Going skydiving? You’ll need a parachute. After all, it should make leaping from that airplane a bit more survivable.
Of course, not all parachutes are the same, and there’s more to them than different colors. Parachutes come in a variety of airfoil shapes and sizes, each one suited to a particular jumper and situation. While they’re all designed to serve the same basic purpose, there are subtle differences in the huge range of offerings.
You can think of brake pads in a similar way. Although there are countless varieties of pads available today, they all do the same thing: create friction to slow a car. Of course, the faster you go on track, the more important it becomes to have adequate stopping power.
High-performance brake pads are a crucial component for a car that sees open track time or race use. Not only are these top-tier pads more resistant to fade, but they can also have a higher coefficient of friction for quicker stops. Of course, that improved pad friction will only help if the tires are good enough to take advantage of the increased brake torque.
But what about autocross use? Are high-performance pads an advantage when battling the cones? While the brakes usually don’t get smoking hot during a 60-second autocross run, they can still see elevated temperatures, especially if there’s a co-driver adding a second dose of abuse.
More importantly, most of us autocross on sticker-than-stock tires. Can increases in brake pad performance help those grippy tires yield faster times?
To compare these theories against the stopwatch, we pressed our 2010 Mazda MX-5 project car back into service. To see how brake pads impact autocross performance, we tested four different brake compounds: the OE Mazda pad, the street-performance Hawk HPS, the track-worthy Hawk HP Plus and the race-ready Hawk DTC-60.
Our Mazda’s KW coil-over suspension and fat Dunlop Direzza Sport Z1 Star Spec tires make it a great platform for evaluating brake pads. The car is easy to drive, and we’ve found the Dunlops to be very consistent throughout the day and over a wide range of temperatures.
Tire Rack’s John Rogers and Chris Harvey served as our test pilots for this exercise. They’ve logged thousands of laps on Tire Rack’s own test course—which would again serve as our test lab—and have a considerable amount of seat time in the MX-5 project. A Race Technology DL1 data logger handled the data acquisition for the track work, while a Vericom VC2000 recorded the 60-to-zero stopping distances.
We tested each of the four pad compounds on a separate set of brand-new Centric rotors. By testing each pad with fresh rotors, we eliminated the possibility of contamination between samples.
Each set of pads was bedded in using the manufacturer’s recommended procedure. This included several stops from speed plus an appropriate cooldown period between sessions. The pads and rotors were then removed from the car and set aside until our day of testing.
We started with the stock Mazda pads and then, in order, went on to the HPS, HP Plus and DTC-60 compounds. We finished off the day by retesting the original pads; this is a great way to make sure the surface and conditions have remained consistent.
Each set of pads also went through the same test sequence, starting with four two-lap runs. Immediately after logging those laps, we did five 60-to-zero stops on a section of level asphalt.
