72 340 actual hp?

Any time you make a significant change, like comparing a single plane intake to a dual plane, you need to re-tune the carb to see what works best with that particular intake - jetting, squirters and pump cams. Same can apply even with smaller changes, like comparing carb spacers - with or without as well as 4-hole and open. Otherwise it isn't a valid comparison.

The loss of bottom end with a single plane intake can sometime be compensated for to some degree with carb tuning. It won't necessarily end up better than the dual plane because that all depends on the overall combo - gear, converter, cam, weight, etc. But the difference may not be as wide.