Hey tod74,,I`m sort of doing the same thing with a 588,,I`m really looking at the AFR 357 CNC, and want to keep mine under the 7000 range also, I have been using a set of shaved 305s from afr and they work good, but like yourself, I would like to try something bigger,you are running more comp. and cam than me, so either the 357 or the 335 should work,,the 335 would give you a little more torque. they both flow about the same to 700 lift.