I've upgraded my carb (from 12mm Weber) to the Dellorto 17.5mm and swapped in a Malossi big-bore. Also running a Malossi red filter and a Wild Lion exhaust. I've read that I should leave the airbox alone and I've also read that I need to drill some additional air holes in the box.

In my mind it seems like I should be sucking a lot more air than the stock airbox was originally designed for. Is the stock box sufficient or does my ET2 need more air?

Might be worth noting that I live at 5000' elevation so we're already a bit short of oxygen.