Pictured below is an original era aftermarket Bendix Stromberg downdraft cast iron intake manifold for Model A & B Fords.
This particular intake is not marked. I have another near identical one which also has the Bendix and Stromberg name cast-in on top of the runners.
The vertical riser tube is 1-7/16 inch ID compared to original Model A size of 1-3/16 and original Model B size of 1-5/16 inch ID.
It also uses a larger 2-11/16 inch bolt pattern to fit the Stromberg DXR8 carburetor.
The carburetor mounting studs are 3/8 inch diameter compared to the 5/16 inch diameter bolts used on original Model A and B carburetors.
This manifold also has an original style 1/8-27 NPT thread vacuum port for the windshield wiper vacuum line fitting.
This pic above shows the hard turns and also the through-boss for the throttle linkage bellcrank. Also has original Model A style hotspot-to-exhaust manifold mounting.
Pictured above is perhaps the most interesting feature. Both runners have a factory drilled 3/64 inch bleed hole at the bottom of the casting. Presumably used to drain flooded gas. I wonder whether these holes stayed open or plugged up, and how it affected idle mixture over time?
From Ford Dealer & Service Field.