Originally Posted by travislambert
A word of caution...
When you mess with brakes you're asking for trouble. I have quite a bit of insight into what goes into the calibration of the braking system, and I'm telling you guys, be careful. You will quickly create more problems than you will solve by using aftermarket brake kits. Essex simply throws AP Racing kits together. Their engineering isn't the greatest, and I know from first-hand experience their kits can and do cause issues on the Camaro.
I purchased the original 390mm kit (plus the rear kit) for the Camaro with DS1.11 pads. Prior to that I was running stock calipers and rotors with the DS1.11 pads. Comparing the data between the two, the initial bite (decel) was better with the AP kit, but almost immediately after the initial bite the decel on the stock brakes would outperform the AP brakes. In the data I found that I was braking later and had better overall stopping power with the stock brakes. (When you think about what's going on with the heat and the mass difference between the two, it becomes obvious that this will be the result.) Sure, there is a weight difference, but I'll take better brakes that can handle more heat any day of the week. Imagine for a moment that the AP brake kit was stock and then you paid $11k+ for the Brembo kit. As you install the big and heavy Brembo brake kit, you'd likely be proud of how much more braking power you'll have and how much more heat it can handle.
I sent the data to ESSEX along with pictures of the pads, rings, etc., and to their credit, they responded by updating the 390mm kit to one that uses heavier rings and thicker pads. One new problem is they don't offer the new pads in anything but the DS3.12 compound, which I have found to not work as well on the Camaro as the DS1.11.
Thankfully, ESSEX did allow me to return the kit I had purchased. I returned my car to stock brakes, but since then I have driven a friend's ZL1 1LE with the revised AP Racing 390mm kit. Unfortunately, I don't have data from this car, but I still was not impressed. I drive in Sport 1 which the computer uses the brakes for stability control. With aftermarket brakes, this simply no longer works correctly. The stability is much worse. After driving this ZL1 1LE then returning to my car with stock brakes, my decision to go back to stock brakes was completely validated.
One positive of the AP kit is the brake pedal travel is greatly reduced. The downside is, the software expects to see more travel when braking hard. If you have the A10, this can lead to the transmission exiting performance shift mode in braking zones. A friend of mine actually had this issue and it took a lot of work by the GM engineers to finally figure out the aftermarket brake kit was the issue. The automatic transmissions have fault detection that compares the brake pedal position with expected max decel rates, etc. When the observed sensor values fall outside of the expected range, the software then assumes there is a transmission issue (possibly causing the rear wheels to drag). The response is to exit performance shift mode, shift into neutral, and then after a brief pause, retry. Keep in mind, it's not that the brakes are exceeding the decel of the stock brakes. It's the difference in brake pedal travel that's at the root of the issue. The AP kit pedal travel is reduced and at lower pedal travel, the allowed rates of decel before the transmission faults is also lower. Ideally, this software check would be pressure-based, but it isn't. It's based on pedal position. When you use brakes not designed with the car, this is the type of gremlins you can expect.
Not to sh*t in anyone's Cheerios here, but I challenge you guys singing the praises of this AP kit to do an actual A->B test vs stock hardware. I think you'll be surprised at the data. Unfortunately, most guys declare success anytime they spend money because it's hard to admit sometimes that spending $11k+ was a mistake. Mentally, you might even think it's better. I bet the braking performance data tells a different story though.
I see someone mentioned the Racing Brake stainless vented piston kit. If anyone goes down this road, compare the piston diameters with a caliper before installing. It took 3 attempts for the folks at Racing Brake to send pistons that were within normal tolerances. In the end, I really don't know that it was worth the hassle for the pistons. I would assume they are better, but the difference in fade, pad life, etc. wasn't perceptible. I do however really like their high temperature dust boots. Those have held up nicely compared to the OEM boots.
My advice is to be happy with the stock brakes. They work amazingly well and are engineered to work correctly with the ABS, ESC, transmission fault detection, etc.. If you absolutely have to upgrade, get the air deflectors from the CT5-V Blackwing. Those help tremendously. For brake pads, do yourself a favor and use DS1.11 front and rear. They are a very close compound to the HP1000 so the electronics stay happy and you get improved brake performance and pad life.
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