The 2 OEM holes under Demon and Dart Sport factory hood scoops are approx. 4" and came with raised grommets to help keep the water out.
As for them not being hooked up to anything.....somewhere I read that it was originally planned, but emissions regulations and/or budgets kept it from going any further. Don't know if this is fact, but seems likely.
Don't know if they were functional, but,
for the sake of discussion: