Dual Quad 318... I used a 273 intake
For "awhile" I had a stock Chev intake off a 265 dual quad Corvette, that a friend had had, and "ported" the barrels to match a pair of carb spacers so they would mount larger AFB's. (They came with WCFBs, the tiny little 4 bbls basially same as the old Rochester "4 jet")
There were some TAPERED holes in all of that!!!