I know this has been discussed before, but they deliberately crippled the Mopar motor's power output with a 170 cc-runner intake manifold!
Freiberger says they used the Edelbrock 190 cc-runner manifold on the Ford because it cost the same as the 170-cc-runner manifold and "nobody in his right mind" would buy the 170 cc manifold with ports too small for the head, for the same price as the 190 cc manifold.
Maybe replay the video again. I believe you confused intake manifold with heads. Both engines used Edelbrock heads, they don't make the Mopar head with a 190cc intake volume, only 171cc. Now, you are right with respect they could have used the 170cc Ford head for a true size comparison. Instead, they went 190cc because of $$$ value. Has nothing to do with porting an intake. At the beginning, Dulcich even says that the 170cc head is undersized for a 408 inch engine. Listen to the last 3 minutes. There just aren't many options for LA motor cylinder heads.