FR-S / BRZ Brakes Upgrade Guide

[JRitt]

Hi Guys,
I've seen a bunch of posts about brake upgrades on the FR-S, BRZ, and GT-86. I decided to write a brake upgrade guide that examines the brakes on these cars. I will look at what comes stock vs. what you may want to try based on your needs. The last part of that sentence is critical. Your upgrade path is going to be heavily dependent on your goals for your car. I'll be writing the article from that angle, looking at how different people will be using their cars. I've completed the first basic part, which will address a large portion of the people on this forum (those who will be doing mostly street driving or autoX). Hopefully this will cut down on some the redundant questions that constantly arise. Also, feel free to ask me any specific questions about brakes in general or these cars specifically. If I don't know the answer, I most definitely have access to people who will!

Qualifier: Why do you care what I have to say about brakes? I've been working in the aftermarket brake business since 2003, and have talked brakes with many thousands of customers driving every type of car under the sun. I currently work closely with AP Racing, who supply brakes to most of the top professional race series in the world. You can see my profile on our website. Thanks.

Okay...on to the good stuff.

I did a video version of my brake upgrade guide...

[ame="https://www.youtube.com/watch?v=E2MznXX4vGc"]Know Brakes 5: High Performance Brake Upgrade Guide - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=kwWqFecWZPc"]Know Brakes 7: How to Plan Now for Future Brake Needs - YouTube[/ame]

Daily Driver

If you never plan to do anything with your FT86 other than drive it to work every day, there’s a solid chance you’ll be perfectly happy with the OEM brakes as delivered. Just about every modern car today has decent brakes, with far superior technology and performance vs. the cars our parents drove when we were kids. OEM brakes are designed for safety above all else. Any and all other considerations are secondary:

• Shortest stopping distance possible- Every once in a while, a kid chases ball into the road, or a deer jumps from the trees at an inopportune moment. The goal is to stop the car in the shortest possible distance to avoid a collision. The basic brake components are selected to achieve that goal based on the vehicle layout (RWD, FWD, etc.), weight, power, tires, etc.
• Stability- Inclement weather, limited driver skill, and chance all create road conditions that negatively impact a vehicle’s stability. Modern brake systems are designed to maintain as much stability under as many conditions as possible. ABS, traction control, and stability control systems all allow a driver to turn while braking, and help keep the car pointed in the desired direction. These systems also contribute to the point above, getting the car stopped and safe as quickly as possible.
• Repeated stops at max load- Manufacturers know their cars will be driven in rush-hour traffic, filled to the brim with gear from a local big box store, and/or possibly towing something at the vehicle’s max recommended load rating. Under those conditions, the car needs to be able to stop repeatedly in an acceptable manner.

Achieving the above objectives are sufficient for most of the cars on the road. For a specialized sports car, such as the FT86, the manufacturer obviously goes a bit above and beyond these essentials. Factors such as pedal feel, pedal travel, pad compound feel, fade resistance under heavier than normal use, etc. all come into play. The manufacturer addresses these issues to make their car a competitive performer in the market, all while attempting to manage their costs as tightly as possible.

If your primary objective with your FT86 is to safely take you from one place to another, you’ll be fine with leaving your stock brakes alone.

Spirited Street Driving

Enthusiasts tend to be a little tougher on equipment than ‘non-car’ people. They accelerate, turn, and brake harder on a regular basis, and they have higher performance expectations. Aggressive driving on back roads, canyons, etc. puts more heat into the brake system than running errands ever could. While manufacturers expect a sports car to be driven harder than a minivan, exactly how much harder leaves a lot of room for interpretation. Your idea of being tough on brakes may differ vastly from the engineers’ thoughts on the subject. Below is a list of upgrades that can be considered for aggressive street driving, in order of importance:

