Brad, I am currently working out the final rocker arm stage w/Hughes 1.5 cryo treated kit for Victors.They have banana grooved, .190" shafts. I recently purchased these,new, and worked w/ Mike at B3 for geometry correction.Nice and intelligent guy to work with. Very helpful. He had good things to say about the quality of the Hughes shafts, and his work appears spot-on. Hughes website has alot of good information about this, including testimonials from users,one claiming using valvesprings 330#/725# ratings at 7500rpm. $135 pair.
I am using them myself w/285#/670# springs w/.690" roller,also looking at 7500max .Hope this helps. Bill
