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-   -   My 08 Subbie WRX Prem Hatch (

djorijun 06-02-2011 03:51 PM

My 08 Subbie WRX Prem Hatch
I just purchased one and after a few weeks of trolling this site I'm a bit confused regarding some of the bolt ons I'd like to purchase.
A bit of history, I know how to work on cars, but I've only worked on Honda's and Toyota's and GM's. None with Turbo, and because I've also known turbo cars to be a bit more sensitive I don't want to break anything. That's why I'm here, because a lot of you have helped others and now I'd like some help. :)

Exhaust - Borla Hush or quieter (any recommendations?) I've read a lot about the uppipe, downpipe and catback but still confused. Not sure which is best to own or install.

Intakes - I keep reading that Perrin and others are good, but I've also read that they need to be tuned. Tuned how? when I've installed either CAI or SRI on HOnda's and such, tuning wasn't fully necessary, and here it sounds like a must.

For now this is all I'm worried about, my next thing is suspension but I've got that down. Any help would be appreciated.

bad grocerygetter 06-02-2011 05:51 PM

You have to tune for them because our cars have an maf. (Mass air flow sensor). Wrxs are very dependent on the ecu for real time adjustments to boost, timing, etc... So if you put one on there and don't tune for it the ecu will not know how to adjust due to the turbulence and extra air that come in. Honestly the stock air box and intake is fine for lots of power...well over 300 hp. If you just must put one on i would go with the Cobb short ram and the extra air box you can get with it. This one won't mess with anything like a/f ratios or cause turbulence at the maf. As far as the exhaust if you want quiet you can always just get a downpipe and get an adapter flange and run the factory cat back. Those sound nice and mild. Good luck man.

djorijun 06-02-2011 06:16 PM

So you're saying for the exhaust all I would need is this [url=]Borla Hush Cat-Back Exhaust 2002-07 WRX and STI - Exhaust[/url] both the downpipe adapter and the exhaust are on the page.

turmic 06-02-2011 09:41 PM

That exhaust will not work with your car though. Because it only fits on 02-07 wrxs.

Most intakes need a protune because most of the intakes will not work with a off the shelp (OTS) map. Cobb will allow you to use a Cobb SF intake with their maps and a AEM short ram air intake for the 08+ model years. Perrin can send you a map they made for their intake. XPT OS supports a intake or two for 08+ model years also.

Btw, any 2.5 L wrx/sti engine will not need a uppipe (UP) because they are catless. Unless you want to get a external wastegate set-up, then you need a new UP and a protune for it. Hopefully a few guys familar with quieter 08+ exhaust set-ups can tell you some options for catback exhaust (CBEs).

Good Luck

Bulldog71ss 06-03-2011 01:38 AM

Personally I can recommend Turbo XS for your entire turbo-back exhaust system. It's nice and deep, fairly quiet and does not drone on the highway. It's also stainless and fits very nicely. Oh, and it's pretty much the least expensive on the market.

If you're looking for an up-pipe and or header, I'd recommend Prosport for all the the above reasons.

The cheapest way to do this is to collect all the parts you need, then install them at one time and have your car protuned on a dyno right away. As apposed to tuning after every part you install.

You can get away with a catback without tuning, and I think you could do the intake as well, however most will disagree.

bad grocerygetter 06-03-2011 02:24 AM

[quote=djorijun;262136]So you're saying for the exhaust all I would need is this [url=]Borla Hush Cat-Back Exhaust 2002-07 WRX and STI - Exhaust[/url] both the downpipe adapter and the exhaust are on the page.[/quote]

yeah that one won't fit but no what i was talking about was just doing a downpipe, which is where you will see the power gain and a factory catback with an adapter. Cobb makes a nice catted dp and if you use the adapter to bolt it up to your factory catback it will be nice and quiet...but the cobbs are kinda pricey. Just make sure you look for an 08+ exhaust which ever one you choose. If you wanna help with keeping the sound down i would suggest going catted as opposed to catless.

bad grocerygetter 06-03-2011 02:32 AM

To elaborate on the dp...the factory ones have a metal plate over the wasegate side of the exhaust housing on the turbo...really dumb idea on subarus part but it makes it so when we do change it, its a very big gain with a tune. So technically all one needs to go stage two is a dp and tune. and just like kirt said the off the shelf maps don't offer support for cai or headers. So if you still wanna do a Cobb ap i would drop those items from your list. those items and get it protuned on a dyno and don't bother with the ap.

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