The groove was only a wear indicator. I just chunked my tired rotors in the trash. The new ones I put on were not grooved.
__________________
73 Camaro LT/Z28
383 W/ 450 HP 455 TQ
3" exhaust with Hedman Hedders and flowmaster 40's
Mk VIII electric cooling fan
Vintage Air A/C
3:08 Posi