• High Performance Brake Pads- Performance pads will be your number one upgrade for improving brake feel and performance if you plan to drive your car hard on the street. I’ve written an in-depth article on how to choose the proper pads for your needs, so please read that article to learn more about pad selection.
• Slotted/Drilled Discs- If you upgrade your pads and still feel like you’re not getting enough bite out of them, you may want to consider slotted or drilled discs.
  • Slotted discs provide more leading edges for a pad to bite into vs. a plain-face disc, and allow for pad material and water to evacuate the pad/disc interface. They are marginally more prone to cracking than plain face discs, but the added performance of slotted discs is worth the tradeoff to most enthusiasts (assuming the slot pattern is done correctly).
  • Drilled discs, regardless of whether the holes are cast in or drilled after the casting process, are more prone to cracking than plain face or slotted discs. They do provide even more leading edges for pad bite, and a slight weight reduction. They also look snazzy.
  • Slotted and drilled discs will wear your pads out more quickly than plain face discs. All of those leading edges assist with bite, but also increase wear rates.
  • Holes and slots will also make more scraping and whirring noises than plain face discs, so there are some NVH (Noise Vibration Harshness) tradeoffs as well.
• Stainless Steel Brake Lines- While most people won’t notice a tremendous difference under street driving conditions, SS lines can enhance pedal feel, offer greater protection against road debris, and offer a slightly faster reaction time for brake activation.
• High Performance Brake Fluid- It is highly unlikely that you’ll boil your brake fluid under aggressive street driving. The more likely scenario is that you’ll only need to flush your brake fluid at regular service intervals. When you do, it never hurts to go with a slightly higher spec than stock if you plan to drive your car hard off the beaten path.

AutoX

Autocross presents a unique challenge for your car's brakes. Depending on the course layout, the amount of pad heat generated may not be any greater than stop-and-go traffic driving. Many times you never get out of second gear, which means speeds are generally limited to roughly 60 mph or less. Additionally, the flowing nature of a well-designed autocross course means that you don't always scrub off a tremendous amount of speed entering each brake zone. More often than not, you're trail-braking as you approach the apex of the corner, rather than standing on the brakes in a straight line. Therefore, precise control and feedback is what you're looking for in your brakes. Here are some brake upgrades to consider if you autoX your car:

