Both the catless and Invidia downpipes have three O2 bungs built in: Two for the factory sensors and one for an aftermarket wideband O2 sensor or EGT sensor. Both the catted and the catless versions will improve exhaust flow and increase the power output of the FA20DIT WRX.

Invidia's downpipe is a great way to start adding Horse Power and Torque. This system was tested in Turbo Magazine, they found that when combined with the cat-back section, HP gains were seen up to 60+ at the wheels with engine management.

The downpipe is constructed of 304 stainless steel with a large bell mouth, which will ensure longevity while enhancing power by freeing exhaust flow. 3" mandrel bent and bolts up to any stock replacement catback or stock unit. This downpipe also has an extra oxygen sensor bung welded in so you can install a wideband oxygen sensor and keep the stock one intact. It comes with a plug installed so you don't have to worry about not having one.