Has anyone used a variable venturi carb ford used.brother had an ex-police cruiser-ltd with one on the 351w.it sounded like secondaries on a four bbl carb opening up.sounded pretty good.

And what most people did. We changed them out for regular 2 bbl. at our shop. The carb is super b-tchy about being kept adjusted correctly all the time and some very complicated adjustment to do requiring dial indicator. The main diaphragm commonly goes bad on them to make absolute h-ll. The top plate leaks air all the time and must be 100% sealed or kiss it off. A very troublesome carb. It doesn't even flow that much wide open.

One should know a couple of very important facts regarding CV type carbs, of which it is one. They NEVER make as much power as a direct opening carb will as the velocity is always high. You get maximum power with denser air, CVs do not allow that. One other thing, they absolutely will not open all the way with a slightly rich setting like you need on hi-perf engines, they open farthest when slightly lean and how you burn up engines.