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13 Years of RS
2005 Toyota Corolla :(
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5,532 Posts
Discussion Starter #1 (Edited)
Well, I've decided to go through with building my own turbo kit (with help from people who know what the hell do do!). Here's my thread, incase anyone else has anything useful to say:
http://www.rs25.com/Forums/showthread.php?s=&threadid=3364
and:
http://forums.i-club.com/forums/showthread.php?s=&threadid=204943
Anyways, I'm going to be getting subachads up and down pipes for the turbo, but what about the rest of the exhaust? Obviously, the pipe with the cats between the header and the midpipe won't work any more, since the uppipe will be connected to the header. So what do I do after the downpipe? Can the cat pipe be cut down at a muffler shop and have the flanges moved to work, or would the stock WRX cat pipe work, or do I just need to get something custom made? Or could the WRX cat and midpipe go back to my Stomung without mods? Or am I now in the market for a whole new exhaust? And if so, will I be able to drive it from home to the muffler shop with the only exhaust on the car being the downpipe? Doesn't sound like a good idea, but how else would I get the exhaust made? And I'd like to at least keep the Stomung that I have on the car now, and this is a budget project, so I'm looking for the best option at the lowest price. I was just thinking about this, and I don't know what to do, so I'm turning to you guys (again:D ) for help. Thanks in advance!
 

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No Subie to see here, carry on
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119 Posts
You can use your current exhaust. Most of it anyway. Drive it down with just the down pipe and have them install a good high flow cat, such as a random technologies between the down pipe and the stromung.

You'll want a new 2.5" CAT, not your stock 1.75" peice. You could get one from Summit for about $60 or the Random Technologies would be about $150.

Chad
93 1.8T
 

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13 Years of RS
2005 Toyota Corolla :(
Joined
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5,532 Posts
Discussion Starter #3
Ah, there's the man himself! Did you run any better times Friday after I left? Anyways, I was thinking about doing that, especially now that you point out the stock cat is a 1.75" piece. Driving it with just the downpipe won't cause any serious harm, will it? I'm sure it will through a CEL, but that's easy enough to get rid of. High-flow cat, here I come!
 

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3,614 Posts
there are several companies that make exhausts for turbo'd imprezas, including the RS (Brullen for example). you can buy one of these or have something custom made, or do as subachad recommends above. regardless of method, you probably want a 3" pipe all the way back, due to the added flow from the turbo.

driving on the street with just a down pipe should be fine, as long as you don't get caught ;)
 

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646 Posts
Interesting part is many of the DSM owners found very little difference in times comparing a 2 1/2in exhaust versus a 3in exhaust. Its almost the same as when Options Mag in Japan tested the stock cats against a hollowed out shell of the stock GTR cat. A incredible 1 to 2hp increase. Now granted your thinking of dropping the narrow stock RS stuff for something larger all together but I just wanted to point out that 2 1/2in or 3in aren't going to be vastly different in peformance. The stock exhaust manifold and those bends in it not to mention the narrow size would be another good start but other then having a shop make the WRX exhaust manifold work I don't see any other way around it.
 

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13 Years of RS
2005 Toyota Corolla :(
Joined
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5,532 Posts
Discussion Starter #6
That's why I'm planning on keeping as much of the current exhaust as I can. Since the cat pipe I have won't work, I'll free that up with a high flow. Not sure if I'm going to get the midpipe done at the same time, as I don't remember off the top of my head what size the stock one is. 2"? But I'm keeping the Stomung, it's big enough, it looks good, and I love the sound. Plus, I'm only going to be running 5-6 psi, so I think a 3" would probably be overkill.
 

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13 Years of RS
2005 Toyota Corolla :(
Joined
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5,532 Posts
Discussion Starter #8
subachad said:
HondaH8ter, check your pm's, your up pipe is ready. :)

For anyone else that might be interested, I could have another 2 ready by next week.

Chad
93 1.8T
YIPPEE!!!!:D
 
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