally used on the back of cars fitted with RB74s at the nose. It's another organic/metallic pad that gives a co-efficient of friction of 0.41 at up to 450 degrees C. It's very similar to the RB74, except it is a bit "lighter" in its compound.
Ferodo
Ferodo are one of the largest pad manufacturers in Australia and sells a large variety of OE replacement pads.
Zero - The Zero is a material using a non-asbestos basis of steel filaments spaced in a random dispersion. It contains a blend of selected friction modifiers together with a specially developed impregnant. It gives a general purpose coefficient of friction, and can be used on a wide range of saloon and commercial vehicles. It has a maximum continuous operating temperature of 225 degrees C, with a maximum tolerable temperature of 500 degrees. Its listed maximum rubbing speed is 24 metres per second.
Metal - This pad has a medium-high friction level, good fade resistance, excellent resistance to wear and is "extremely kind to brake disc surfaces". It is, though, harsher than the Ferodo Zero. It also has a maximum continuous temperature of 225 degrees C, an outright maximum of 550 degrees and a max rubbing speed of 24 metres per second. It's available to suit a wide range of applications from spirited driving to commercial use.
Excel - The Excel has a medium-high coefficient of friction and maintains stable performance at duty levels from light to heavy. It offers particularly good resistance to wear even at high temps.
Maximum continuous temperature is 225 degrees C, with an absolute maximum of 550 degrees. It too has a maximum rubbing speed of 24 metres per second.
Bendix
Bendix is another major pad supplier in Australia. In addition to a dedicated 4WD-type pad, it shares a range of three general-to-high performance pads. The better of these three are the Metal King Plus and the Ultimate.
Metal King Plus - The Bendix Metal King Plus is a versatile pad that's capable of towing, heavy traffic and steep winding roads. "The hotter it gets, the better Metal King Plus performs" the brochure says. One of its main features is an insulating backing layer between the backing plate and the friction material to isolate heat from the system. It gives good pedal feel, quiet operation, less dust and reliable braking hot or cold. Suitable for "active" or "frequent braking" driving styles.
Ultimate - The Ultimate, as the name suggests, is Bendix's flagship pad. These pads feature a high coefficient of friction for radical high performance braking in sports, performance or prestige vehicles. They were actually designed for OE fitment on some high performance cars. The Ultimates give excellent pedal feel hot or cold and resists fade even under high temps (up to 500 degrees C maximum continuous temp). This low metal pad is suitable for "energetic" and "hard braking" driving styles.
Wilwood
"Wilwood friction pads are produced to specific chemical and physical material requirements to meet the high performance demands of racing disc brake systems".
Polymatrix B type - This newly formulated material has become a popular choice for asphalt and dirt racing. Superb with iron rotors, this pad has a high co-efficient of friction over a wide temp range, stable performance in a predictable and consistent pedal response under all racing conditions. Its uniform heat characteristic reduces hot-spots and cracking, prolonging pad and rotor life.
Polymatrix C type - Wilwood's Polymatrix C material offers a "virtually linear co-efficient of friction in the mid-to-high temperature ranges, assuring drivers of pedal predictability and non-fade with an extremely wear rate."Used on many types of circle track and road racing cars, Polymatrix "C's" high torque output is available to fit Wilwood's Superlite, GN, GT, GT 4000, GT III and GT 6000 calipers.
Polymatrix D type - Specifically formulated for performance street and moderate to heavy dirt track use, Polymatrix "D" brake pads provide immediate and predictable response at low to medium temperatures. As with all Polymatrix pads, the "D" pads wear well, are easy on rotors and "bed" quickly and easily. A true high performance pad with wide application.
Gator Pads (Green Colour) - This compound has been formulated to provide extremely high coefficient levels at low to mid temperatures making it a good choice for dirt and moderate asphalt racing. The material provides a high level of brake torque with minimal pedal effort and works well on both iron and steel rotors. Works well as a qualifying pad on short track asphalt ovals.
A'PEXi
A'PEXi, probably Japan's biggest aftermarket name, offer three different high-performance brake pads - the N1PAD, Carbon Composit and Hyper Street. They are designed to suit Japanese vehicles and some Europeans.
N1PAD - The N1PAD is an extra stable pad that holds a coefficient of friction of 0.5 until about 645 degrees C, where it tapers off at a reasonably rapid rate (in comparison to the other A'PEXi pads). Up to this point though its performance is perfectly linear. It's a great pad for the street where you're generally unlikely to exceed 600 degrees C. Rotor wear may be higher than the other A'PEXi pads.
Carbon Composit - This hi-tech pad offers a higher level of cold braking performance than the N1 and extends its 0.5 co-efficient of friction to a higher temperature. Ultimately it has better overall performance than the N1PAD, but it is less linear. This would be a great pad where high temps are likely to be encountered as its co-efficient of friction drops off very gradually near its limit.
Hyper Street - The HS offers a cold braking co-efficient of 0.3 and gradually increases to just over 0.4 by the time it reaches 600 degrees C. It then continues to operate more effectively right up until around 750 degrees C, where it matches the performance of the carbon composit pad. Basically, until its thermal limit, the hotter it gets the better it performs.
Endless
Another major Japanese brake pad distributor is Endless. Established 11 years ago, the company is now enjoying considerable success in motorsport and has extended its range to cover road cars.
Type NA-Y - Designed exclusively for street use, with an emphasis on effectiveness at low operating temperatures. Its lack of asbestos also means that unpleasant noise has been minimised. It comes with an appropriate rotor temperature range of between 50-350 degrees C, together with a coefficient of friction of between 0.3 and 0.5.
Type NA-S - This pad combines "aramid fibre and ceramics, carbon power and other materials combined by Endless' own blends and processes". On the street, it delivers the necessary response at the low temp starting point, and at the same time it maintains low noise levels. Its rotor temperature range is between 70-450 degrees C, and it packs a co-efficient of 0.3-0.4.
Type NA-M - "A top class brake pad for street use". In addition to an excellent initial brake force, this pad also has improved brake control performance. It's best suited to high powered and heavy sedans. It operates well between 100-480 degrees C, and bites with an average coefficient of friction of 0.3-0.4.
Type NA-R - A pad developed to "enhance the feel of the brakes, maintain controllability and a stable braking force until the chequered flag". This is a specialist circuit pad designed for circuit and grass racing. It operates between 300-800 degrees C, with a coefficient of 0.3-0.4.
Contacts:
http://www.hawkbrake.com/catalog.htm
http://www.apracing.com/
http://www.bavauto.com/pagid/pagid.html#comp
http://www.bbagroup.com/mintex/index.htm
Wilwood - http://www.magnumforceracing.com
A'PEXi & Endless - www.japtrading.com.au
QFM (Race Brakes)
+61 3 9326 6088
Ferodo Australia
+61 2 9604 7111
Bendix
1800 819 666