318 heads no matter what casting 'as cast' do not flow better than a small valve 360 head.
Mill a 360 down to 64cc and drop it on, you'll make more power with it as cast
If you could port the '302' 318 head to flow the same or better as a 360 head...then u'd have something better by virtue of a closed chamber and the fact that your moving the same air through a smaller hole=broadens torque, especially low end...but then again you'd want to maximize the compression ratio/dynamic cranking psi 'use the right piston as well' to realize the full potential/quench
but then later on... u'll realize the 360 has more in the flow department, but that will only com into play if you need over 240-250cfm, thats when the bigger port takes over.
fwiw