This very nice downpipe from Invidia features a CAST bell-mouth collector. It's available WITH a divider to separate the wastegate passage from the main exhaust passage to reduce turbulence at the turbo. Or, save money with a non-divided bell-mouth version.
This is one of the nicest downpipes made, with beautiful machining on the front and back flanges, fully polished 3" stainless steel pipe, and smooth mandrel bends. Comes with a 3" gasket for the back of the downpipe; we would suggest also replacing the downpipe-to-turbo gasket, which you can find here or here.
You have a few choices to make -- see the pop-up options below. Do you want a bell mouth or a divided mouth that keeps flow separated for longer? (The latter costs more, but some people assert that it makes more horsepower.) Do you want to add an extra wideband oxygen sensor bung for your aftermarket wideband gauge? (All of the downpipes come with a bung for the factory oxygen sensor.)
NOTE: Whenever you modify your factory catalytic converter, you may end up with a "catalytic converter efficiency" check engine light (CEL) code. Although you are less likely to have this code if you do have some kind of cat in the system, you may still get the code, even with a high-flow cat.
All these bolt up to most any cat-back that's designed to bolt up to a flat flange. They are NOT ideal for the stock cat-back, but could be made to fit with an adapter.
A rear gasket, nuts and bolts are included. The turbo-to-downpipe gasket is not included.
Fits all US-market 2002-2007 WRX and WRX STi, and Forester XT 2003-2008. Does NOT fit Japan-market twin-scroll turbo cars.
Please read our FAQ page on catalytic converters before purchasing this part.
SKU#: 06477, 05002EX, 05002, 06477EX
Shipping Weight: 63.0 lb