I recently picked up a pair of 57 exhaust manifolds for our 56 Ranch Wagon project off the local Facebook Marketplace and have a few questions; The left side manifold appears to be the high flow EDB-9431 casting, but the right side, even though it looks like the square top high flow has the casting # B9AE. Is this a replacement for the EDB-9430 and will it flow the same as the left side?

Second question has to do with the drilled little plug between the center ports. I assume this is to add heat to the choke tube, but it's not on my 56 manifolds. I'll be using a modified "B" intake manifold without the choke tube so do I need to do anything to this plug or just leave it?

Last question; Looks like there was a casting flaw in the way of a "V" on the #4 exhaust flange. Can I leave it alone and hope the gasket will seal it off or does it need to be filled? If it needs to be filled is there a high heat epoxy I can use or does it have to be welded and ground? Here are some pictures;

  Ron Lane,  Meridian, ID

Are U sure that Choke Heat Port opens into the Manifold or is it just a "Blind" Hole? I don't think it is open as Exhaust Fumes would get into the Carb Choke? Probe it with a Piece of Wire.

  

No, I am not sure. The hole in the top of the exhaust manifold seems to be filled with some kind of material and continues down to the bottom of the manifold where  the plug with the three small holes is. I can't tell what the material is, but it seems to be a spongy material.

  Ron Lane,  Meridian, ID

For what it's worth I had to put a 59 manifold on one side in my 57 and didn't notice any change, just a stock street engine.
Mine was drivers side so no choke opening. Maybe they started filtering the air?

in 59 they started to put the choke hole in the manifold.i think you can leave it unplugged.they flow the same.that little nick shouldnt hurt anything.

Thanks Darrell! Appreciate the Info. So you that the this right side manifold with the B9AE is from 59?

  Ron Lane,  Meridian, ID

yes the 9 stands for 59 but they made them for several years.