2bbl to 4bbl conversion?

Well; the carb will flow whatever the atmosphere is able to jam thru it.
A slanty at 1000rpm and WOT might pull 65cfm. by 3000 it might be up to 196cfm @100% VE. By 4500 shes wanting 293cfm at 100%VE. But in stock form;more likely is 60% VE so 176cfm.
A 318 of course will be 318/225=1.41 better or 249cfm@4500@60%VE.
In reverse math; 285cfm is good for a 318 at up to 5150 at 60%VE That doesn't mean anything special will happen at 5200.lol It's just done making power...... which is Ok cuz the stock cam power-peaked a long time ago anyway,lol.
Ok so but say you put a 600 on the stock 318, and increased the VE to 65%. And with a cam that peaks at 4500, you might shift at 4800, so the 318 might pull 286 cfm@4800........ thru that 600, so the only change is that the air is moving more slowly thru the 4bbls 4 throttle valves than when it was hustling thru the 2bbl.
But will it by faster? IDK, math ain't everything.
If nothing else, it sure sounds faster.