New Guy - '65 273 Valiant Convertible

Two7T3Dart - since there's no commentary in the parts section (from what I read) I'd like to ask you here: is it the 4bbl carb that makes the difference between a regular Valiant (Signet in this case) and a Commando?

This car had a 2bbl originally and during this rebuild I had the 4bbl manifold/carb put on with pretty much stock cam I think (?). I just wanted the power when I needed it and the economy when I didn't need power.

So much to learn - thanks for any info.