I bought this last weekend just for the mystery of it, and I've been following @tlowe 's mystery intake thread, so here's another one. I think this one is much earlier, it's cast iron, and the black on it I think is porcelain/baked enamel, it looks like what's on my '41 Cadillac exhaust manifolds, but it's not from a Cad flathead V8, unless it's a super early one. The ends on the underside look like they had some milling/machining done to them, possibly after it was made, it might even be a cut down version of a larger manifold, I didn't get any history on it. There was some welding repairs started on one end, the machining might just be cleaning that up too, no idea. The guy I got it from had a '41 Cadillac, a 42-48 Lincoln, a mid 20's Buick and a couple different Packards although I can't find anything that looks anything like this on any of those cars.
Looks to me like a carb warmer, with coolant through, possibly between two heads on a narrow V-8 or twelve. Packard's had some wild inductions. They love that black baked enamel, as well. Someone will know. Bob