We were talking about the flow ratings of 2bbl vs 4bbl carbs and why you can't compare the number directly.
A 225 slant at 6000 rpm that is 100% effcient can pump approximately 390 cfm of air. In reality the best you could hope for is 90% effcient or ~ 350 cfm. And any rpm lower than 6000 it's going to be less.
Putting a carb that is way oversize on an engine does nothing for power and will be difficult to tune to run acceptably at anything other than idle and WOT. For a good all around performing engine sizing the carb correctly is very important and it's better to error on the small side than big.