• High Performance Brake Pads- As I discuss at length in my pads article, you’ll want a brake pad with good cold bite, predictable torque response, good all-weather performance, and a simple bed-in procedure.
• Slotted/Drilled Discs- Braking feel is extremely important in autocross, so for many drivers, slotted or drilled discs are worth the investment for the added touch they impart. Wear rates and NVH are secondary concerns when you’re fighting for every hundredth of a second. Additionally, drilled discs in particular can offer a tangible weight reduction, which can be critical in AutoX.
• Stainless Steel Brake Lines- As with discs, every little bit of added feel can mean the difference between winning or losing in a tightly contested AutoX. As such, properly made SS lines are a no-brainer upgrade with no downside.
• High Performance Brake Fluid- While fade isn’t typically an issue at AutoX, your increased maintenance and continual setup changes will mean that you’re under the car tinkering with your brakes more than you would be if you were only driving it on the street. As such, keeping some high quality brake fluid in the car as added insurance never hurts, nor does a good bleed for maintaining a firm and sensitive brake pedal.
• Two-piece Brake Discs- Unsprung weight is the devil to the avid autocrosser. You should always be looking to maximize weight reduction within the boundaries of the rules (or outside those boundaries if you’re really clever at cheating). Weight reduction in the wheels/brakes/suspension area is particularly beneficial to all aspects of acceleration, turning, and braking, which is the core of autoX. Two piece discs can in some cases offer substantial weight savings. Aftermarket two-piece discs will have aluminum hats that are lighter the stock iron pieces, and their overall construction and vane structure may offer further weight savings. Since you probably won’t be burning your discs up at a rapid rate, the initial cost of a two-piece disc may be worth the weight loss (commonly $600-$1000 per pair). Definitely check the price of replacement iron before making the commitment however. You will eventually have to change the discs since they are a wear item. Also, keep the size of the disc in mind. A larger than stock 2-piece disc may actually weigh more than the OEM units. Also, the larger the diameter of the disc, the greater the moment of inertia, which makes it more difficult to spin the disc from rest.
  • For reference, the OEM BRZ front discs weigh 17.0 lbs. each, and the rears weigh 13.2 lbs.
• Caliper Upgrade- A caliper-only upgrade could be a viable weight reduction option if the calipers are designed to work properly with the FT86 master cylinder and discs.
  • Aluminum, fixed-piston, opposed calipers tend to weigh less than OEM cast slider calipers. The OEM front BRZ caliper and bracket weigh 11.6 lbs., while each OEM rear caliper and bracket weighs 5.8 lbs.
  • However, slapping the calipers from a different vehicle on the FT86 can be a recipe for problems. While the parts may technically bolt onto the car, the actual performance may actually be significantly worse than stock. The main reason for this being improper brake bias. I will address this issue several more times throughout this article.
  • Assuming bias is correct, in addition to a solid weight reduction, fixed piston opposed calipers tend to offer substantially better feel, modulation, and a faster response than OEM sliders/floaters.
  • If the aftermarket caliper has substantially larger pads than stock, some of the overall weight savings may be offset by greater pad weight. For reference, the OEM front pads weigh 1.8 lbs., and the rears weight 0.8 lbs.
• Big Brake Kit/Complete Competition Brake System- A complete brake system could be beneficial in AutoX for several reasons:
  • Feel- Far stiffer, opposed piston calipers can offer dramatic changes in brake pedal feel and modulation. Some highly competitive types will find it worth the price of entry for this reason alone.
  • Brake Balance/Bias- Getting the proper balance is very important for AutoX, and is closely related to the feel point above. If the piston sizes and disc diameter are not chosen carefully and properly (assuming you won’t be touching your OEM master cylinder), you will likely hurt your performance rather than help it. Increased (longer) stopping distances (the opposite of what you want), long brake pedal travel, and poor brake pedal feel are just some of the potential negatives of a poorly engineered system.
  • Weight- Many complete brake kits shave weight over the stock setup. Even if the stock components and aftermarket components are the same physical dimensions, the aftermarket setup will be lighter 9 times out of 10. Aluminum calipers and aluminum disc hats are typically lighter than the OEM sliders and one-piece discs. As an added bonus, the optimized components can offer a host of benefits if you also track your autoX car. On the other hand, if you add a system with extremely large discs and a huge eight piston caliper, you may be adding unnecessary unsprung weight and rotational mass to the car, and actually hurting your performance in autoX.

HPDE (High Performance Drivers Education)/Time Trial

(Much of what is written below is borrowed from my pad article, but I believe it is important so I'm including it here. Some of it is modified to be specifically applicable to the FT86, so it may be worth a read even if you read my pad article.)
On a road course, you will always put more heat into your brake system than you will on the street or at an autoX. Please reread that sentence. HPDE is really the first venue I've mentioned thus far where battling heat becomes the critical element in having an effective and reliable brake system.

One of the most interesting aspects of HPDE is the wide range of speeds and driver ability across run groups. As such, it's difficult to recommend a blanket brake solution for an FT86 driven at a HPDE. As more and more people modify and drive these cars on tracks, we'll begin to get a better idea of what the typical and maximum brake demands will be. After countless discussions with customers on this topic over the years, I believe there a few key considerations when upgrading your brakes for an HPDE or Time Trial: Driver experience, track layout, vehicle configuration/modification, and tire choice. A careful examination of these factors in your personal situation should help guide you towards an acceptable brake solution. Keep in mind that all of these factors are related, and cannot be considered in isolation from one another.

