Sometimes the point of a particular exercise isn't as clear as one might think. Take, for example, installing a big-brake kit onto a newer Camaro. Many may think the main purpose is to shorten the distance needed to bring the car to a halt, but that's not the number one objective. Let's face it; new cars stop pretty damn well already. With ABS and modern components, GM put a lot of thought into these systems to make sure the car can "panic stop" in short order.
So, then, what's the point of spending big bucks upgrading a brake system? The answer is "repeatability." Sure, the new brake system will shave a few feet off the stopping distance, but the big payoff is that the new brakes will pull off repeated heavy braking over and over while better resisting brake fade. GM didn't set out to build race-quality brakes suitable for hitting the local road course. As such, the factory parts tend to degrade in performance quickly when being subjected to heavy punishment. This is where aftermarket companies like Wilwood Disc Brakes come into the equation.
Brakes work by converting forward momentum into heat energy, and this heat needs to be properly controlled. It needs to be insolated from the brake fluid and, most importantly, dissipated quickly from the rotors. This is where the larger mass and curved-vane arrangement of an aftermarket rotor really pays off. More mass means the rotor can hold more heat in addition to being stronger, while the curved design of the vanes helps move air through the rotor more efficiently than the less-expensive-to-produce factory rotors with straight vanes. Today, drilled rotors are more for looks, but slots still play a role by providing smoother pad engagement and improving the thermal balance across the rotor. The larger rotor diameter also moves the caliper away from the hub, thus increasing its leverage effect. Now, one might think that all this rotating weight might hurt other performance areas, and to some degree it does, but the benefits for a Camaro that needs to decelerate as well as accelerate, outweigh the downsides. Wilwood helps keep the overall weight down by employing a two-piece rotor with a center section, called a hat, composed of lightweight aluminum. Still, a bigger iron rotor will always be heavier because physics says it needs to be.
Another area where braking performance is gained is in caliper design. The factory brakes on our '01 Z28 use twin-piston floating calipers up front and single-piston versions in the rear. The aftermarket switches this over to a radial-mounted fixed caliper. The revised mounting simplifies the installation and gives two planes of adjustment so the caliper can be precisely aligned over the rotor. The caliper itself is far stronger than the factory unit to better resist flexing, which can degrade performance. The pistons are constructed of stainless steel to better insulate the brake fluid from the massive amounts of heat generated during repeated heavy braking. Piston area, pad volume, and a host of other aspects are optimized for doing one thing: quickly bleeding off speed over and over again. Add in brake fluid that's designed to operate at higher temperatures, along with the right brake pads, and the end result is a brake system that will be going strong long after the factory parts would have given up the struggle.
Black Betty, our '01 Z28 is first a street car, but we also love to run in various autocross and road course events. We found the road course laps were especially hard on our stock brakes and editor Licata reported they were AWOL after only one lap. To fix this fade, we took the fourth-gen to Wilwood's installation center for a set of their badass binders.
At the Track
It doesn't take a rocket scientist to see the new brakes look killer behind our new 18-inch wheels, but the word "Performers" is in our title for a reason, so we booked some time at our favorite test site in El Toro.
We wanted an "apples to apples" comparison, so our before testing was done with the Global West suspension, NewGen wheels, and Nitto NT05 tires installed. Our best 60-0 mph stopping distance was 119.85 feet. The problem was that, after two or three hard ABS-inducing stops, the stock brakes felt spongy and started to fade. This caused the stopping distances to gradually increase.
After installing the new Wilwood units, we once again hit the test track. This time we were rewarded with a best distance of 109.62 feet. But more important than knocking 10 feet off the distance, the new brakes showed no signs of fade or fatigue even after a dozen all-out bouts of brake abuse.
Since then, Licata has logged hundreds of street miles and the brakes continue to work great with no brake squeal and minimal dusting. To us, that's the best of both worlds. He won't have any excuse for not turning in great lap times next time we hit a road course.