Track Day on AP Racing 9660 372mm Brake Kit 

I finally got the chance to get the new AP Racing brake kit on track at Palmer Motorsports Park. I ran Ferodo DS1.11 pads up front with Hawk DT60 pads in the OEM STI Brembo rear calipers. Although I routinely glazed the DS1.11s with my previous 325mm brake kit, I figured the compound would hold up better with the larger brake kit. However, I managed to glaze the larger pads as well and the rotor temperature paint indicated temperatures over 800 degrees Celsius. Bigger brakes did not magically fix my problem. The primarily culprit is likely me. I’m likely over braking and driving temps up more than needed. Add to that the STI tips the scale with driver at 3400 lbs and Palmer is pretty hard on brakes. Additionally, despite my efforts, I could have done a better job bedding the pads in.

Despite my flaws, the 9660 372 mm kit was always dependable. There was some loss of brake effectiveness when the pads glazed, but they never demonstrated the scary fade that the smaller kit did. The initial bite is much stronger and the limiting factor is the tires. Moving forward I’ll work on my braking, do better bed ins, and try a compound that can handle a little more heat like the DS 3.12 or Hawk DT70. Flat Irons Tunning did a great write up on brake pad selection here https://www.flatironstuning.com/blog/how-to-pick-a-brake-pad.

Below is the video of my fastest lap on the new brake kit and a a line graph comparing it too my previous fastest lap. I was about a second off my previous time largely due to lack of proficiency and it was about 20 degrees warmer, so the car was a little down on power. Even after I glazed the pads, you can see that the 372 mm kit has better initial braking force and deceleration compared to the smaller 325 mm kit.