Driver experience
If you've never driven anywhere but the street, your first couple of trips to the track will most likely not tax your brake system too heavily, right? Not exactly. You being a complete track newbie won't necessarily protect your stock brakes from near total destruction. Novice drivers may be easier on the brakes because their corner exit speeds are lower, their terminal speeds entering brake zones are therefore lower, and there's less kinetic energy being transferred into heat during a given stop. That said, novice track drivers also tend to stab wildly at the brakes, stay on the brakes too long, oscillate between on and off brake, and do all sorts of other things one would never expect! The end result can be some serious brake punishment. It's impossible to say that a novice driver will be fine on stock brake pads based on track experience alone.

Track layout
Long straights followed by tight turns mean your car is decelerating from a very high speed to a very low speed, creating a high energy stop. The distance between stops will also impact the heat retained in your brakes. If a particular track layout has a steady succession of medium straights and tight turns, your brakes don't have much time to cool between stops. That means heat will continually build. Flowing tracks with long sweepers are much easier on brakes (think Willow Springs (big track)). Look closely at the track(s) you'll be driving to determine how demanding they will be on your brakes.

Vehicle configuration/modification
All else held equal, more massive, faster cars place a greater strain on the brake system in a brake zone. An Audi Allroad will require a much larger rotor as a heat sink than a Miata. An FT86 falls somewhere between those two, but much more closely to a Miata. If you strip 200lbs. out of your car (easier to accelerate), have a quality coilover system (higher cornering speeds), and add 15hp (greater acceleration), you're placing less demand on your brakes in terms of mass, but you'll need to slow down from higher speeds when entering turns.

Tire choice
Tire choice is one of the single greatest factors in determining which brake setup will work for you on the track. The stickier the tire, the more brake you can use, and the more heat you will generate. More grip = more heat. If you're running the low grip OEM FT86 tires, or if it rains at an event, you won't be able to generate as much grip, and you won't tax your brakes as much.

So where does all of that leave us when upgrading your brakes for an HPDE or Time Trial? The critical point is, every modification you make to your car and the nut behind the wheel will change the demands on your brake system, and you must adjust accordingly. Just because you used a particular brake pad before, doesn't mean it will work again after you've installed your new turbo kit and Hoosiers. Chances are that after your 25th event, you'll be taxing your brakes very differently than you did during your first event. You'll be hitting higher speeds, entering and exiting corners faster and in a different way, and your car will likely have more grip and power than it did when you started (you'll also be much poorer, but likely happier ). If you typically run Limerock (a short track without many big braking zones), but decide to make a trip to Road America (a crazy fast track with huge brake demands), you need to reconsider how your brakes will be taxed. You must constantly evaluate the overall condition of your brake system, and not be afraid to try new brake setups as both you and your car evolve.

If you want to play it safe and not risk damage to the major components of your brake system, don't EVER drive an OEM pad on a road course. It may be more convenient and seem economical to run stock pads, but it will cost you time and money in the long run. There's also not much worse than wasted track time. When you're sitting in the pits watching your buddy rip down the front straight, and your stock pads are a steaming pile of dust lying inside your wheels, you'll be wishing you spent a couple hundred bucks and took the hour on Friday night to change your pads and bleed your fluid.

In the next installment I'll look at specific FT86 modifications for the track...TBC

[ultra]

What brake setup do you recommend for an experienced drver doing muktiple 30mi ute sessions of HPDE?

Which pads, and in your experience with car do you think that fluid and Ss brake lines are mandatory or optional? Also, what about ducting?

[yuli8466]

well, thank you

[JRitt]

What brake setup do you recommend for an experienced drver doing muktiple 30mi ute sessions of HPDE?

That remains to be seen as more and more drivers get out on the track. My goal with the first installment of the article was to get people thinking about how they use their car, and to make them aware of the OEM brakes' limitations.

We will be taking our project BRZ to the local track (Carolina Motorsports Park). After I get some wheel time out there, we should be able to see the deficiencies, and it will become more clear as to what the requirements will be depending on modifications, etc. (we plan to modify our BRZ significantly). All of that said, at minimum I'd recommend good front race pads and quality brake fluid if you are going to track your car. If you shoot me a PM we can discuss which specific pad compounds might fit your needs, and we will have SS brake lines available within the next two weeks or so.

