I don't know, I am using the set up from Langdons, and it runs quite well, I do have higher compression, and an RV style cam. I also used water heat. But it runs just fine.
Yes the manifolds I have seen allow for the intake to still be heated. Though it is my son's truck and he has no desire to put any "speed" parts on the truck.
Though I did hear some 216's on YouTube with dual exhaust and they sounded nice though it was not given/clear what other engine mods were done.
