What worked best for me back in 1991, my '69 Cuda 3300lbs with home built 446ci motor, 6pk bottom end, Team G, 850DP, 9.8:1, 4800 stall, stock 906's, ran a best of 11.2@118+. Did nothing else but bolt on some 2.14/1.81 906's mildly ported to around 260cfm with HS r/rockers and went 10.7@125 first pass NA. Was running the old MCandless .650"/290@.050 sft cam, and they say it needed 12.5:1 to work, how much faster would it have gone@12.5:1, not that much more I doubt, perhaps a 1/10th?...and there was quite a lot wrong with the car, too loose front end, would top out and not enough air in the 32's to name but 2, would've been a 10.5 car with those sorted.