Not sure if any SFT cam change would show a big improvement without taking the time to try a bunch of different ones.
Not to mention that most of the fast rate stuff is probably going to require higher spring loads than what std lifters are going to be happy with if you’re trying to buzz the motor 8000.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
