340 Manifolds, Reproduction, Any interest?

69_340_GTS said

You really wouldn't need CNC machines, but no matter how you do it there is a lot of machining on these. Don't forget the deep counterbores on some of the bolt holes, plus on the drivers side the flange vs the exhaust outlet are on a compound angle which need to be done exactly as the factory did it in order for stock/repop headpipes to hook up properly. Plus, how about the machining for the exhaust heat valve? People looking for "stock" parts will want that in there too. The $1000/pair price someone else mentioned does not seem far off!

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6 of one 1/2 a dozen of the other....The CNC is more accurate, repeatable and fast but more expensive because a three/four axis CNC machine cost way more than a manual machine and involves programming. Machining these manifolds "manually" incurs no expensive CNC machine nor does it require programming. But machining anything manually is much, much slower (cost/time), less accurate and labor intensive all of which drive the cost up. Moreover, if machined "manually", the compound angle between the engine/exhaust surface and the exhaust outlet/heat riser would require that the manifold be done in "stations". One station/machine for each machined surface. This was probably how it was done originally!! Each station would require a different fixture (more cost) to hold the manifold at the proper angle. When you make many thousands of manifolds the "station" method is very effective and that's probably why Mopar used that method.
So no matter which route you choose it cost too much to make a small batch. Expensive machine/programming OR expensive labor/time.


I do not wish to discourage "magnummopar", I was just shedding some light on the subject of machining!!

Treblig