You'll see minimal gains with just a filter on a standard tune. (As in 1hp if that)
It all comes into play when you start pushing it, a filter is a restriction so you will want a high flowing filter when you want to push the tune.
If it was me I would use an after market panel filter in the stock air box (what I have now). I'll be changing to a pod filter only because I am going to angle mount and can't utilize the stock box (I think... still checking
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