Also, what about ducting?

We are developing a custom brake duct solution for the FT86. Ducts are a fantastic way to increase your brake system's cooling/heat capacity. Generally speaking, I typically recommend them fairly early in the brake upgrade process. That said, it looks like ducts may be a bit trickier on the FT86 they are on some other platforms. The windshield washer reservoir is right behind the front drivers' side fender liner, and there's not a lot of room to thread a duct between it and the fender liner. That means ducts may fall down the priority list a bit for people wanting to keep their wiper washers functional, rather than carrying around a bottle of Windex. We're going to see what we can do in that area.

Generally speaking though, ducts are an excellent idea. Forcing air into the center of the discs pays dividends in lowering the overall system temperatures. The cooling air lowers the disc temp, which lowers the pad temp, which lowers the heat transferring into the caliper pistons, which lowers the brake fluid temps, and so on. Also, when the discs are running cooler, less heat radiates to your wheel bearings, suspension ball joints, etc. So keeping brake temps down helps to prevent the degradation of other nearby components...not just the brakes.

In many cases, ducts are a relatively inexpensive solution that prevent you from having to spend more on a larger, more complete aftermarket brake system. They just have to be designed and implemented properly.

[acro]

I have a question to ask in some countries outside of the states the base version of the car comes with a slightly smaller front and rear rotor and the rear rotor is actually solid. Do u think that the rotors from the high end version will fit the base car.

Do they use the same calipers/brake pads

Will the rotor upgrade if possible make a difference

What do u think of ebc redstuff pads

[ultra]

i have the base model car here in Dubai and can comfirm that they're the same calipers as the MY 2008 WRX. They're a non-ventilated rotor design as opposed to the ventilated system on the higher spec cars, which also use different rear capilers.

Real PITA to find good rear pads for the 2008 WRX calipers. Hawk HP+ pads did fit on my car...just didn't like the pads much.

if I were doing the Sprint kit this would be my biggest issue - finding compatible front & rear pads for this setup.

[Dave-ROR]

Originally Posted by acro

I have a question to ask in some countries outside of the states the base version of the car comes with a slightly smaller front and rear rotor and the rear rotor is actually solid. Do u think that the rotors from the high end version will fit the base car.

Do they use the same calipers/brake pads

Will the rotor upgrade if possible make a difference

What do u think of ebc redstuff pads

Low spec rear brakes are WRX, high spec rear brakes are 2010+ LGT. Not 100% sure what the fronts on the low spec are from, but the high spec are WRX front brakes/rotors.

You can probably find used 2010 LGT rear brakes in a junkyard somewhere for cheap.

[JRitt]

[QUOTE]i have the base model car here in Dubai and can comfirm that they're the same calipers as the MY 2008 WRX. They're a non-ventilated rotor design as opposed to the ventilated system on the higher spec cars, which also use different rear capilers.

Real PITA to find good rear pads for the 2008 WRX calipers. Hawk HP+ pads did fit on my car...just didn't like the pads much.

if I were doing the Sprint kit this would be my biggest issue - finding compatible front & rear pads for this setup.
/[QUOTE]
What is the part number on the rear hawks you have? I can cross reference that part number and see what other optionswe have. Also, we sell every flavor of hawk for our Sprint kit.

[acro]

i got some more info. it seems as if stoptech makes a powerslot rotor for the 08 wrx that is vented 126.47029sr so ill probably get that. still need some info as to what the front rotors came from

Jritt. Do you sell powerslot or ebc brake products?

[JRitt]

Originally Posted by acro

i got some more info. it seems as if stoptech makes a powerslot rotor for the 08 wrx that is vented 126.47029sr so ill probably get that. still need some info as to what the front rotors came from

Jritt. Do you sell powerslot or ebc brake products?

Yes. I can get you power slot rotors. Contact me on Monday and ill see what we can do for you.
We do not sell any EBC products, but we do sell Hawk, AP Racing, Ferodo, CL Brakes, and Endless brake pads.

