not sure about is300, but some intakes you can change from cold air intake to short ram. so you get best of both worlds. if not, look up instruction manuals for cold air intake brands and look at where the design/location of the pipe and intake. you dont wanna be like this guy
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my cold air intake sits right behind the front bumper so no water soaks the intake (i tested with a power washer too).
but i would say...go for the short ram intake. it will sound better, still gets a gain of hp, and easy to clean! i need to clean my filter soon, so i have to take off the bumper which i dont want to do at all. i got a cold air intake because many people who have my car goes with cai
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