AVS (Air Valve Secondary)

Has the adjustable secondary air valve and the potential for more cfm than a single AFB. The comparitively small cfm of the AFB's (most were rated at 625cfm or less) is why many were used in dual four barrel applications to provide enough fuel for larger cid engines, and as singles for smaller cube or typical lower HP passenger car V8's. The AVS was a nice middle of the road carb, very tunable and could provide more cfm (up to 850 or so) with a single four barrel carb.