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For general information on how disc brakes work - Read This:
http://www.brakeinfo.com
or
http://auto.howstuffworks.com/disc-brake.htm
Brake Pad Bedding-in:
For optimal use of any given brake system, the pads and rotor have to be compatible with each other. The bed-in procedure establishes that compatibility between the pad and rotor. This is achieved by a combination of rubbing speed, temperature, line pressure, and Inertia. Bed-in is also influenced by pad and rotor material chemistries. It is always recommended that only compatible pads and rotors be used in any given application.
Bedding in advantages:
1. Gradually heat treats the rotor and eliminates any thermal shock in the rotor.
2. Burn off volatiles and moisture from the resin that is near pad surface.
This will eliminate “green fade.”
3. Establish a layer of transfer film about a few microns thick on the rotor surface. Shearing of the film during friction is an effective source of friction force. Otherwise, when using a freshly ground rotor without the transfer film, the main friction force would come from cutting, plowing, or scoring the asperities on the rotor surface. This leads to inconsistent braking effectiveness.
4. Mate the two surfaces to a near perfect geometrical match, so that the contact area is high, and therefore the friction force is increased.
5. The performance of a fresh rotor/fresh pad system would be inconsistent. This is due to ever-changing structures and properties of the two mating materials. Bed-in of pads and rotor will form a stable transfer film.
6. If bedding in procedure is not applied, a stable transfer film may not be established for a long time. In other words, the rotor surface would have to be constantly regenerating a film that is not quite stable for a long time. This effect would reduce the performance and increase the wear.
Hawk Brake Pad Installation Procedure
Step 1:
Install Brake pads properly. Be sure pads are securely positioned in the caliper.
Step 2:
Flush system with fresh brake fluid.
Step 3:
Check all hydraulic parts for excess wear and tear.
Step 4:
Check disc for proper thickness, parallelism, and lateral run-out.
Step 5:
Check disc for scoring or grooves over .012" depth. If either applies, resurfacing or replacement is required.
Step 6:
If disc does not need resurfacing then contamination from the previous brake pads must be removed. Sand discs with Garnet sandpaper using moderate pressure. Use soap and water to clean off disc surface after sanding and machining. Discs should be free and clear of oil, grease, and brake fluid.
Step 7:
Inspect calipers for freedom of movement. Lubricate where necessary.
Hawk Brake Bedding-in Procedure
Step 1:
Make 6-10 slow-downs from approximately 30-35 mph to 5 mph. applying moderate pressure. Do not come to a complete stop.
Step 2:
Make an additional 2 to 3 harder stops from approximately 40-45 mph. to zero.
Step 3:
DO NOT DRAG THE BRAKES! (after stopping - do not leave your foot on the brake pedal)
Step 4:
Allow 15 mintues or more for the brake system to cool down.
Step 5:
Your new Hawk pads are ready for use.
Ferodo Brake Bedding-in Procedure
Rofren Brake Pad Bedding-in Procedure
(see website)
SP Performance Rotor Installation Guide
Download SP Performance rotor installation guide here (PDF)
NOTE: SP Performance Rotors are direct-replacement parts.
They are the same size as the FACTORY ORIGINAL parts.
If you are looking for rotors that are different diameters, thicknesses, bolt-patterns, etc. than the ORIGINAL part for the car....
We recommend that YOU determine what vehicle (year, make, model) has the rotor size that you are looking for.
Otherwise, you may want to take advantage of our Consulting Service.
Our Telephone Support/Technical Assistance Policy:
Let us be very clear about this -
If you're planning on calling us to ask questions like :
- How does your product compare to XYZ product that you don't sell?
Why is your product better than XYZ product?
We don't answer questions relating our products to those which we haven't used ourselves or don't sell. We have more technical information regarding the products we sell on our website than almost any other manufacturer or distributor. Please read it - then you'll know.
If not, we recommend calling the other company or vendor and asking them the same question.
How long (many miles) is this product going to last on my car?
The short answer is: If you don't drive the vehicle - they'll last forever.
Otherwise, brake component life expectancy is dependent upon:
How you drive, What you drive, and the Conditions under which you drive your
vehicle. Brakes are supposed to wear out!
