ETS 03-06 Mitsubishi Evo 8/9 Standard Tank Intercooler

This intercooler replaces the Evo's factory front mount with a larger 24-by-11½-inch core to remove more heat from compressed intake air. I'd use it when higher boost or repeated pulls overwhelm the factory cooling capacity. Choose thickness around the airflow and heat load rather than simply buying the largest core.

ETS lists the 3-inch and 3½-inch versions as retaining the crash beam; 4-inch needs beam trimming, 5-inch also needs custom piping, and 6-inch requires beam removal and bumper cutting. Those larger sizes involve a substantial fitment tradeoff.