Japspeed's Decat Downpipe for Subaru systems replaces the standard restrictive downpipe and catalytic converter with a stainless steel, 3″ one-piece item. Increasing the bore of the downpipe and replacing the restrictive catalytic converter allows the exhaust gasses to flow much more freely, increasing the power output of the engine.
Subaru Impreza GC8 Classic WRX STI 1995-2001 models