All of the components we sell should last as long, if not longer, than any normal stock component - and perform better during their life expectancy. In many cases- our customers report anywhere from 150% to 300%+ greater
mileage than from stock components.
Our advice, and the answers to 99% of your questions are available for reading below:
How can I Improve my vehicles braking performance?
Brake performance will be positively impacted by improvements in the following areas:
#1) Better Tires
#2) Better Brake Pads
#3) Larger Diameter Rotors (more brake torque)
Assuming that you have good tires on your vehicle- the simplest, and most cost effective improvement comes from BETTER BRAKE PADS.
What brake pads are the best? (Our Number #1 Asked Question)
The answer here is subjective. Only you know what you want out of your braking system. Some want more performance- some want less dust, etc... Every manufacturer that we carry is a 'class of the field' performance brake pad manufacturer. If there was ONE pad or ONE compound that was better than any other- then we wouldn't have all of these different manufacturers - would we?
In general, we always recommend using a high-quality, semi-metallic pad.
Semi-metallic pads offer premium stopping power and fade resistance. Many of the semi-metallic or hybrid pad compositions also offer very low dust and are noise free.
Lastly, I can tell you this: BRAKING IS A TRADE-OFF
You cannot have better braking perormance with less dust and/or less rotor wear. If you want better stopping power- then that comes with the price of potentially more brake dust and more accelerated rotor wear. If you give up a degree of performance- then you can have less dust and less rotor wear.
You cannot have your cake and eat it too!
Well -actually - you can - but we don't sell them - the product you need can be found HERE.
Why don't you recommend Ceramic Brake Pads?
Let's start by saying that ceramic brake pads have a place in the automotive industry. They were designed to be a low-dust, noise-free brake pad. They came into popularity after the discontinued use of asbestos-based brake pads. At that time, semi-metallic pads exhibited problems with higher noise and dust levels.
That being said, I can tell you that Ceramic Brake Pads were NEVER designed to be a performance brake pad! Some companies have done a terrific job marketing their higher-priced, ceramic pads to the consumer as a performance pad. Ceramic brake pads typically have lower friction coefficients, and act as an insulator - raising rotor temperatures in cast-iron disc systems. When you have a vehicle that has persistent braking problems- the last thing you want to do is install components that have a LOWER friction coefficient and that RAISE effective operating temperatures! See our section on how this can cause ' Warped Rotors "
Premium-grade semi-metallic or hybrid pads are more effective for handling elevated temperatures and dissipating heat away from rotors. Most, if not all, semi-metallic pads have a degree of ceramic content ALREADY IN the brake pad.
Premium-grade, semi-metallic pads can offer LOW-DUST, NOISE-FREE Performance without sacrificing stopping power and increasing rotor temperatures!
Most organizations with fleet vehicles and other extreme-service applications already know what we're telling you: High-quality semi-metallic pads offer the best combination of stopping-power and extended-wear of any brake pad type on the marketplace today!
Should I use the same components as specified as OEM?
OEM means Original Equipment Manufacturer.
Translation: A component manufactured by a third-party company and selected for use in the original vehicle. An OEM manufacturer will typically manufacture their part based on specifications and designs supplied to them by the vehicle manufacturer.
Your vehicle manufacturer selects components used in your vehicle based on a variety of factors. These include PRICE, quality, deliverability, and many others.
In most cases, the manufacturer will not select the BEST product available.
If all of the items that went into your vehicle were the best - your car
would cost 5-10 times as much as you paid for it!
The manufacturers certainly make decisions, in most cases, to use an adequate product- that meets their demands for price and quality. They may not use the cheapest component- because it would result in too many warranty returns.
However, there are thousands of recalls every year for components which the manufacturer has deemed defective.
You can check them out for your vehicle here:http://www.alldata.com/recalls/
The vehicle manufacturers make mistakes too!
In the aftermarket, you can choose from a range of lesser-cost, lower-quality components OR higher price, higher-quality components.
You have the choice!
Just because it was specifed as OEM- it doesn't make it better!
All of the components we sell are EQUAL TO or BETTER THAN the OEM specification for the original component.
Remember, Firestone tires were OEM on Ford Explorer trucks .
Did that make them better? Think about it!
How hot do my rotors get when braking?
Excel calculator is available on the website.
Feel free to change the values, and see how this changes the outcome.
