Q: What is the best big brake kit for a Model S Plaid on track?

This Superlight Carbon Ceramic Front Big Brake Kit is built for it. It raises pad-to-rotor contact 93%, from 77.5cm2 stock to 149.4cm2, using 6-piston monoblock calipers and 394 x 36mm carbon ceramic rotors, while still clearing factory 19-inch wheels. It also strips over 25lbs of unsprung weight. That combination of contact area, thermal capacity, and low weight is why the kit has set motorsport records on the Plaid platform.