Exhaust choices

Discussion in 'Modifications And Maintenance' started by COBBsoobyStage1, Apr 20, 2006.

  1. COBBsoobyStage1
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    COBBsoobyStage1 New Member

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    So, I'm thinking about getting the turbo back system from COBB since it will give me the performance I'm looking for without too much noise or the "Hey look at me" look. QUESTION: should I go with or without the cat? What's going to be the biggest difference other than the $150?
     
  2. 6MTizzle
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    6MTizzle 2SLO

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    I have the cobb and its quiet for an sti exhaust but not THAT quiet. If you go with the full tbe I would go catless since we don't have emissions. Catless I would imagine is quite a bit louder though.
     
  3. TSTRBOY2004
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    TSTRBOY2004 Well-Known Member

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    FYI - MInnesota may not check emissions but it IS A FEDERAL law so you can still be checked by the EPA.. not sure though if there are those guys running around MN??
     
  4. Imprezme02
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    Imprezme02 New Member

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    Catless is a little louder, and can smell if you give it some gas.
     
  5. Scuba Steve
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    Scuba Steve Well-Known Member

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    I've heard even the high flow cats MAY NOT pass an emissions test. I run with NO cats and stg2 cobb. My car is loud as heck, but that has everything to do with the Apexi N1 muffler section. A buddy is running the same set-up with the exception of an STi muffler section. His is much quieter and tolerable where mine shakes the ground and makes people want to run for cover!

    Cobb TBE is a nice system, but expensive, there are cheaper alternatives on the market that will give you the same results.
     
  6. COBBsoobyStage1
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    COBBsoobyStage1 New Member

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    Do you have any recommendations as an alternative to the cobb tbe?
     
  7. Scuba Steve
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    Scuba Steve Well-Known Member

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    You may want to check out clubwrx.net and go to the vendors/engine performance section. There are a ton of reputable vendors on there that list sales, and you should be able to strike a deal for a full TBE.

    Borla hush is just one great example of a soild exhaust with a tolerable noise level. And again, if you're buying the TBE....strike a deal!

    Also, there's a fair amount of people on that same site that have posted videos with the different sounding exhaust. Whatever you do take the time to do some research.

    FYI: If you're running cobb AP you might as well buy your up-pipe too and put that in at the same time....I didn't and later realized it was a big mistake!!! the dp has to come out when you install the up-pipe anyways so might as well do it all at once. (more importantly...my up-pipe cat didn't seem that secure in the pipe when I took it out. It freaked me out knowing a cat that could break apart was right before my turbo......yikes!!!)
     
  8. Imprezme02
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    Imprezme02 New Member

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    Bosal Twin Tip, like me and Fong!! obviously have to find a different downpipe, i dont suggest the bosal one.
     
  9. Scuba Steve
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    Scuba Steve Well-Known Member

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    and a bellmouth design.....
     
  10. esperunit
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    esperunit Well-Known Member

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    dang, you should have just getted you stock up pipe and put it back in and saved yourself some money and time. The aftermarket ones hardly make a difference compared to the stock gutted one.

    You can make your own TBE out of a cheap bellmouth DP like the ERZ/Helix and any catback you want. As for catbacks that arent loud, the borla hush and greddy evo2 are pretty much the top of the list.

    A high flow cat might not pass a sniffer, but it does pass visual tests that exist in other states that mandate straight off the bat that it needs to have a catalytic converter at least installed on the car. AFAIK in minnesota you can still be ticketed for not having cats even though we dont have inspections. I have heard of people being pulled over and hassled, and the cop puts the mirror under the car and writes a ticket.

    Also, my trunk STINKS like gas. the whole car smells like gas all the time. No cats here.
     
  11. Scuba Steve
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    Scuba Steve Well-Known Member

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    Looking back, would've opted to go with cats?

    regarding the up-pipe... you're right, I could've gutted it.....but I've never gutted anything before (lol) and i didn't want to mess around with the pipe before the turbo. and I must have shaved 1lb by going aftermarket...lol

    and there was no time savings for me... i had the up-pipe when I installed the dp....i was just to scared to do it at the time since I was doing the project solo...and for the first time...
     
