The factory brakes served...
The factory brakes served our Goat for 55,000 miles before we had the 12.6-inch rotors resurfaced. By the time we were ready to begin the swap, the brake pulsation was beginning to come back.
We had no trouble installing the brake parts and it's something you can do easily in your driveway in a day.
Once they were installed, we performed the proper bed-in procedure for the pads (we'll cover this in Part II) before we drove home in traffic. Our first impression was the new, great response from the brakes. They really bite now and made a large improvement at the autocross. There was no noticeable fade, even after repeated heavy stops around the track. The ABS system was kept in check and worked well at controlling the more powerful brakes.
Though easy to install, it took nearly 40 photos and captions to show the parts, the install, and the testing, so this story will be presented in two parts. We'll get into the descriptions and the install of the front brakes in Part I and finish up in Part II with the rear brakes and the testing.
Note the black rubber-brake...
Note the black rubber-brake hose and the factory PBR two-piston caliper assembly.
The Long Debate: Slotted Vs. Drilled Rotors
All over the internet and at every track, we're sure you've heard the debate about which is better: slotted or drilled. We were sure to bring this topic up with Mark Joseph and John Poulakis at DBA. When our brakes were suggested to us for our application, we weren't the least-bit surprised that they were slotted only.
According to John, slotted is best suited for heavy-duty conditions with high thermal loads. The slots clean the pad face while helping with the outgassing of the pads, and provide more even pad wear with reduced glazing. Drilled or drilled-and-slotted are best suited for improved braking performance under normal driving conditions. "They're not recommended for extreme conditions where there are high thermal loads," he says.
In high-heat conditions, drilled rotors tend to crack or "spider" around the holes. They also reduce the amount of surface area for the heat to dissipate, diminishing their cooling ability. Since our GTO will see heavy autocross and open-track time, it's safe to say that this is a heavy-duty role that will generate a lot of heat. We won't have to worry about any cracks forming and our pad surface will continually be cleaned.
There are two 15mm bolts that...
There are two 15mm bolts that hold the caliper to the caliper bracket. Once they are removed, the caliper can be lifted off.
A place was located to support...
A place was located to support the caliper before the brake hose was slid free from its bracket. Never support the caliper by the brake hose, especially if you plan on reusing the factory rubber ones.
The PBR calipers are the floating...
The PBR calipers are the floating type, meaning they only apply pressure from one side and the caliper actually slides to contact the rotor on both sides.
The stock rotor (left) is...
The stock rotor (left) is approximately 6 pounds heavier than the DBA rotor, which is a significant difference. The braking surface was cleaned with brake-parts cleaner before the new rotors were installed, and care was taken not to remove the thermal paint on the edge of each rotor. We'll discuss the importance of the thermal paint in Part II.
The two 21mm bolts that hold...
The two 21mm bolts that hold the caliper bracket on were removed in order to free up pads and gain full access to the rotor. A rubber mallet aided in convincing the rotor to come off. The pads were still well within spec for thickness.
To remove the caliper, the...
To remove the caliper, the brake hose and line had to come off first. A 10mm line wrench was employed. All painted surfaces in the general area were covered to protect them against any dripping brake fluid, as it will damage the finish.