StealthBox Intake - 15-21 Subaru STI

( 3 Reviews )

Current stock: 0


You've been asking for this bad sally for a while and it's finally here. The intake the for the 15+ STI can be thought of as a hybrid of the tube and filter used in the 08-14 WRX intake and the Stealthbox heat shield used in the 2015+ WRX intake. Small design changes were made, but the overall fit and performance is approximately the same.

Quick Specs

  • Hybrid Cold Air/Short Ram Design - Combining the advantages and eliminating the negatives of both traditional intake designs
  • Air straightener - Dimensionally mimics the factory configuration for accurate MAF sensor readings
  • MAF sensor location - Inside heat shield, isolated from engine bay heat
  • Custom reusable high flow air filter - Integrated velocity stack entrance smooths incoming air
  • StealthBox Heat Shield - Sleek, unique design looks KILLER in your engine bay and keeps the heat of the engine bay from affecting performance
  • Made in the USA - Right here in Minnesota, in fact
  • 30min Installation - Extremely simple with our written and video guides

Why GrimmSpeed?

Sometimes, this explanation is long and technical, especially where performance is concerned. This time, it's simple. The GrimmSpeed engineering and manufacturing teams are known for designing and producing products that use high quality materials, offer perfect fitment and superior craftsmanship and are durable. These intakes are no different and feature the proven performance of the 08-14 WRX EJ motor intake (third party results coming soon) with a look and feel that set it apart from the competition. With the Stealthbox intake heat shield, you no longer need to look like you've got a shoe box hanging out where your factory airbox used to be.

Of course, like all GrimmSpeed products, we stand behind these kits 100% and our goal is to offer you a customer experience that makes you want to stand behind them as well.

GrimmSpeed Intake Kit Includes:

  • 1x Intake Tube w/ TIG welded MAF flange and Air Straightener
  • 1x High-flow Dry Filter
  • 1x Hump Hose Connector
  • 1x Stealthbox Heat Shield Assembly
  • 3x Hose Clamps
  • 2x MAF Flange Screws
  • 3x Precut Rubber Sealing Strip
  • 1x MAF Wire Grommet


  • Red Intake Tube
  • Black Intake Tube


  • 2015-2021 Subaru STI
  • 2018-2021 Subaru STI Type RA

Written - 2015+ STI GrimmSpeed Intake Installation GuidePDF Document Icon

3 Reviews

Dave Bruce 22nd Feb 2023

Fits perfectly, no hassle to intall

Sounds good, fits nicely in the engine bay, added a tune to go with it. Love the sound and cleaner look in the engine bay as well

Shawn 5th Dec 2022

Stealthbox intake for my 2018 STI

I would recommend this to anyone looking to get more performance. When paired with the GrimmSpeed bypass valve it sounds amazing! Quick and easy installation. Easily 5 out of 5 stars.

Add a Review