Best low profile 383 dual plane aluminum intake?

oldkimmer said
I believe factory 440 hp AVS carbs were about 625-650 cfm. Kim

Depends on the specific engine model as the HP engines got the 750 AVS. Mostly the large people mover cars, wagons and such for the 630 AVS.
(630 as per the old Carter/Federal Mougal phone lines.)