Girodisc A1-322 BMW G8X M3, M4 Front Iron Rotor Conversion
A1-322
These GiroDisc 2-piece rotors are a direct replacement for the 400mm carbon ceramic front rotors on the BMW G8X M3 & M4. Our 2-piece, fully floating assemblies utilize the factory calipers and require no modifications other than switching the rotors and pads. These rotors use the factory iron pad shape with the carbon ceramic calipers. Please contact us if you need help finding pads.
The rotor rings are machined from a proprietary casting made of high-carbon iron formulated to GiroDisc’s specifications. This superior metallurgy results in a rotor that holds up better, and the 72 curved vanes act as a centrifugal pump pulling air in through the hub to effectively cool the rotors under hard use. The 2-piece design means a reusable hat which can be attached to new rings (part number D1-220) when they need to be replaced.
All major components including the hats, rotor rings, and drive pins are manufactured in-house at our facility in Bellingham, WA from domestically sourced materials. The hat is made from 6061-T6 aluminum and coated in a black anodize finish. The drive pins are made from a high-strength steel alloy and cadmium-plated for corrosion resistance. All rotors are assembled with spring clips and Belleville washers for race-ready float while also being street-friendly with no noise from loose hardware.
The minimum thickness at which we recommend replacing these rings is 34mm. We also recommend replacing them if a crack leads to the edge of the ring.
Sold and priced per pair.
The rotor rings are machined from a proprietary casting made of high-carbon iron formulated to GiroDisc’s specifications. This superior metallurgy results in a rotor that holds up better, and the 72 curved vanes act as a centrifugal pump pulling air in through the hub to effectively cool the rotors under hard use. The 2-piece design means a reusable hat which can be attached to new rings (part number D1-220) when they need to be replaced.
All major components including the hats, rotor rings, and drive pins are manufactured in-house at our facility in Bellingham, WA from domestically sourced materials. The hat is made from 6061-T6 aluminum and coated in a black anodize finish. The drive pins are made from a high-strength steel alloy and cadmium-plated for corrosion resistance. All rotors are assembled with spring clips and Belleville washers for race-ready float while also being street-friendly with no noise from loose hardware.
The minimum thickness at which we recommend replacing these rings is 34mm. We also recommend replacing them if a crack leads to the edge of the ring.
Sold and priced per pair.
Pricing:
$1,450.00
Description
The disc is made from cast iron, constructed in the USA and is made to the same specification and material as used by professional racing organizations.It is a curved vane design, developed in racing to act as a centrifugal pump to force cooling air through the disc.
The rotor and hat have a floating mount system, which utilizes 8 or 10 high strength alloy steel drive pins, manufactured by Girodisc in the USA to our own specifications and cadmium plated for a long lasting corrosion resistance. These pins take the load from braking actions while maintaining the axial and radial float between the hat and disc. The pins are secured by grade 12 cap screws with hardened washers. In order to keep the rotors from making noise when cold, the pins are mounted with anti-noise spring washers on the rotor side which allow the rotor to grow with heat expansion but eliminate the rattle and noise associated with floating rotors. This float also allows the rotor to self center between the pads.
Once the Girodisc system is in place, simply replace the cast iron rotor when needed.
Sold/priced per pair.
The rotor and hat have a floating mount system, which utilizes 8 or 10 high strength alloy steel drive pins, manufactured by Girodisc in the USA to our own specifications and cadmium plated for a long lasting corrosion resistance. These pins take the load from braking actions while maintaining the axial and radial float between the hat and disc. The pins are secured by grade 12 cap screws with hardened washers. In order to keep the rotors from making noise when cold, the pins are mounted with anti-noise spring washers on the rotor side which allow the rotor to grow with heat expansion but eliminate the rattle and noise associated with floating rotors. This float also allows the rotor to self center between the pads.
Once the Girodisc system is in place, simply replace the cast iron rotor when needed.
Sold/priced per pair.
Details
- A1-322
- A1-322
- Girodisc
- New
Shipping Information
- Item Requires Shipping
- 45.0 lbs.
- W14.0000” x H14.0000” x L8.0000”
- Free FedEx / UPS Ground Shipping!
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