I am going through what i am going to due. Lost a flat tappet cam due to indy rocker failure. Heads are 360-1 springs are 939 comps 140 seat 415 over nose. pulled engine cleaned and put short black back together. I already have a new ft cam. First FT. I never lost what a huge PIA. Years ago had a bracket car duster 3250 446 B1BS heads car ran ran 9.70s in good air usually 9.90 with flat tappet Racer Brown. Switched to a roller cam picked up less than .05. cams were vary similar 272 @50 roller had over.100 more lift. I alwyas ran 150 seat 410 over nose is that to much spring.