JohnD is 100% right - you want your intake system to have the least possible restriction in it. Venturi is only relevant with carbs as it's purpose is to deliver atomised fuel into the intake tract. With fuel injection no venturi effect is required as the injector nozzle does that for you.
If you tap into various points of your intake - before filter, after filter, without filter, manifold at WOT etc you can measure the pressure drop. The air intake tract needs to taper down towards the intake valve as this accelerates the flow. The intake valve should be the most restrictive part of the intake system (we're talking at WOT here).
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