By nasty marks I am assuming you mean you have hot spots on your rotors. Unless your getting vibrations I wouldn't bother changing them. I got them before and they went away after some normal driving. Now I used Frozenrotors and they seem to be holding up much better and they are not much more then OEM blanks. There's also a 10% off code I found
here. Those brakes are going to be loud, it's normal. I am getting the stillen front bumper and cooling ducts installed "soon". You can try RBF660 but be mindful it has a much higher tendency to suck up water from the air. Also you might want to get a basic brake fluid tester or just change the fluid prior to every event. Can't think of anything else you could try.
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GTR TT 493Whp/431lbft, Ecutek, Southbend 6puck,Quaife, RPM RollBar 4Point, R888R, JRZ RSPro F(10R/10C) R(10R/6C) 1000f500r inlbs+150inlbs Tender, SPL everywhere.
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