[CSG Mike]

Wow, how did I miss this guide?

Great post Jeff! I may have to plagiarize it.... :p

[JRitt]

Originally Posted by CSG Mike

Wow, how did I miss this guide?

Great post Jeff! I may have to plagiarize it.... :p

I don't care if you cut and paste, just give me some credit!

[JRitt]

Okay...we now have a substantial amount of additional input and data on the brake needs of the FT86 chassis since I wrote the original post back in June of last year. More specifically, there have been a ton of people who have taken their FT86 to the racetrack. I'm now adding a few more comments about that environment. I'm pulling some bits and pieces of posts I've made elsewhere on this forum to have them consolidated in one place.

There has been a lot of discussion on whether or not a big brake kit is needed for taking these cars on the track. After seeing all of the data and feedback over the past year, my opinion is 'maybe.' Whether or not you need a big brake kit will depend on all of the factors I listed in my original post under the HPDE section. It has been proven that some drivers, in some cars, on some tracks will exceed the limits of the OEM FT86 brake system fairly easily, and that includes a car with dedicated track pads and brake fluid. That said, there are plenty of others running track pads on the OEM setup without any significant issues.

Need and want are two different things however, and there are a lot of benefits to going with a big brake kit if you plan to keep your car and track it over the next couple of years. Check out this article I wrote on big brake system benefits you may not have considered. It talks about things like long-term running costs, wasted track time, confidence in the car, etc. At first glance, a big brake just seems like a big up-front expense. Once you think it through though, it makes a whole lot more sense. I'd say about 96% of my big brake kit customers who track their cars tell me, "I wish I had done this a long time ago."

From a financial perspective, if you're tracking your car heavily, a top quality BBK in the $2,000 range is almost a no-brainer. You buy it...beat it to death for the years you own the car, and will likely get at least $1k back for it on the used market when you sell the car. You can then drop your OEM brakes back on the car when you sell it, and they won't be thrashed. Brakes will be something you don't have to think or worry about during your years of tracking the car. You'll always have a good pedal, no heat issues, and total confidence in your brakes.

The alternative is throwing OEM replacement parts on the car more frequently...and at a greater cost (that's the worst part, that OEM pad shapes are more money than the shape for our kit). The OEM replacements burn up, and you get no return on them. You throw away the dead metal bits and start over every time. You also don't have worry-free brakes during that time period. You'll blow more time prepping, bleeding, swapping pads, and generally getting filthy at the track.

My estimate is that the average guy who tracks his car regularly will save enough money in two seasons to completely pay off a quality big brake system. That doesn't even include all the intangible costs of time and potential problems. That's just straight savings on pads, discs, fluid, and resale value. The lengthy list of system benefits is just gravy.

Hopefully that makes sense.

[AndyB]

I just found this site. The info here is awesome. My .02 on this subject as a HOD Coach, Lapsinc instructor, and Blackhawk Farms Raceway instructor, who has logged almost 2000 track miles on my stock daily driven FRS, is that you do need different pads for the track, but not necessarily any more than that. Most of the damage I have seen on this site from damaged rotors at the track are actually from the driver imo.

When tracking and using good pads you have to manage your temps by getting on the brakes and then getting off of them. Duh, I know. Seriously, almost all of my students brake to lightly, too long. All of the energy of slowing the car turns to heat, but if you can do it quickly it focuses the heat on the surface of the pad and the surface of the rotor. These will immediately start to cool when you get off the brakes. Dragging 50' longer and lighter allows the heat to "soak" deeper into the rotor and through the pad material into the boat anchor cast iron calipers. Once everything is glowing hot from heat soak, your doomed.

Again this is my opinion with my car, but I have been able to absolutely harass Boss mustangs and Caymens on the track with stock tires and stock brakes with Carbotech xp8 pads on my FRS. Better tires would mean I could get on the brakes harder for a shorter period of time, thus reducing temps. I will only be thinking of BBK when I find another 50hp