Add some quick horsepower to your WRX or STI with the new Mishimoto Subaru WRX/STI Performance Air Intake. This kit is engineered specifically for your Subaru WRX or STI and includes everything needed to replace the restrictive stock airbox. Mishimoto engineers spent months fine-tuning this design in an attempt to squeak out every last bit of performance. This dyno-proven air intake provides 25 hp/25 tq gains over the stock intake while maintaining safe air/fuel ratios, perfect for some extra punch on the street or autocross course.