Hi Everyone,
I hope you're having a great Friday! I appreciate the kind words. I can assure you that our solution will be fully tested on the racetrack as all of our parts are. We don't design parts in isolation, we always fit the parts to the car and evaluate and optimize on the track. That's part of what we love doing the most and I think critically important.
The rotors are made by Girodisc - so that means USA-made with top quality materials and experience. These guys are some of the best in the business and we're super proud to be working with them!
We opted to go for the 400mm rather than 380mm because it will be very rare for anyone to use 19" wheels who are serious about performance, and for the tiny additional cost, it makes more sense to fit the largest rotor possible as we're talking about a 1000hp vehicle here! We'd also like to add additional thickness to the disc but need to be careful as the caliper wasn't designed for a wide rotor and some rubbing after thermal expansion could be possible if we push our luck too much.
Through our testing we've also discovered that the current calibration of the brakes has too much rear bias, so a larger front rotor will help with that. As you all know, the more grip you produce, the more forward weight transfer the vehicle experiences, and the more front bias is required to balance that out. So it's win-win to fit a larger front disc in regards to brake bias as well.
The rear rotors will be bolt-on. Here are a few pictures of the front rotors if you haven't seen the other thread.
These rotors paired with proper pads, lines, and fluid should really make a staggering difference to the braking feel and endurance - so let's not give up on the car over that!
It's also worth mentioning WHY upgrading rotors is so significant. I think many imagine the caliper as being the most important component of the braking system, but in fact, as long as you have sufficient pad area, it is the rotor that is the most important.
The rotor is the single component that controls how much heat the system can remove.
If you look at the above picture you can see how much wider the air slot is than the original rotor, how open the inlet to the rotor vanes are compared to the shrouded OE rotor, and of course the main point - the fact that these rotors are directional and work as an air pump to flow a massive amount of air through the disc. The faster you go, the more airflow and the more cooling.
This is what ultimately allows the brake system to run cooler, and thus give you a more consistent pedal over more than one or two stops, and prevents pad fade. It also allows some to run a less aggressive pad, meaning one pad can work for street and track driving. Although in the case of the Plaid, I'm pretty confident high temp pads will still be required if you're hitting the track - sorry!
Using IR brake temperature sensors, we did a comparison of a few hard stops using OEM Model 3 brakes compared to a larger (365 instead of 320) rotor for the non-performance Model 3. You can see how much cooler the brakes ran with the upgraded rotors, and how much faster they cooled off: