i want to purchase a turboback exhaust system for my 02 wrx wagon but right now funds are tight. i was wondering if its possible to buy a borla hush catback then add on the down pipe etc. to make it into a turboback.
will the borla be to restrictive?

thanks for all input

 

You can add a downpipe at a later time. Most, but not all, downpipes are made with neckdown flanges to bolt up to OEM flanges. The 3" Borla Hush flows better than the stock catback, but not quite as well as some other (louder) catbacks.

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0==WW==0
"…axles of evil…" - george w. bush

 

Here's what I did:

The plan...go to a reliable and inexpensive stage 2. BTW...already had replaced the intercooler hoses and did the intake hack.

Purchased Cobb Accessport. Flashed ecu to stage 1 to get used to it. Purchased and installed (~ 1 month after flashing to stg1) '04 STI uppipe, Helix v2 catted downpipe, '05 STI catback and flashed ecu to stage 2.

Results: exactly what I wanted! Cost was around $1200, everything is stainless so should last a long time, very stealthy (sounds great, btw!) and nice amount of extra power. MPG hasn't gone down and, if anything else, has gotten a bit better.

Some people have had issues mating the downpipe (flat flange) to the stocker/STI (donut flange)...ie., exhaust leaks. Mine, though, has been running for ~2 months with no issues.

As for being restrictive, I belive that going from the stock (2.25") to STI (2.5") is enough for stg2. If you plan on a turbo upgrade go with the 3" exhaust. The majority of your additional power, from what I've read, comes from the uppipe & downpipe.

I'm by no means an expert here, but I went through a ton of research before making my decision and the results ended up perfect, for me. If you want any pics or some sound clips of my setup let me know.

 

I have a 3" Borla "Hush" catback on my 04 WRX and I love it!
The sound is not to loud and is perfect in my opnion.
From what I see with adding just a catback you will only see
5-10 whp but, your exhaust will flow alot better though
witch is good.