340 intake on a 318?
Big Cleveland heads actualy benefit from a raised floor intake port (with epoxy wall flush with gasket) that causes a "port mismatch" on any intake. They sell plates that look to have a flap that bends down into the heads intake port (makes a D shaped port out of an oval port) and covers the low velocity floor. DIY able with thin plate. there is the mismatch again, non issue. look at epoxy modded column
Cleveland Flow Testing