Ok, I have a question, which may seem stupid. If you have a big brake kit, the entire rotor assembly is often several mm thicker/taller overall, meaning the height is greater. For instance, from what I understand, the height of the BBK rotor for the Wilwood kit is ~54mm (28mm thick rotor, with a hat offset of ~30mm and a thickness of ~6mm).

From what I understand, the height of the stock rotor is about 40mm (25mm thick and ~15mm for the "hat" part). If the height on the Wilwood rotor is around 14mm greater, how does one properly torque their wheels? Isn't this in essence the same as having a ~15mm wheel spacer on a stock rotor? If anyone could clear that up, that would be great.

 

Remember, the only thing affecting the actual mounting of the wheels to the hub would be the thickness of the hat portion of the rotor. It doesn't matter their offset, as that only determines their placement relative to the hub. Likewise, the thickness of the actual rotor doesn't matter either - it won't change the distance the wheel is mounted from the hub - the only thing that affects it will be the hat portion.

Overall, when you sit the rotors on a table, the bbk rotor should be 15mm taller, yes. But when you mount everything up, the only part that matters with respect to the wheel being mounted closer or further from the hub is the hat.

Hope this helps a little bit.

 

When I installed my Stoptech's, I compared the hat mounting face thickness to oem. The difference is negligible, around 1mm or less. The rotor offset is different, however, but does not affect the mounting offset.