How much extension is needed from ride height with a 700hp, super stock spring A-body combo?

caltracs, monos, and whatever the rancho 9 ways extend to. My junk was running 10.40s with the previous owner, dont know the hp but probably less than 700. I picked up a tenth on the 60' over his superstock springs by putting the above setup on and its not even hooking yet. I only have 6 runs on it, so we'll see what happens, still got a lot more tuning but getting close.