I second the two piece motion. If the week calls for rain, switch to short ram. If it's sunny, go cold. Basically, you don't want your engine to suck up water through the intake/intake manifold. Your engine creates a vacuem to suck in air, and if there's water near, on, or in the filter, the chances of that being injested are high. I haven't seen too many cases of hydrolock from CAI's, but just always be aware of what the road conditions are in the rain, and if you see a BIG puddle and it's THAT BAD and you HAVE to go through it, take you foot off the gas and coast, or better yet, kill the engine as you come up on it, coast through, restart on the other side. Works for me....