We are asked this question multiple times a day and for good reason. There are several variables involved in choosing a proper brake compound. G-LOC offers 8 different Compounds in their product line range so choosing the correct compound for YOUR specific application can appear daunting. We are going to cover the basics so you can answer the questions yourself.
1. Obviously Year/Make/Model/Specific Brake System i.e. Brembo 4 piston, 6 Piston, Iron Rotors, Carbon Rotors etc. If it has a Non-OEM Brake System on it, knowing the caliper model or pad shape will be information you need to know along with pad thickness if it is a race caliper that allows endurance pads that are typically in the 25mm range.
2. What is the intended use? Daily Driving, Street Driving/AutoCross, Street Driving/Track Day, "It sits in the garage and I drive it to my track-day", "I trailer it to the track" Time Trials, Racing.
3. What are YOUR Goals? "I can't stand the brake dust and noise" or "The factory pads lasted one day at my last event and now I have a brake pulsation"
4. What have you done to your car? What tire - specifically, suspension - stock or adjustable coilovers with full adjustments, brake fluid, brake cooling.
To answer these questions honestly and realistically helps in successfully choosing the proper compound. Lets run through a couple of examples.
1. 2017 Shelby GT350
2. I drive it mostly on the street.
3. The brake dust is horrible, constantly cleaning my wheels!
4. Stock because it's amazing.
In this case G-LOC's GS-1 Compound would be the perfect choice. You would not compromise braking performance on the street, the compound is low noise, low dust with a very high bite that will still give you factory level braking on the street. We will let you in on a secret, all brake pads dust otherwise they would not stop the car. G-LOC compounds use materials that do not attack finishes so typically the dust just wipes off. The GS-1 compounds have a very low rotor wear rate, known as "rotor friendly". This prevents metal from the rotor from etching into wheel finishes.
1. 2017 Shelby GT350
2. I drive it occasionally but mostly do track events
3. The stock pads are ok but I find near the end of the session they begin to fade and I'm on my third set of pads. I am more comfortable in the car and I find myself pushing the braking every session. I think I need something with more bite and something that won't fade. I'm used to brake dust but want something that will still work on the street.
4. Stock MPSS's. I do not plan on changing to a track tire.
In this case we can go in two different directions. The R12 Compound offers an extremely high bite, a large temperature operating range, it can be driven on the street and in this application would be a great starting point for someone to transition to a race compound pad. It will make noise and dust but it will shorten braking distances and used properly, not fade.
You could also go to an R16 compound which is going to have a higher level of bite and temperature capability than the R12 but while it can be driven on the street it is best for the "I drive my car to the track, most of the time it is strictly a track toy" person.
When you begin to look into track/racing brake compounds you need to look at balancing brake bias. What we mean by this, using the above GT350; a heavy car with huge speed potential, grip and massive brakes you need to balance the braking front and rear. Most cars are typically biased towards the front because under braking the front tires have most of the grip. The rear typically gets light so in a modern car with ABS the computer does most of that work for you. When you install a track/race compound on the front you will change this bias. The higher friction level of the pad will move more brake bias up front. If you leave the stock rear pads in place and run an R12 or R16 up front the front brakes will begin to do all the braking. This leads to very hot front brakes, high pad wear and sometimes a very unstable experience in a heavy braking zone. Matching the rear compound to maintain the factory brake bias will make the car faster, the brakes will maintain temperature and the pads will wear much longer.
How do you match a rear compound to your fronts? Generally speaking, choose a compound one or two steps down from the front. Examples from above R12 front with an R10 rear. R16 front with an R12 rear. One of the advantages with the G-LOC pad compound choices is you can adjust this to your driving style and car set-up. You can add more rear pad if you have rear downforce or trail brake. This will give you more rear bite. If you find your style of trail braking is inducing too much oversteer you can also run less rear pad. There are many combinations you can run R12/R10, R12/R12, R16/R12, R16/R10.
Lets look at a few other scenarios...
1. 2014 Mustang GT with Track Pack - 4 Piston Brembo's
3. I dream of orange cones in my sleep.
4. All sorts of camber and sticky tires
The best choice for pure Autocross is the R6 front and back. The R6 is G-LOC's Autocross pad of choice. On Mustangs you can also run R8's. If you mostly chase cones but are thinking about trying a road course for the first time R8's will work as long as you drive within the parameters of the compound.
1. Miata - Lighter Momentum Cars
2. Street/Track Day
3. I like passing Mustangs in the turns, but I drive it everyday.
In this case you would want to start with an R10 up front balance with an R8 in the rear. The pads are mild enough on the street but still work very well on track.
1. S550 Mustang GT with the Performance Package/ 6th Gen Camaro
3. I don't record my laptimes and I don't want to swap pads..ever. I have had race cars in the past, very experienced but this is just to have fun with and I understand how braking works.
4 Stock, it is really a good chassis.
This is pretty universal for most cars. R10 Fronts with R8/R10 rears. This is a very contested area because it requires restraint to some extent. If you go this route and then decide to put on some used slicks you picked up from a race team it may not turn out how you planned. Mustangs are heavy cars, if you have an instructor you will be stopping 4000 pounds for 20-30 minutes at a time. If you use these properly they will work very well for you. I personally run these on our S550. I have 6 track days on them and they still look new. I have reasonable expectations and have pushed the limits of them from time to time. Typically I find the limits of the street tire before the pad compound.
1. S550 Mustang GT/S197 Mustang GT/5th-6th Gen Camaro
2. I drive to the track.
3. I need to beat everyone else
4. I've ruined a perfectly good street car. Full suspension, roll bar, harness, seats, brake cooling and 'street tires' that last about 2 days because they are basically slicks.
R16/R12 but you should change to R18's...when you get to the track or just buy a car trailer.
In the same scenario above with any Mustang/Camaro/Corvette that is trailered to the track and not driven on the street and runs a Rival/Hoosier/Race Team Scrub Slick should always be on an R18/R12 combination. Even the GT350 on the Cup2 tire is so fast it can take advantage of the R18 friction levels. And now a message from our Lawyers: R18's are not to be driven on the street. They require heat to begin working plus they will just wear out pads and rotors quickly.
Last Example: I want to drive my Mustang everyday to work which is a 100 mile round trip. On weekends I want to run Watkins Glen, what Compound do you suggest?
In this case; which ends up being the case for most of our Customers who need to pay for their track days by driving the race car to work, you need to swap pads. There is no magical pad that will do this, many manufacturers will claim it, it is not based in reality. Pads sold to operate in two polar opposite environments will be a big steaming pile of compromises. G-LOC is not a marketing company, they are a hands on brake pad manufacturer.
For true weekend warriors that need to get to work on Monday but want to win the HPDE trophy need to use a pad for each goal. GS-1's during the week and then swap on the track pads either the night before or at the track when you are bolting on your tires. While the initial investment is higher, the savings will be noticed in a short period of time. Running a more expensive trackpad only on the track greatly reduces wear. Running a street pad on the street greatly increases your sanity from a quiet pad. G-LOC compounds are all compatible with each other. You can run any compound on the same brake rotors. Swap the pads in and go, no bedding, sanding, separate track rotors etc.