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GrimmSpeed 2015-2021 Subaru WRX FA20 Stealthbox Air Intake

GrimmSpeed 2015-2021 Subaru WRX FA20 Stealthbox Air Intake

Regular price $399.00 USD
Regular price Sale price $399.00 USD
Sale Sold out

Inspiration for the StealthBox Intake came from internal discussions about what we wanted from an intake system for the 2015+ WRX. Of course, performance is the highest priority, but at GrimmSpeed so much more than that goes into a product. We wanted an intake that purred quietly under normal driving circumstances but would roar at wide-open throttle. We wanted an intake that looked at home in the well-sported 2015+ WRX engine bay instead of a shoebox stuffed into the fender area.


  • Low-profile heat shield protect air filter and MAF sensor
  • Utilizes factory scoop for fresh air supply.
  • Custom performance air filter with built-in velocity stack.
  • High-flow CNC bent and laser-cut aluminum tube.


  • +32wtq (14.3%) and +21whp (9.6%)
  • Designed in CAD - Perfect mating with the factory turbo and ram-air scoop
  • Low bend angle aluminum tube - Minimize restriction and maximize performance
  • Shielded MAF sensor placement - Protects MAF from heat, which increases the accuracy of readings
  • Made in the USA - Manufactured right here in Minnesota

Please Note:

  • Take care to install the air filter onto the intake tube properly. Push the filter onto the tube no more than 1" before tightening the clamp. This will ensure that the velocity stack within the filter is allowed to function properly!


  • 2015 - 2021 Subaru WRX

Off-Road Use Policy

By purchasing this product, you are acknowledging the use of this service is explicity for Competition/Off - Road Racing ONLY. It is the responsbility of the buyer to remain compliant with local, state & federal laws regarding EPA restrictions.

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