For engines close to stock tune (any size, but mild cam) full vacuum to the distributor works well.
As the cam approaches 240 degrees @ .050", full vacuum works at idle, but as you open the throttle vacuum quickly dies, which reduces RPM, etc.
Ported fixes this, since idle is based solely on initial advance it's completely stable until a later throttle position.
You can even fab a new port position by inserting a small tube right through the casting to a point (generally slightly higher to delay vacuum) than the original, which will not add vacuum until slightly higher throttle disc angle. Hint: doesn't need to be horizontal.
Try both, keep the one that works best, cap the other (don't blank it), it may help the next time you change your tune-up.