Boxmount™ Big Brake kit – Front

11.75 x 1.25″ rotor – Wilwood Superlite Caliper

 Patented Boxmount technology reduces lug mount deflection resulting in a firmer pedal and more predictable braking. The boxmount also allows much greater cooling airflow without sacrificing rigidity. The best cooling and thermal mass of any NA/NB brake system in the world. Works with all years ABS systems. Complete kit, all mounting hardware included. Duct kit optional

Comparing our kit to others
A few things to look for in a competition ready brake kit for the Miata. Rotor mass matters. Our kit uses a fat 1.25″ thick rotor. Most others use a .810. You will save overall system weight with the alloy hat and caliper. The rotor needs to have as much thermal mass as possible. That’s your “heat sink”. Some kits use a radial mount caliper adapted to your OEM lug mount spindle. Unfortunately, this type of hybrid mount is not as rigid as a radial mount spindle and is actually less rigid than a plain lug mount caliper. Our patented Boxmount system is stiffer than a hybrid radial caliper to lug mount spindle system. We use the beefy forged Superlite caliper specifically for its 7420 pad which is a whopping 2.4x larger than the OEM pad. Most other kits use the much smaller 7812, 7816 or 6712 pad. No other kit has a fully integrated 3″ duct kit. Anything smaller than 3″ doesn’t work. We know because we tested that too.

Boxmount & ducting
Not all BBK’s are created equal. Though 15 years of sprint, time attack and endurance racing (and many victories), we have learned a lot about high performance brake system requirements. Many will focus simply on maximum rotor diameter and lightest weight, but this approach ignores important details. Even small OEM brakes can easily lock Hoosiers once. Increased thermal capacity and mass is needed to sustain repeated maximum braking events. The BX1175 was designed with a focus on thermal capacity, pad life and brake feel. The rotors were chosen not only for the diameter, but for overall thermal capacity. Thick-wall, directional-vane friction rings are now standard. Increased thermal capacity combined with the large pad thickness decreases fade and knock back while greatly improving the life of the pads. The Boxmount brackets decrease deflection, improving feel and consistency under braking. Note that radial mount kits for the Miata must use a cantilevered and unsupported adapter bracket to mate to the lugs on your spindle. Boxmount brackets are actually stiffer than a converted radial caliper assembly. Whether you’re racing the full WRL series or just enjoying your well-built track car on the weekend, the BX1175 provides the best braking performance.

Which rotor?
The 9.6 lb Wilwood economy rotor option is recommended for autocross or cars under 170whp. For track use or cars over 170whp, the 11.4 lb Supermiata HD directional rotor is required. Do not make the mistake of choosing the lightweight rotor option for your engine swapped or forced induction track car 🙂

Use the drop-down menu above to add it to your BX1175 order for a 5% discount on the ducts. Learn more about the duct kit here.

WHEEL FITMENT INFORMATION
No Spacers
15×9 Gen 5 6UL (2024+)
15×9.5 6UL
15×9.5 Freeform
15×10 6UL
15×10 Dekagram
15×10 & 11 Jongbloed
15×10 & 11 KE Motorsports

5MM SPACER REQUIRED
15×9 Konig Heliogram

Wheel clearance template

How to use a BBK Wheel Clearance Template (YouTube Short)

INSTALLATION INSTRUCTIONS

See our brake system FAQ for more information on choosing brake system components for your Miata

• Wilwood Superlite forged 4 piston aluminum front calipers, gray anodized
• Billet CNC 6061 T06 aluminum hats, hub centric
• 11.75″ x 1.25 Left & Right Directional Vane Rotors
• Braided stainless, orange hoses
• Billet CNC aluminum brackets, orange anodized
• Steel Boxmount braces
• All hardware and instructions included
• Your choice of 7420 plate pads (20mm), or choose to omit pads
• (Optional) Duct kit

Need help deciding on the compounds, give us a call or email

Compound guide