As more and more of our customers join us for track days and even racing, the question often comes up – do I need a special helmet to go on track?

The answer is YES, and a car helmet is NOT the same as a motorcycle helment….so, don’t bring your bike helmet to a car event.

The next question is, “do I need a special type of helmet?”    The answer is again YES, it has to be a 2000 or newer helment, meeting a minimum of the SNELL 2000 regulations, and next year (2011), the minimum will be SNELL 2005.   The SNELL regulations are updated every 5 years, and most driving event sanctioning bodies as well as the race sanctioning bodies update the requirements to be in sync w the SNELL ratings.

So, for 2010, you must have a SNELL 2000 or newer approved helmet.

What does the SNELL approval mean?  And, once you read these, you’ll be thankful these exist…as the standards are not “pie in the sky” type requirements, but requirements that could occur during a real accident or incident.

(a) To meet the SA2010 standard, a helmet must be able to withstand a 1450 F degree propane flame for 30 seconds, during which the padding inside the helmet can’t get hotter than 158 F degrees.

(b) The visor shield must resist piercing from a one-gram lead  pellet fired at it in three locations at a speed of 311 mph.  The same shield must also endure that 1450 degree propane torch for 45 seconds without melting.

(c) The Snell standard says the helmet just the head by no more than 275g after being hit with an anvil at speeds as high as 17mph.   Certain related elements subject helmets to three of these hits in a row.  And, the helmet’s structure must remain intact, preventing any any object from making contact with your head.

Helmets get lighter and stronger, but nonetheless, they must provide the kind of protection required in real world situations.

And, if you ask us, “open face or closed face helmet?”, we will always recommend closed face helmets.

So….of all the helmets out there, which ones do we like?    Arai, Bell, and Simpson are our choices.   Arai is the most expensive, usually the lightest, and the tightest fitting.  Bell usually has the best overall fit and comfort, and the largest eyeport.  Simpson has a broad range of styles, is usually lighter than the Bell, but not as light as the Arai.  But, all helmets must be tried on to know if they will work for you.

Cheaper versions of the helmet normally come in group sizes (S, M, L, XL).  More expensive helmet versions come in hat specific sizes ( 7 1/2″).   We just got new helmets again, and we choose Bell Dominator w HANS attachments.

Be Safe….have FUN.

There are lots of brake kits out there….but BRracing has chosen to focus and only promote two manufacturers….Brembo and StopTech.  So, why?  What makes these brakes so special?  And why even do a big brake kit for a street car?

First, most street cars do not come from the factory with a brake system that can really handle the rigors of a track day.  Upgrading the brakes, even if it’s initially just the pads, fluid, and brake lines, may be the single most important upgrade you can make to your car if you plan on tracking your car at any point in the future.  That’s where performance brake manufacturers come in, like StopTech.

StopTech was founded in 1999, and is led by a group of auto enthusiasts and racers.  StopTech was acquired by Centric Parts in 2006, one of the largest suppliers of brake and hydraulic parts in the U.S.  Centric Parts is led by Dino Crescentini, whose name may be familiar to those who follow Speed World Challenge, where he drives a Porsche.  Centric also acquired PowerSlot in 2007, and PowerSlot rotors are now manufactured in the same facilities as StopTech components.

The majority of the components made in StopTech’s Compton CA headquarters are sold for street/track applications, such as big brake kits.  StopTech is also deeply involved in racing, the ultimate proving ground for its products.  Team in both World Challenge and Continental Challenge use StopTech brakes, including Turner Motorsport and GMG, who won the manufacturer’s championship for Porsche.

StopTech sources iron brake rotors from several foundries in North America, and holds all of them to the same high standards for quality, which were refined in part through StopTech’s process of German TUV certifications.  StopTech requires additional content to be used in the iron as well as additional investment in the foundry process to give their rotors maximum durability (they even found that sourcing iron from foundries from some other parts of the world produce rotors that did not meet their product requirements, so they are very specific where their core iron comes from).

StopTech’s AeroRotors feature aerodynamically designed cooling vanes cast into the rotor itself to help reduce rotor temperatures.  The patented vane design elements are created to induce maximum maximum cooling airflow through the brakes when they rotate.  But, they don’t just optimize the airflow, the inner vanes are designed in such a way as to provide equal cooling across the rotor race.  Think…as the air enters the inner rotor face, it is cool.  But, as it passes through the rotor, heat is transferred to the passes air, and the cooling at the outer edge needs to be the same as the inner edge so that there is not a heat gradient created across the face of the rotor.  Hence, the vane design at the inner edge and the vane design at the outer edge are NOT the same.  They also spent time figuring out the leading edge of the vane, so as to optimize the directing of the air through the vanes and rotor passage vs creating turbulence.  So, when you look at a “slotted” rotor….don’t just think of them as all being the same.  Just going from a typical straight vane original equipment rotor design to a directional rotor can have tremendous benefit.  StopTech points out that one racing team using PowerSlot directional vane brakes in the Grand-Am Continental Challenge ST class experienced an 80 degree reduction in rotor temperature compared to OE rotors of the same size at the same track.

