If you're trying to get more air into the system, begin with a Tickford snorkle (if you haven't already got 1) then try the extra intake at the front of the airbox to pick up air flow from beneath the headlight. Unless this hole you refer to is for some other purpose?? Conduct a search on these here forums, there's a few articles regarding air intake mods. Note: if you're running duel fuel, too much air is not always a good thing.
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