Ford used a VV (variable venturi) carb over a span of years in a series of efforts to control emissions and avoid fuel injection. They work, and sometimes work well, but are more complex than a simple 4 bbl carb. Some require connections to and ECM (computer) to operate; some don't. If yours requires those connections, it would be simpler to go with a Motorcraft 4 bbl.

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1982 300SD " Wotan" ..On the road as of Jan 8, 2007 with Historic Tags