K&N Silver Typhoon Short Ram Intake System Subaru WRX / STI 2002-2007 is designed for optimal performance. The Typhoon uses a velocity stack design to force air through a massive 5in inner diameter K&N high-flow filter and into a cast aluminium intake body and MAF-housing. The K&N WRX & STi typhoon intake includes a heatshield that builds an underhood cold air box, that lowers intake temperatures and forces air through the intake for performance you can feel. How much performance? K&N has seen gains of 12whp on an STi, 14whp on a 2.0L WRX! K&N's comprehensive Typhoon Intake kit includes all the necessary installation hardware, include heatshielding for the MAF sensor, and comprehensive instructions. The filter is reusable, and can be cleaned and recharged with a K&N cleaning kit.