Please tell me if this is correct.
Oops, bad proof-reading on my part; It should ask; is that a 4-bbl on an engine with a cast iron oem exhaust manifold?
Bad?,no. Effective?,no.
But it could be a split manifold, I just can't see it in the pic. Some creative fellows have cut the oem manifold in half and welded on a second dump, then installed dual exhaust. Not as good as a header, but somewhat effective at lower rpms.