Originally Posted by usapatriot
CAI: More performance, hydro-lock worries.
Short RAM: Less performance, no hydro-lock worries.
If you live in a wet climate, go with the short-ram. Although rain won't get water in your engine, if you accidentally go through a big puddle you could be in real trouble with a CAI.
With the FSWerks CAI, you don't have to worry about hydro-lock unless you plan on using your Focus as a submarine - you really should not be driving on flooded roads anyway. I have the FSWerks Cool-flo on my 08 and splash through water puddles that send water over the hood and onto the windshield of my car, no problems yet. The only time you need to worry about hydro-lock is if you submerge the filter, then you would be stupid for driving down that road anyway.