OldSub is correct about the intake velocity. I once had a set Brodix heads and a Victor Jr. intake on a 350. The engine was doggy until about 3000 rpms, then from 3000 to 7000, you better hold on!!! Go with a mild RV cam, 1.94 intake valves, a Edelbrock Performer or Performer RPM intake and a 600 cfm carb. Also, do not put too large exhaust on it. Also get long tube headers instead of shorties. The long tubes give you better bottom end power.
Phil