The table above calculates an "average" temperature rise for your rotors
under a single-stop event.
Peak rotor temperatures can be at least TWICE as high as what is calculated .
Higher rates of deceleration will increase the peak rotor temperature more -
since the braking system has less time to dissipate the heat generated.
Under multiple decelerations, the temperatures move progressively higher -
because the rotors do not have a chance to cool to ambient temperatures.
What causes brake pad failure?
There is no single answer to this question - there are simply too many variables.
However, in general, pad failure is caused by excessive heat. Brake pad compounds are designed to operate within a certain temperature range. When the pad is overheated to a temperature above what the material was designed to handle- it will wear at an excessive rate, crumble, decompose, and the like.
Tip: Our Temperature Indicating Paint Kit may be useful in determining the
correct brake pad compound(s) for your application:
http://www.raceshopper.com/temperature_paint.shtml
What causes brake pad glazing?
Brake pad glazing is caused when the brake pad friction material is overheated.
This results in crystallized friction material on the pad surface and the brake disc.
Typical symptoms of glazed brake pads include: Poor stopping performance, vibration or brake judder, and cracks or fissures in the brake pad material.
Pad glazing is typically caused by operating the brake pads at a temperature above the specified temperature range of the friction material or not properly following the 'Bedding-in' instructions for the brake pads. Always follow the manufacturers brake pad bedding-in instructions and use a brake pad that has a temperature range that is sufficient for its intended use.
What is better- Slotted or Drilled Rotors?
Again - this is a subjective question. As they say- liars can figure- and figures can lie. Proponents of both sides will espouse the benefits of each.
We prefer 'Slotted Rotors' Why?
A few different reasons:
1) Many companies who produce aftermarket performance rotors may not use the best 'blanks' to start with. They do this because it allows them to make the rotors at a lower cost and sell them to you for less than other competitors- or, this way, they can compete with the larger manufacturers. Now, if you have a somewhat sub-standard rotor- and then you 'cross-drill' it - What do you think you're doing? Well, you're compromising the integrity of the rotor by drilling completely through the surface- and then it heats up- and if it isn't a quality blank- made from quality steel and alloy- What do you think happens then? Well, more likely than not- it will crack.
Remember, we're not saying ALL 'Cross Drilled' rotors are bad.
2) Cross-Drilling (in most instances) removes more braking surface area than slotting does.
3) A brake rotor is designed to do one thing: Convert kinetic (moving) energy to thermal energy (heat). What handles more heat- A cast-iron kettle or a pizza pan with holes in it?
4) Can you think of any professional race teams who still use cross-drilled rotors?
Most importantly: "You get what you pay for!"
If you buy a $20 set of brake pads or a $30 rotor- and then you have to change them every 5,000 or 10,000 miles - Is that really a bargain?
Why all performance rotors are not created equally ...
Here's a few examples:
Here's an instance where the time was not taken to create a program specifically for the rotor in question.
The result is that the machine has drilled though one of the cooling veins and has compromised the structural integrity of the rotor. SP Performance creates application-specific programs for every rotor that it manufactures - This insures performance, safety, and reliability.
Here's another example of improper engineering.
Incorrect programming and layout has caused the drilling and slotting pattern to be non-symmetric.
To 'fill in the gap' additonal randomly-spaced holes had to be inserted to 'make the rotor look right.'
This can create a situation where the rotor in question would be out of balance.
SP Performance ensures the highest quality and performance by creating application-specific
computer programs for every rotor that it produces.
All SP Performance rotors are custom machined by highly-skilled, factory-trained technicians, and the rotors are computer balanced after manufacturing.
It takes a little bit longer and may cost a bit more, but- ask yourself......
What would you rather be riding around on?
Are Big Brake kits really better?
Big brake kits that are incorrectly designed can acutally perform worse than your stock brakes. Bigger pads and rotors primarily do one thing: They dissipate more heat than the stock brake setup. They do not necessarily stop you in shorter distances. Stopping distances are impacted by the coefficient of friction of the brake pad used and the clamping force applied by the caliper. Bigger brake pads do not apply more pressure- they only apply the same pressure over a bigger area. But- Don't take our word for it:
Here's a link to the test data for StopTech with their upgrade kit on an Audi S4:
http://www.stoptech.com/technical/balancedchart.htm
Note the next closest stopping disance in the chart is the OEM system!
