Head porting

Quite a coincidence here. I'm just now building a 408 using the same heads and cam. I got started working on the heads last week then the block came back and I need to get it assembled so it doesn't rust so I side tracked the head work. Will get back on it late next week. I don't have much to add for the process as I've never done any of these either. Just X and J heads. But the basics are the same for all heads. As mentioned the port speed generally runs high in these heads I'm told by a few reputable head porters. But with the intake on it slows. The high port speed is most likely why the flow drops off at high lifts. It's probably going turbulent. But again maybe the intake will slow it enough to remedy that. Let us know how they flow with the intake on. BTW: I'm wondering if the M1 single plane intake might be a better choice since it's not quite as high velocity as a dual plane?? Just thinking. I have a Torker2 and a Air-gap and I plan on testing both on mine to see how the numbers look.