GrimmSpeed StealthBox Cold Air Intake Black – 2015-2018 Subaru STI

GrimmSpeed StealthBox Cold Air Intake (Black) , 2015-2018 Subaru WRX STI

The GrimmSpeed StealthBox Cold Air Intake in black for the 2015-2018 Subaru WRX STI is an enclosed cold air intake system that combines the performance of a cold air intake with the heat shielding of an airbox. The StealthBox enclosure seals the filter element from engine bay heat, drawing air from the factory intake duct rather than ambient engine bay temperatures.

DETAILS

• Color: Black
• Enclosed airbox design , shields filter from engine bay heat
• Draws from factory cold air duct
• Larger filter element than OEM
• Direct bolt-on
• Fitment: 2015-2018 Subaru WRX STI

The StealthBox design addresses a key limitation of open element cold air intakes on the EJ257 platform: engine bay heat soak. An open filter in the engine bay eventually reaches engine bay temperature rather than drawing true cold air , the StealthBox enclosure prevents this by sealing the filter and directing flow from the factory cold air inlet. The result is consistently lower intake air temperatures than an open element design.

Installation retains the factory MAF sensor position and cold air inlet duct , the StealthBox integrates with the existing intake architecture rather than replacing it entirely. This means no modifications to factory intake routing and no need to relocate the MAF sensor.

What’s in the Box

• GrimmSpeed StealthBox enclosure (Black)
• Air filter
• Intake pipe
• Hardware
• Installation instructions

Why Choose GrimmSpeed

GrimmSpeed has been engineering performance parts for Subaru platforms from their Portland, Oregon facility since 2003. Everything they make is designed around real-world use , their engineers drive the same cars their customers drive, which means product decisions are made with genuine platform knowledge behind them. GrimmSpeed designs parts in-house, sources quality materials, and validates fitment on the actual application before release. The result is parts that install correctly the first time, perform as advertised, and hold up under the conditions Subaru owners actually subject their cars to. Whether it is a critical engine component or a cosmetic upgrade, the same attention to detail and fit quality applies across the catalog.

The RallySport Take

The StealthBox is the choice for 2015-2018 Subaru WRX STI owners who want better intake performance than stock while keeping the factory intake air path intact. Cleaner installation than an open element intake and more consistent cold air temperature management. Fits the 2015-2018 Subaru WRX STI.

Fitment