Small ports = velocity at the expense of volume
Large ports = volume at the expense of velocity
You could get very technical about how a cam effects the velocity and airflow, as well as the intake manifold.
I am no head porter myself, you may get some different replys.
Always use the smallest head to get the job done. MOST street or mild 302's dont need larger than a 165cc head. Match your intake/heads and cam. Dont look only at peak #'s on a head, look at the low lift flow. That will alow you to better pick a cam that has timing events that will maximize air flow through out your power range.
Porting usually can make up for a defincency of the stock port flow. If you decide to port a head ist always best to do a before and after to see where your weakness lies. I believe many stock Ford heads benefit from exhaust port work. I am not an expert on port work or Ford head flow by any means.
Strokers 327 and up CAN benefit from a 185 head. Bigger isnt always better, unless you want to really rev high for a street motor. A Vic Jr or AFR205 Would be overkill except on the most radical 302's living large ammounts of time above 7k.
We used a 170cc head on a Chevy 350, still made over 400hp NA.