[BRENT in 10-uh-C]

I have done this. Did it several years ago trying to mimic a 'B' venturi & B throttle blade on an A carb. I was using a Superflo bench set-up for motorcycle & kart cart carb(s). I would probably try to do it again now that I have CAD and access to CNC machining, but if you just try to do it freehand, you have a much greater chance of making flow worse than better.