Exhaust FAQ

[eightyseven]

So I found this catalytic converter. Can anyone tell me if it would fit on my 2002 WRX? I'm trying to get as much as I can for as little as I can.

Magnaflow Catalytic Converter - 94100 - Stainless steel, Universal product, High Flow
Universal - Fits all vehicles -- MAGNAFLOW 94100 SERIES UNIVERSAL FIT CATALYTIC CONVERTER -- 49-state legal; Not for sale or use in California; Cannot be shipped to California addresses; 3-way catalyst style; 2.5 in. inlet; 2.5 in. outlet; Single inlet and outlet configuration; 9 in. body length, 6.5 in. width, 4 in. thick, 13 in. overall length; 6,000 lb. GVW; With one oxygen sensor port; Ceramic honeycomb catalyst substrate; Oval stainless steel casing; The main benefit of this catalytic converter is that one unit may cover a wide variety of vehicle makes and models; Installing this converter often requires the use of welding, cutting, and tube bending equipment that is readily available to most professional installers.

[nxwrx]

ok so I just got my 2011 wrx hatch and was wondering what size the stock exhaust is so I can make sure I get the right down pipe.

[jd92677]

ok so I just got my 2011 wrx hatch and was wondering what size the stock exhaust is so I can make sure I get the right down pipe.

2.5 inch

[Mholmes06]

So I am new to the WRX world, I just bought a 2006 WRX LTD. All my life I have owned big V-8's so the small engine is kind of a new world to me. My biggest question right now is the car came with a full 2 1/2 straight pipe exhaust system with down pipe. I do not believe it has a cat or anything on it, so besides being extremely illegal what is everyones take on this? I am not one who needs anything extremely loud, I prefer just something that is clean sounding. And secondly if I changed the Exhaust system will I need to have it re-tuned. Supposedly this car came with an upgraded ECU. Any advice here would be greatly apprciated, thankyou.

[nxwrx]

is it ok to run w/o the stock axel back.i have a 2011 with a dp stock cat back

[Donkey]

So I am new to the WRX world, I just bought a 2006 WRX LTD. All my life I have owned big V-8's so the small engine is kind of a new world to me. My biggest question right now is the car came with a full 2 1/2 straight pipe exhaust system with down pipe. I do not believe it has a cat or anything on it, so besides being extremely illegal what is everyones take on this? I am not one who needs anything extremely loud, I prefer just something that is clean sounding. And secondly if I changed the Exhaust system will I need to have it re-tuned. Supposedly this car came with an upgraded ECU. Any advice here would be greatly apprciated, thankyou.

Possibly. The only down side is you would be boosting slightly less depending on what you do.

[Donkey]

is it ok to run w/o the stock axel back.i have a 2011 with a dp stock cat back

I have no idea what your asking. Use complete sentences. See mholmes 06's post on how to actually ask a question.

[nxwrx]

so i have a 2011 wrx with a dp and stock cat back.i was wondering if its ok to run with out the axel back exhaust and just open mid pipe?

[jd92677]

so i have a 2011 wrx with a dp and stock cat back.i was wondering if its ok to run with out the axel back exhaust and just open mid pipe?

It's fine but why would you want to do that?? It'll sound like hell

[Donkey]

Not to mention you want the exhaust to exit the vehicle somewhere other than underneath so you don't CO poisoning at a stop.

[rc_wizard24]

Hello all

I'm kinda new to the Club WRX world and was wondering what size exhaust system I should use on my 2008 WRX sedan. My current mods are a K&N Typhoon intake system, perrin light weight crank pulley, and a short throw shifter (not that the latter 2 would have anything to do with an exhaust lol). I've heard some people say that I should get a 3" system because back pressure is evil to a turbocharged engine. And other are saying that a little back pressure is good and I should get a 2.5" system. What should I do?

[metaldahlberg]

Go 3". Invidia makes good stuff at a good price. Definitely get a tune also for the intake and exhaust.

[rc_wizard24]

Go 3". Invidia makes good stuff at a good price. Definitely get a tune also for the intake and exhaust.

I think I'm gonna go with the 2.5". I've posted the same question in another section of this website and others are telling me that my TD04 turbo is prone to turbo surging with a very less restrictive exhaust system.

Do you know if a good quality BOV would prevent a turbo surge?

[SwampAssassin]

I was thinking about going with the invidia but ended up going with the HKS.. A little more but i have never regretted it for a second. and the BOV i also went with the HKS ssq, havent had any problems with either..

[2002_wagon]

I had a hks dp and then changed it to a titek bellmouth dp it gave my a little less restriction