I am looking for a set for a mild street strip 440 with edelbrock rmp's with the 590 purpleshaft cam. I ran a set of cheap pro forms for years and they seem to work good for me on that. These ones have the bearing in them and they have the nice 12 pt. nut with adjuster. These look nice compared to my old mopar permormance aluminum ones Im running with my roller cam 500.