Carb to intake transition theory question.



I have a friend with a machine shop. Lately he's been making some cool 2-4bbl adapters for another racing outfit that start with the two standard holes and then radius out. Looks like It'd flow really well. This got me to thinking, why have carbs always had perfectly flat bases? I realize it'd be the cheapest and easiest for O.E.M., and on an intake that does not have an open plenum design it's just whats needed. But on an open plenum intake I think it'd make more sense to have some sort of transition area. Either in the intake, in the carb base, or in some sort of mid-plate. Huge amounts of R&D have gone into both intake and carb design so surely someone has looked at this before. Just looks to me like moving air through the small area of the carbs and then just dumping it instantly into an open chamber would not be the most efficient design.

What do you think?