kustomizm wrote:New rotors too? These are not glass smooth. I can turn them or get new ones too.
I'm not sure we should have an opinion on that without seeing them and knowing what pad type they have now vs what pad type you plan to put on.
Rotors that have been used with one pad and not cleaned (turned down) can sometimes interfere with the bed-in of the new pad, especially if it is a different chemistry type.
If you don't turn or replace them and they aren't planar and smooth, pedal feel will generally suck for a good long while after changing pads, which will make back to back comparison impractical, and is way less fun with an upgrade.
For some perspective on turning rotors, 1.8 miatas have bigger brakes than 1.6 miatas, so naturally in classes where update backdate is allowed, people often run the 1.6 brakes on the 1.8 cars. Because they are lighter. And we don't really need thermal mass at autocross.
Some people turn their rotors to save weight legally in stock class. Personally, I don't think that is anywhere near worth the downsides of shorter (or much shorter in my experience) rotor life after turning and further reduced thermal mass, so my attitude for my own cars is that turning rotors is a waste of money. I've settled on a pads type and I'll live with a funky pedal feel for a few hundred miles at pad change time, though. I'm on my 4th pad change on the stock rotors, and I'll do new rotors with the next pad change, because they are starting to be significantly not flat, and while over the minimum thickness spec, they are starting to go bell shaped.