If you were to ask StopTech’s position on drilled vs slotted rotors, since they make and sell both, they would tell you that “drilled” rotors will crack sooner than “slotted” rotors.  They’ve done back to back testing where a slotted rotor is substantially more resistant to cracking than a drilled rotor.  One thing that is important with a drilled rotor is the actual hole pattern…it’s not just a bunch of random or equally spaced holes in the rotor.  They must be placed to avoid weaknesses in the part itself.

Now…what about the other parts?   StopTech uses forged calipers for all their products; they believe this gives advantages in grain flow and density versus calipers that are manufactured in a casting process.  The metal quality of a forging also allows a reduction of material from areas of the caliper that experience lower stress during use, which allows StopTech to reduce weight without affecting stiffness.  This is part of the overall performance optimization that goes into each StopTech design.  (This same thought pattern applies to the wheel market, where forged wheels are widely recognized for their strength and weight optimization vs cast wheels).

StopTech emphasizes maximizing stiffness in each of its caliper designs.  Rather than go with monoblok calipers, StopTech uses bolted assemblies; this they believe improves the stiffness of the caliper and is worth the added weight that comes with it.  A stiffer caliper is more efficient in applying braking forces and also allows more even brake pad wear.

If you dive deeper into the design of the StopTech brakes, there are more features that distinguish them from the other players.  Some brake manufacturers actually only make a couple of caliper designs, and just use the caliper mounting hardware to allow the kit to fit each car.  StopTech takes a much different approach.  It has over 35 different caliper designs, and further refines each caliper by sizing the caliper pistons to the size needed for the braking capacity being designed for the particular application.  This can especially be seen in the calipers for the Porsche product line vs the BMW product line, where you have a rear engined car vs a front engined car.  We have seen this in our GT3 kit vs the BMW E82 135i that we worked with them directly on.  Same overall caliper design, but the pistons on the GT3 are a different size than the pistons on the BMW E82 135i kit.  But…go  one step father….the pistons on the same caliper for the BMW 135i are not the same size….it may be a six piston kit, but each piston has been specifically defined in its diameter to produce the right amount of brake clamping capacity.   Hence, a BMW kit is truly a BMW kit, whereas a Porsche kit is truly a Porsche kit.

What is the difference in the ST kit vs the STR kit?  The STR kit is the full race kit.  The calipers are NOT painted, there is further weight optimization, there are no rubber dust boots around the inner pistons, and there are “quick release” features for fast pad changes.  However, unlike many other manufacturers, the STR kits and the ST kits are exactly the same.  You can run on the street the same setup the leading teams are using on the track.

Finally, we have beaten the crap out of both our BMW E82 135i kit and our Porsche GT3 kit, and they have stood the test….and performed amazingly so.  We have often pulled into the pits and have had our brakes smoking from how hot we have gotten them….but no matter….they just keep on going.  Not only do they perform, they last.

BRracing often takes extra steps when we are installing brakes (pads and rotors) on our customers cars, and we “bed” the new pads and rotors.  This is not something most shops do, or know how to do properly, but when we do it, we often get questions from our customers about what this process is and what does it do.   So, to put the mystery aside, and to help in the understanding of the process, here is the technical background on “bedding”.  Also note, that there is not just one bedding process….it also depends on the type of pads being “bedded”….semi-metallic pads vs organic pads take a different process.  Same theory, but different process.

In order for any brake system to work optimally, the rotors and pads must be properly bedded-in, period. This process can also be called break-in, conditioning, or burnishing, but whatever terminology you choose, getting the brakes properly bedded-in and keeping them that way is critical to the peak performance of the entire brake system, and something that is necessary whether you are doing new brakes for the street, or for the track….both benefit.

However, understanding why the rotors and pads need to be bedded-in is just as important as the actual process. If one understands what is happening during the bed-in process, they can tailor the process to specific pads, rotors, and/or driving conditions. For this reason, we will talk about the generic bed-in overview pertaining to all brake systems, but follow with examples for application-specific bed-in procedures to fit most circumstances.

What is brake pad “bed-in” anyway?

Simply stated, bed-in is the process of depositing an even layer of brake pad material, or transfer layer, on the rubbing surface of the rotor disc (both sides). That’s it. End of discussion. Ok, not really, but although bed-in is quite basic in definition, achieving this condition in practice can be quite a challenge, and the ramifications of improper or incomplete bed-in can be quite a-a-n-n-o-o-y-y-i-i-n-n-g-g.

Abrasive friction and adherent friction

There are two basic types of brake pad friction mechanisms: abrasive friction and adherent friction . In general, all pads display a bit of each, with abrasive mechanisms dominating the lower temperature ranges while adherent mechanisms come more into play as pad temperature increases. Both mechanisms allow for friction or the conversion of Kinetic energy to Thermal energy, which is the function of a brake system, by the breaking of molecular bonds in vastly different ways.

