Best Intake for a 408

Still is. (for a street/strip car).
Edit: i would try the rpm and the victor, see which one i liked, and sell the other.
^^^ This. Until you try both with the rest of your combination, you won't know for sure. If you don't want to spend the money to test 2 intakes, I'd lean towards a Victor 340. As others have mentioned, you have enough cubes to overcome any low end torque issues that a single plane might cause.