How much water is too much,

[LanceS13]

It won't suck up enough to hurt anything.  Small droplets (like rain) will simply vaporize and move on through the engine as inert gas...if they even get sucked that far up the intake.  Water is alot harder to move than air.  It's only bad when you suck in enough water to fill your compressed volume of the combustion chamber.  This much water will not vaporize...and it won't compress like air either, which is where things get nasty.  
Why not just use the grill vents?  That way you can still pass inspection.