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Supermiata Boxmount BBK F88 11.75 x 1.25 90-05 MX5

From: $959.00

Product Description

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Boxmount™ Big Brake kit – Front

11.75 x 1.125″ rotor – AFCO F88 (Stoptech ST43) caliper

 Limited supply! 

 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

Why AFCO F88?
The AFCO F88 is a discontinued private label Stoptech ST43 caliper ($450 each originally) made just for AFCO. We also stock rebuild kits for the F88. We love the Wilwood Superlite caliper in our BX11.75 with the thick wall 1.1″ directional rotor but the F88 kit allows a much less expensive 1.25″ Wilwood 160-2898 & 9 directional rotor which are available through many source for around $65 each. The F88 also features staggered pistons to reduce uneven pad wear and uses the same enormous 7420 pad (20mm) as the Superlite. The Wilwood Superlite version of this kit is a bit more compact so it requires less space inside the wheel.

CLICK HERE for caliper rebuild kits

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.

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.

No Spacers

15×9 Countergram
15×9 Hexagram
15×9 dekagram
15×9 Gen 5 6UL (2023+)
15×9.5 6UL
15×9.5 Freeform
15×10 6UL
15×10 Dekagram
15×10 Jongbloed
15×10 KE Motorsports

Wheel clearance template


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

  • AFCO F88 forged 4 piston aluminum front calipers, gray anodized
  • Staggered 32/36mm pistons, aluminum
  • 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




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