we did a track day with the Mclaren club, and they had a few P1's out there. the P1 has a Diamond Like Coating (DLC) on the ceramic disc brake rotor. its really obvious, as the rotor is flat and shiny like a mirror, no grooves, no scratches.

Too expensive for real production engines at this point, like the cera-metallic coatings Mazda used in the Lemans engines.

Also, note of DLC used on ceramic brake rotors-

Wiki says-
Despite the favorable tribological properties of DLC it must be used with caution on ferrous metals. If it is used at higher temperatures, the substrate or counter face may carburize, which could lead to loss of function due to a change in hardness. This phenomenon prevents the use of DLC coated machine tool on steel.

So, maybe wouldn't work with steel apex seals or SIP insert.

 

lol, yeah the P1, is quite pricey!