A1-066 Girodisc 2pc Front Brake Rotors (OEM Steel) 1 "a"


A1-066 Girodisc 2pc Front Brake Rotors (OEM Steel)


This Girodisc system is a 380mm two-piece steel rotor and aluminum hat combination, a direct-replacement upgrade for the one-piece OEM GT4 steel brakes. The A1-166 will bolt directly to the GT4 and work perfectly with your OEM calipers. There are two main reasons for replacing your OEM rotors: first, the Girodisc rotors are designed to shed heat more effectively than the original rotors; second, the slotted Girodisc A1166 will far outlast the OEM drilled rotors. When subjected to intense heat in a racing or track-day environment, the drilled holes in the OEM rotors originate cracks which can lead to rotor failure. When paired with the Girodisc A2-155 rear rotors, your factory brake bias and ABS efficiency are maintained.

When used with Pagid or PFC performance brake pads, and Discovery Parts RF1 brake fluid (also available from CompetitionMotorsport.com), you have an amazing solution to overheating, cracking and warping rotors.

The central hat section of the disc is made from 6061-T6 aircraft specification aluminum. The disc is manufactured from cast iron which is constructed in the USA and is made to the same specification with the same material used by professional racing organizations. The rotors curved vane design was developed in racing and acts as a centrifugal pump to force cooling air through the disc.

The rotor and hat mount together through a floating mount system which utilizes eight to ten high strength alloy steel drive pins manufactured by Girodisc in the USA to our own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by Grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.

The two-piece Girodisc design allows for rotor only replacement as well to minimize future replacement costs and deliver outstanding performance and cooling.

Sold/priced per pair.

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