Chrysler Aluminum Manifold 4100337

mbaird said
Part number shows it as a late 70s early 80s piece .
My guess is a Direct Connection part aimed at a specific class of racing . Like my cast iron W2 manifold.

I agree on the date range - specifically 1979. The casting number 4100337 is right in between these other 1979 manifolds:

From another thread on this site:
I have a parts list from 1979. It shows the same 4v intake manifold for both engines - part No. 4100339, casting No. 4100340. It's from a '79 production weights chart and shows the weight at 49.5 lbs. For the 2v, it shows 360 2v as 4100333/4100334 and 318-2v as 4100330/4100331