390 w/open chamber heads

We are talking two seperate builds when we mention a 390 (4" stroke) and a 318 (3.31 stroke). It's a HUGE difference between those and the various reactions to parts choices. In terms of a 318 - the general smaller intake = lower end, larger intake = top end fits. That's because the ports in the 318/360 Performer are sized for a 318 and the Performer RPM ports are sized for a 340 or longer stroke 360. Which do you think would better feed a 390?
I think you need to realize that what you're building is changing from a 318 to a 440 and you're considering asking it to breathe through the 318 intake. How fast do you think a 440 would be with a 383 2bbl intake on it? Do you think it would only feel different at higher rpms?

Edit -
In terms of exhaust manifolds - yeah, you cang et that and more but the camshaft is critical as is the rest of the package.