1 piece rotors vs 2 piece rotors

[Apogee]

...and there are two main types of performance 2-piece rotors, floating and fixed mount designs. Most OE replacement 2-piece rotors have the same hat thickness as the OE disc it replaces. Average weight savings in my experience is 2 to 3.5 pounds per rotor, which is always a good thing, although at hundreds of dollars per pound, certainly not for every budget.

Fixed mount 2-piece rotors are just that, fixed, where the hat is directly mounted to the disc with high-temp (hopefully), high-quality stainless AN hardware. DBA5000-series rotors use this configuration (as do many Wilwood and other rotors) and are popular in a lot of rally and other relatively dirty applications, and while lighter than equivalent 1-piece rotors, these can still exhibit some issues with "coning" due to the differences in the thermal expansion of the disc and hat.

Floating discs can use a variety of mounting methods that allow the disc to thermally expand with minimal resistance from the hat to doing so. Bobbins, t-slots, radial grooves, etc...they all have their pros and cons, but they all function on basically the same in principals, some just better than others.

Tobin
KORE3