Used in common on a plenum manifold, the carburetors should be relatively small; the OEM for similar but smaller engine is recommended (2 216 carburetors on a 235, 2 X 235 carburetors on a 261, etc.).
However, if each carburetor only feeds a pair of adjacent cylinders (#1 & 2, 3 & 4, 5 & 6) they should be larger than the original carburetor,as much as 3 times the CFM called for in the common CFM calculation (D × VE × RPM ÷ 3,456).
The original Corvette used 3 X Carter YH carburetors, certainly not "very small" with 1½" throttle discs and 1-5∕16" venturi.