  12. slavboy1
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    slavboy1 New Member

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    I'm running a CB Invidia G200 right now and soon will be Stage II with an Invidia V3 catless down pipe. With just the G200 it's a nice sound but it has a HUGE tip haha and i imagine with teh catless dp it's gonna get louder. I'll see if i can post an audio file and some picks when she's all said and done for ya just so you can have something to go on.
     
  13. kickin_81
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    kickin_81 Well-Known Member

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    All aftermarket exhausts are much louder than stock but the muffler is the peice to focus on if you're looking in differences of noise volume. Mufflers bigger in size will have more noise suppression material in it to better silence the noise (excluding the chamber-style flowmaster mufflers).

    In my experience, going from a catback to a catless turboback exhaust didn't make much difference in exhaust volume. They're both loud, dammit. I have a Bosal single tip catback and it's not as loud as a good number of aftermarket exhausts out there and only produces a little highway drone.

    My suggestion to you, "get whatever you want!"
     
  14. Musashi
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    Musashi Well-Known Member

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    I have seen some manufactures starting to make exhaust systems with the tip pointing downward to reduce exhaust noise. The lastest from Perrin is the duel pipe from the downpipe to the muffler. From experience, the more or better the glass packs the less sound output. So thats another feature you can look for when shopping.

    I have also wondered if wrapping the exhaust dp would make a difference!

    Happy hunting!


    Here ya go, this may be of some interest:

    http://forums.nasioc.com/forums/showthread.php?t=677926&page=1&pp=25

    http://www.turbomagazine.com/tech/0212tur_exhaust/
     
  15. Vila
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    Vila New Member

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    I went with a B&B TBE, no cats. I regret it a little bit. Exhaust smell has a hint of sulfur or something that it did not have before.

    Also, it would have been nice to not have totally dis-regarded the evironment. Gasoline is 6 pounds per gallon. So, in a 15 gallon tank, you have 90 pounds of fuel. The engines run at a 14.7 to 1 air-to-fuel ratio. This means you have pumped out 1,413 pounds of fumes with one tank fill! Not all of it environment un-friendly, but still.... If the cat could have been added at no extra cost, I would have got it.

    Vila
     
  16. bikerwriter
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    bikerwriter Well-Known Member

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    Catless exhaust smell all the time, especially when following behind them.

    But the main cat should be good enough for emissions purposes. In IL they only check to see if your CEL is on. On older cars they run the sniffer, and my dad's Camaro passed with a breeze, and he's running a Scoggin @#$%!@#$%!@#$%!@#$%!ey crate engine with full Edelbrocks. He just has a high-flow cat.

    The smell's the thing, and I for one would not want to live with it... :(
     
  17. esperunit
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    esperunit Well-Known Member

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    If I had built the car it would have catalytic converters. The smell gets on my nerves. My fiancee complains that when I drive with the windows down I always smell like gasoline.
     
  18. TSTRBOY2004
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    TSTRBOY2004 Well-Known Member

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    I built mine and it isnt loud at all.. I used a glasspack and a magnaflow muffler... it still has the rumble and some volume when on the gas but I dont even get second looks form the cops or the staties when I fly by them...
     
  19. Ripcurl007
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    Ripcurl007 New Member

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    I have a full perrin turbo back and i am running catless. I haven't heard the cobb yet but my twin tip system looks almost like the stock wrx exhaust the only time you know its not is on start up and looking underneath the car.
     
  20. Zola
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    Zola Well-Known Member

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    I definitely regret going totally catless. Not because of the environment, but the smell. It really is odious and I would hate to be driving behind my car. The high-flow cat wouldn't have been noticeably less power but would've made the passenger experience immeasurably better.
     
  21. jdmspecWRX
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    jdmspecWRX Well-Known Member

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    I have the Greddy Evo2.......looks super nice, very quiet.....low, rumble....wish it was a little bit louder.....but then again...it gets annoying over time.