StopTech C-43 RACE Big Brake Kit with Floating Rotors

I am an avid track day enthusiast and run between 3000-5000 track miles per year on my factory equipped Brembo ND1 with cup car cooling ducts on BFG race slicks; it's a dedicated track only car. Over the years I have moved through most of the Hawk pad selection, autocross, DTC-60 and finally the DTC-70s. The DTC-60s would overheat and gas off creating a very unpredictable situation from turn to turn. The DTC-70s solved the inconsistencies of the -60 compound albeit with a significant increase in heat load to the entire system. The -70s would generate enough heat that the Centric rotors would show cracking in just one weekend and be cracked from top to bottom by the second weekend. Additionally, Motul 600 was no longer sufficient and I also earned the famous "Brownbo" badge of honor. The reality is, I was at the limit for that system and not in a place that I wanted to be with laser focus on safety.

Enter the Stoptech C-43 kit with SR33 pads and a giant, extra thick free floating rotor. This setup was recommended by our track day organizer after installing on one of their NC cars. I called Brian Goodwin and he seconded that I would love this setup and it would ultimately drop lap times. Brian has never steered me wrong or sold me on something that didn't make the car better and ultimately faster.

Pros:

Installation was easy.

I didn't think it would be possible but my braking distances DECREASED between 50' and 100' with no ABS activation. The volume (piston size) of the C43 caliper has been so carefully selected that the electronic bias is even better than stock. SR33 pads up front, DTC-60 pads on the factory rear.

The pads are $100 cheaper than the Hawk DTC-70s and over twice as thick. Furthermore, after 300 track miles the pad wear is imperceptible and the rotors show absolutely no signs of abuse. The offset piston sizes are exact in that pad wear was perfectly even from top to bottom, this was a problem on the Brembos with the -70s.

I installed Brembo/AP Racing thermal labels to each caliper piston (as close to the pad as I could get) and only the right front got hot enough to trigger the lowest range of the label, 300*F. One could literally run Dot 3 or 4 in this setup and be absolutely fine.

As I had the system opened I decided to replace the master cylinder and fill with Endless 650 (again, this was not necessary) and the pedal was noticeably stiffer. The pedal feel is absolutely incredible. You can modulate your trail braking with light adjustments and the pedal doesn't sink anywhere like it did with the factory Brembos, the system is incredibly precise.

The bedding instructions were followed, 10 stops 60-10 and 4 80-10 with no issues transferring a nice layer to the rotor. No clumping at all. The SR33 compound is very user friendly.

I don't believe one would need brake cooling ducts with this setup.

Cons:

I second Brian's opinion on not installing this setup on a street car. The free floating rotors are very noisy and the pads squeal like a real race car in the pits, after all it is a real race car brake system.

Installation instructions were for an NA/NB Miata. However, there are two identical caliper brackets (laser etched with which direction to mount towards the rotor) and the hoses and calipers had stickers indicating left and right. The rotors are bi-directional, non-curved vanes.

The stock BBS wheels will not fit over this caliper, not even close. The Rays Global Cup Wheels fit with only 1mm of space so I opted for the longer ARP studs and had to run Brian's 3mm spacer. Running the spacer means you lose the hub-centric alignment of the wheels to the hubs. No big deal, just torque up in increments.

-- Rich H. ( MX5 ND1 ) November 2019