Here's another link to another test using a Nissan 350Z:
http://www.zeckhausen.com/testing_brakes.htm#Summary
Note that the stock brake system on the 350Z (non track model) utilizes a 11 3/4" front rotor. For their test- they upgraded this to either a 13" or 14" rotor!
So- you can put a 13" or 14" rotor on the front of the car - and it still only stops about 7 feet shorter than the stock 12" rotor.....
We applaud StopTech- they seem like good people- and they are one of the few companies providing REAL information. They tell you exactly what we tell you earlier:
If heat dissipation is of primary concern- then a big brake kit will reduce the rotor and caliper temperatures. Otherwise, Premium Grade Brake Pads with higher temperature range capabilities and a higher coefficient of friction will provide the best improvement in braking performance.
Can I use racing brake pads on the street?
Simple answer: NO. Why?
We're not your parents- and we can't TELL you what you can and cannot do-However, If you use racing pads for street driving - a few things will happen:
1) YOU WON'T STOP. In fact, you will probably blow-through the first 2 or 3 stop-lights, stop-signs and the like everytime you first get in your car and drive it. FACT. Just like other brake pads- racing pads are engineered to operature at a CERTAIN TEMPERATURE RANGE. They will not stop you for a hill of beans BEFORE they get to that temperature range.
2) YOU WILL DESTROY YOUR ROTORS. Racing pads are a much harder compound than streetable pads. When these pads are cold- they produce an EXCESSIVE amount of wear on the rotors. In some circumstances- the pad material can be 'as-hard-as' - if not 'harder-than' the rotor material itself!
Take a look at a Formula1 race sometime- you will see the team throwing out $1,000.00 Carbon Fiber Rotors after every session - and the pads are still good!
What makes Brake Pads work?
If you got to this section- You are a die-hard braking fanatic! - Congratulations! Now onto the SCIENCE OF BRAKING!
The simple answer is friction. BUT- that's only part of the answer!
Brake pads work with a combination of TWO FRICTION TECHNOLOGIES:
1) ABRASIVE FRICTION
This involves the braking of molecular bonds between the pad material and the iron in the brake disc. Pads that function on this basis (typically organic pads) tend to have a high wear-rate and low resistance to high-temperature brake fade.
2) ADHERENT FRICTION
Adherent friction is developed when a transfer-film of the same compound of the pad material is deposited as a very thin 'film' on the surface of the rotor.
In this instance, the friction is caused by a breaking of molecular bonds between the two like friction materials amongst themselves (one on the pad and one on the surface of the rotor)
Most performance brake pad manufacturers now manufacture pads that function as a combination of these two technologies. These pads tend to have higher coefficients of friction over a wider range of temperatures.
All of the manufacturers that we carry - Hawk, Ferodo, and Performance Friction use a combination of abrasive and adherent friction technologies to stop you safely- Whether it's going to the corner store- or slowing from 220 MPH in a F1 or Indy Car!
You can benefit from the same technology that race drivers like Jeff Gordon, Michael Schumacher, or Michael Andretti use to stop their race cars !
What causes 'Warped Rotors'?
Typically warped rotors are caused not by a failure of the rotor itself.
Warped rotors (in most instances) are caused by the brake pads being operated at temperatures outside of their specified range. When the pads get too hot the pad material actually melts and 'fuses' itself to the rotor surface and creates a 'bump' on the surface of the rotor. In most cases this is not noticeable to the naked eye. This creates an annoying vibration when the brakes are applied. The only solution to this is turning (grinding) the rotors or installing new rotors.
We do not recommend turning rotors: It removes additional metal and reduces the the thermal capacity of the discs.
The best way to combat this condition is to use GOOD QUALITY street performance brake pads which have a higher operating temperature range.
Properly 'bedding-in' the pads and discs is a must.
Tip: Our Temperature Indicating Paint Kit may be useful in determining the
correct brake pad compound(s) for your application:
http://www.raceshopper.com/temperature_paint.shtml
When mounting new rotors- they should be installed on the vehicle and indexed with a dial indicator to minimize runout. New rotor runout is typically between .002" - .005" However, failure to mount the rotors ON THE VEHICLE and measure TOTAL runout can cause a vibration even with brand new rotors. You should check hub runout as well- since a very small amount of hub runout (even as small as .002") can create additional runout of as much as .006" - even with perfectly true rotors.
This is similiar to mounting and balancing tires. Often times a rim and tire combination that would require additional weight to correct balance can be rotated and then require less or no weight to balance.
This means you should test the rotor in a number of configurations and install it in the confirguration which results in the LEAST amount of total runout.
What makes my brakes squeak- and how do i fix it?
Ok, here's the answer:
http://www.delphi.com/pdf/techpapers/1999-01-0142.PDF
It's 8 pages long- and will tell you exactly what causes brake noise.
Did you read it? No? Ok, We'll summarize it briefly: High-pitched brake squeal is caused by a high-frequency vibration between the pad and the rotor. Brake noise is not caused solely by the brake pad. The brake rotor diameter, and stiffness of the disc are also factors in the offending noise. Metallic-Carbon pads (as opposed to organic (asbestos) pads) typically produce more inherent noise than the older organic pads. Different brake pad manufacturers use different and varying amounts of substances in their pads: Iron, Copper, Zinc, Other Alloys, Lead, Carbon, Ceramic compounds, Kevlar, and numerous other fillers. This variation in pad composition, geometric design of the pad, and the stiffness (density) of the pad material itself can also contribute to the noise. Lastly, all of these factors can be affected by environmental factors such as temperature and humidity.
Now, how do I fix it?
#1: Make sure you have straight and true surfaces on your rotors and pads. Turn, or replace rotors as necessary- do the same with the pads.
#2: Inspect calipers, caliper sliders, and all other mounting sufaces and metal-to-metal contact areas. (This includes the rotor to hub mounting surface which commonly becomes contaminated by rust and other debris!) Lubricate all metal-to-metal contact areas with moly grease or lube. Inspect complete system and make sure that rotors and pads are lining up 'true' when brakes are being applied.
#3: Apply anti-squeal moly lube or similar to backing plate of the pads - or use an anti-squeal shim between the pad and the piston contact areas. This will change (dampen) the frequency of the vibration and will help reduce the noise.
#4: Chamfering of the leading and trailing edge of the pads will also help to reduce noise levels.
#5: Inspect related suspension components to make sure worn components are not placing undue stresses on the braking system, calipers, and pads.
Still not fixed? Ok! - You've got a tough one! We recommend going here to get your Doctorate in Friction Science:
http://www.frictioncenter.com
I hope you remember your ThermoDynamics lessons from Physics class!
Do I really need these more expensive, premium-grade components on my car?
Consider this:
In most instances, car disc brakes and rotors will last anywhere from 30,000 to 60,000 miles or more before needing replacement. If we estimate on the conservative side- and say they only last 30,000 miles- and the typical cost of premium components (rotors and pads) may cost $300.00 That averages out to a cost of 1 CENT PER MILE.
Now, what does it cost to put gas in your car?
You pay probably $1.50 per gallon for gas- and get approx. 30 miles per gallon. Based on that, you are currently paying 5 cents per mile- just for gas!
That's over FIVE TIMES AS MUCH as you pay to maintain the braking system on your automobile!
How much is it worth to maintain your vehicle's proper braking operation, your safety, and have the benefit of improved braking performance over the lifespan of the components?
In fact- the true ADDITIONAL COST of premium components is probably less then 1/2 OF ONE CENT - since inferior replacement parts typically do not cost less then half of the price of the premium parts we sell.
The 'Lifetime Warranty' Myth:
Some manufacturers and repair shops offer brake parts with a 'Lifetime Warranty'. Why do you suppose this is?
Without question, every brake component will fail with eventual use.
It is a wear part.
Could it be that these companies have an incentive to have you keep coming back time and time again?
More disconcerting is this fact: Inferior parts will fail sooner than Premium grade parts. Installing inferior brake components will cause not only the part in question, but also OTHER PARTS TO FAIL SOONER.
You decide:
Is it worth it to buy an inferior part- and keep getting it over-and-over again replaced for free- BUT have to pay labor, and pay for other brake components that have failed as a result of the part in question- OR
Would it be easier to buy the best, Premium Grade Components and have them last?