Electric exhaust cutouts?

[B.man]

Cool thanks, I'll let you know how it goes.

[B.man]

Since I don't plan on going any hire than the 2.5 xtr, should. I still go with the 44mm?

[MainFrame]

The 38mm would be large enough. 38mm will be louder/higher pitched compared to a 44mm dump tube.

[Heide264]

If you exhaust has a cat in the down pipe, you may (probably will) have clearance issues with the dump pipe. That area is pretty tight clearance wise, even with a catless down pipe (at least it is on mine).

I agree to go with an EWG over a cutout though. The reliability will be much higher. Also, if you put the cutout before a catalyst, it will be near impossible to tune your boost control across both configurations (the catalyst will have an effect on your boost control tables). You may have boost creep issues as well if it is before the catalyst.

I have the 44mm grimspeed kit on my 2011 STi, fwiw. I had to grind down the vband flange a slight bit on the dump pipe. You may be able to request from grimspeed that they do that for you.

If you go EWG, you'll need a tune. I'd advise against any off the shelf tune (nor do I know of any that would work). I'd recommend just getting a professional tune. Consult with your tuner before the install, so you configure your EWG (both spring pressure and vacuum/boost connections) as the tuner expects you to.

[EJ257]

If you exhaust has a cat in the down pipe, you may (probably will) have clearance issues with the dump pipe. That area is pretty tight clearance wise, even with a catless down pipe (at least it is on mine).

Depending on the location of said cat...

The Invidia/CNT (or other brand) downpipe that has the cat in the upper half of the downpipe would have more issues than one like TurboXS/Cobb (or other brand) that puts the cat further down the stream