The abrasive mechanism generates friction or energy conversion by the mechanical rubbing of the brake pad material directly on the rotor disc. In a crystalline sense, the weaker of the bonds in the two different materials is broken. This obviously results in mechanical wear of both the pad and the rotor. Consequently, both pads and rotors are replaced when they are physically worn to their limit and are too thin to endure further service.

The adherent mechanism is altogether different. In an adherent system, a thin layer of brake pad material actually transfers and sticks (adheres) on to the rotor face. The layer of pad material, once evenly established on the rotor, is what actually rubs on the brake pad. This allows the same material to interact, and the same coefficient of friction, improving the overall braking capacity vs when “bedding” is not done or not done properly. The bonds that are broken, for the conversion of Kinetic to Thermal energy, are formed instantaneously before being broken again. It is this brake pad-on-transferred brake pad material interaction on a molecular level that yields the conversion process.

With the adherent mechanism there is much reduced rotor wear as compared to abrasive mechanism, but it’s not a free lunch – pads now become the primary wear element in the braking system. And even though rotors are not mechanically worn down with adherent systems, they still will need to be replaced on a regular basis due to cracking reaching a point of failure if they are exposed to intense, repetitive thermal cycling. This is why race teams throw out rotors that are actually as thick or thicker than when they were brand new. It’s due to the an adherent brake pad transfer layer!

The all-important transfer layer

As stated above, the objective of the bed-in process is to deposit an even layer of brake pad material, or transfer layer , on the rubbing surface of the rotor disc. Note the emphasis on the word even, as uneven pad deposits on the rotor face are the number one, and almost exclusive cause of brake judder or vibration.

Let’s say that again, just so there is no misunderstanding. Uneven pad deposits on the rotor face are the number one, and almost exclusive cause of brake judder or vibration.

It only takes a small amount of thickness variation, or TV, in the transfer layer (we’re only talking a few ten thousandths of an inch here) to initiate brake vibration. While the impact of an uneven transfer layer is almost imperceptible at first, as the pad starts riding the high and low spots, more and more TV will be naturally generated until the vibration is much more evident. With prolonged exposure, the high spots can become hot spots and can actually change the metallurgy of the rotor in those areas, creating “hard” spots in the rotor face that are virtually impossible to remove.

Bedding fundamentals

In general, bed-in consists of heating a brake system to its adherent temperature to allow the formation of a transfer layer. When both the pad and rotor have achieved the proper, hot, operating temperature, the pad material actually transitions into a “plasma”, and the transfer of material is that applied and adhered to the rotor surface.  The bedding process then continues, but not at the same “hot” temperatures, to continue the transfer process and to ensure the evenness of the applied layer.  The brake system is then allowed to cool without coming to rest, resulting in an even transfer layer deposition around the rotor circumference. This procedure is typically repeated two or three times in order to ensure that the entire rotor face is evenly covered with brake pad material. Sounds easy, right? Well, it can be if you have the proper information.

Because the adherent temperature range for brake pads varies widely (typically 100°F-600°F for street pads and 600°F-1400°F for race pads), each bed-in needs to be application-specific. One could try to generate a one-size-fits-all procedure, but too little heat during bed-in keeps the material from transferring to the rotor face while overheating the system can generate uneven pad deposits due to the material breaking down and splotching (that’s a highly technical term) on to the rotor face.

In summary, the key to a successful bed-in is to bring the pads up to their adherent operating temperature in a controlled manner and keep them there long enough to start the pad material transfer process. Different brake system designs, pad types, and driving conditions require different procedures to successfully accomplish the bed-in. The recommended procedures below should provide you with the information you need to select the bed-in procedure appropriate for your application.

Can “bedding” only be done once, when the pads and rotors are new?  Nope, the same process can be done during the pads and rotors life, and we have certainly seen on some organic race pad applications where the track use results in uneven pad deposits, and you get the feared brake shudder….so, you can go thru the “bedding” process again to ensure the application is even and ready for use again.  If the pad deposits are too great, the rotors may need to be burnished or freshen before the next step of bedding can be repeated or done again.

For street applications….the bedding can be done on the street, by going thru a general heating up process (3 or 4 stops from 30 mph down to 5 mph, then immediately repeating), then the hard application process (3 or 4 stops from 60mph down to 10mph using thresshold braking….during this process the brakes should actually be smoking…..do not fear this…this is good), then a cooling process of braking (another 3 or 4 stops from 30mph to 5mph with moderate braking pressure).  Finally, the brakes now need to cool uniformly, and you should drive at least a mile without using the brakes at all, and also not let the car come to rest (heat soak could occur due to the heat in the pads and rotors).

Another hint for track users….when you come off the track, do NOT bring your track car into the pits without using the cooling down lap to really cool the motor and brakes.  If you come off a hot lap and immediately head for the pits, but you’re still playing a hot lap on the last lap, and you then roll into the pits as you are so excited from your last set of flyers…and then park the car, the heat in the brakes can “heat soak”, and cause the rotors to warp….this is also why when you are at the track you NEVER put on the parking brake when you park your car or vehicle in the pits….lesson learned from direct experience.