StealthBox Cold Air Intake

The GrimmSpeed StealthBox Cold Air Intake is engineered to enhance performance for the 2015-2021 Subaru WRX. Inspired by the F-117 Nighthawk, its stealthy heat shield design complements the engine bay aesthetics while maximizing airflow. The intake utilizes a low-bend-angle aluminum tube, minimizing restriction and maximizing performance with a total bend angle of 74 degrees. Its design prioritizes accurate MAF sensor readings, shielded from engine heat, and places the filter within the fender for protection from the elements without excessive heat exposure. This USA-made intake is constructed from 6061 aluminum tubing with 1/8” wall thickness and 6061 alloy MAF flanges. The heat shield features a durable wrinkle black powdercoat finish, and mounting brackets are laser-cut from 3/16” thick aluminum plate. The included components consist of a CNC-bent intake tube with MAF flange, a high-flow dry air filter, an aluminum heat shield, a 12” MAF harness extension, a silicon hump coupler, clamps, gasket material, and MAF sensor screws. Performance testing indicates gains of +32wtq (14.3%) and +21whp (9.6%) across the powerband. However, as with any intake for the 2015-21 WRX, tuning is required after installation. This system is not compatible with the factory tune or any off-the-shelf maps; professional tuning is necessary to maximize gains and ensure safety.