exhaust system Q's From the noobie...

Discussion in 'Engine & Performance Modifications' started by elders05srt, Sep 7, 2009.

  1. elders05srt

    elders05srt Full Access Member

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    *******what is listed below is not scientific only an observation*******
    http://maxxfab.com/welcome.html http://www.modernperformance.com/dcx...borla_dyno.jpg
    https://www.modernperformance.com/dcx/product_release/aemsrt4dyno.jpg

    Here are Maxfab's dyno run results as well as MPx and AEM's...
    MaxxFab test their Full 3" turbo back against their 3" o2 housing and down pipe w/ Borla cat back and the results; a difference of 0.8 hp and 3.4ft lbs. from that result I could not really tell you if it makes that BIG of a difference. Now granted i only changed the down pipe and not the o2 housing. Not even a big gain on MPx results on Borla cat back vs. the Full 3" turbo back from Maxxfab. 7hp & 6.8ftlbs just the cat cat back vs. stock exhaust with MPx dyno. So I think that it comes down to a matter of opinion in some of these cases. My pipe bolted right up. No fitment issues. Like I tell my customers "you should buy what you like". and besides dont you want a little bit of back pressure? but like i said i Bought the mopar one because i liked it the best Not to say that other ones aren't "better". I felt this set up was most efficient. not the "If a 3" exhaust is good then a 4" must be better" idea.

    (this is only for comparison as these are 2 different cars (w/ like parts) and dyno's.)
    (note how close the base line runs are between these 2 dyno's.)

    MPx car Stage 1 w/ Aem
    stock - 230.7hp 246.ftlbs
    cat back - 237.7hp 252.8ftlbs

    7hp & 6.8ftlbs just the cat cat back vs. stock

    maxxfab car - stage 1 aem, stock boot
    stock - 231.3hp 251.2ftlbs
    Full 3" turbo back - 242.1hp 263.1ftlbs

    11.2hp & 12.1ftlbs Stock vs. Full 3" but only
    ~5.6hp & 11.7ftlbs 3" vs. Borla cat back.~
    (MaxxFab car Did have more Ftlbs to start)

    maxxfab car stage 1, Aem, AGP waste gate actuator @ 18 psi.
    3" w/ Borla cat back- 266.2hp 301.8ftlbs
    Full 3" - 267.0hp 304.4ftlbs
    .8hp & 3.4ftlbs 3" to 2 1/2" vs. full 3"

    So what do you think? i am not saying any one system is better. i would just like to see every ones view point. Do o really need a full 3" turbo back system on the ---stock turbo? or would a 2 1/2 system make close to the same power? :thanks:
     
  2. kingnate

    kingnate Full Access Member

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    turbo back > cat back

    If you are planning on ever modding the car why not just do the full turbo back. Its doesn't cost that much more and it saves you some trouble in the future.

    I would suggest you decide on what modding path and what goals you have for your car and then ask this question.
     
  3. Goats

    Goats God of skittles

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    A 3" turbo back is the way to go and that includes the 02 housing on a stock turbo and the sad news is maxx fab is no longer making exhaust but I like the MPX better anyways
     
  4. elders05srt

    elders05srt Full Access Member

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    i have the full 2 1/2" Mopar kit on my car. but my question is how much better is a full 3" then the 2 1/2" mopar? (stock turbo)
     
  5. elders05srt

    elders05srt Full Access Member

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  6. Quick

    Quick Mgmt. - I can't help you

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    I think you're right on that last point. but it depends.

    On the stock SRT8's the Mopar/Corsa is 2.75" all the way through. The other aftermarket cat backs are 3". The Mopar/Corsa makes more power on a stock car. Bit I'm sure it depends on whatever else you've changed.
     
  7. 2muchpsi

    2muchpsi Gold Supporting Members

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    i am also running the mopar downpipe with borla cat back. the borla was on the car when i bought it and my buddy gave me the downpipe. i am still on the stock turbo also
     
  8. kingnate

    kingnate Full Access Member

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    You are right it is only going to move so much now the real question is are you always going to stay stock turbo? If you plan on ever going to a larger turbo then you are going to want a larger exhaust.

    Yes mopar engineers are smart but they have to worry about things like emissions etc so they are very limited in their designs.