Re: Airflow-constricting flange inside my carb...
That flange is where the intake manifold seats. It is the same inside diameter (I.D) as your intake manifold. Removing it will accomplish nothing but allow the carburetor to slide further onto the intake manifold. Some people use an 'o' ring and some a flat gasket to help seal the carb to the intake and either will seat against that flange. I prefer silicone gasket sealer. Hope this answers your question.
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