The FIPK makes more power because of the plastic tube. Get the FIPK over the typhoon kit. K&N came out with the typhoon kits because there was a demand for colored metal intake tubes. Even though they make less power.
Plastic tubing does not absorb heat as much or as fast as metal tubing, keeping the intake air cooler. Cooler = more power. Matt's correct - go plastic.
Also look: http://www.demolet.com/
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