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aftermarket muffler problem

Discussion in '2011-2014 V6 Mustang Tech' started by summerscheifer, Jan 6, 2011.

  1. summerscheifer

    summerscheifer New Member

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    i have a flowmaster super 44. i have noticed a slight decrease in power and maybe mpg?? the thing that ive noticed the most is when i am a cruising speeds at about 60mph the rpms are at about 2k.. is this normal?? is it aftermarket muffler?
     
  2. JRK

    JRK Well-Known Member

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    lol it's all in your head. The RPM's won't change from a different muffler. If anything you'd get more power and better gas mileage.
     
  3. sircrashalot

    sircrashalot Caribbean love 2 eat rice

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    lloll what wrong with being at 2k at 60mph, i am at 2000 at 70mph in a 3.8 and you have 6 speed tranni so i think that perfectly normal
     
  4. boss302man

    boss302man Active Member

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    what size pipes do you have? IIRC 2.5 will decrease HP slightly, unless you have F/I. 2.25 is stock size and should give you more power, if any.
     
  5. JRK

    JRK Well-Known Member

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    :confused: He never said what transmission he had. Where'd you come up with a six speed?
     
  6. yodman

    yodman Switching it up

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    What kind of car are we dealing with here is the question? 3.7, 3.8, 4.0, auto, manual, single exhaust, dual exhaust? Do tell, because I'd like very much to help point you in the right direction.
     
  7. mike6187

    mike6187 New Member

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    in my experience, i can say it is a failing muffler when there's a change in the sound of your car when it starts and while it is running. You might not notice it at first but it will sound louder and if it is not repaired the sound will definitely get louder and louder. When a muffler is bad, gas mileage is seriously decreased.
     
  8. silver6stang02

    silver6stang02 Keepin' it real

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    They are 2.5 from the factory on the stock 3.7.....hp won't decrease with bigger piping....it moves higher in the rpm band.

    He has a 2011 3.7....they come with 6speed auto's AND manuals ;)
     
  9. silver6stang02

    silver6stang02 Keepin' it real

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    Your problem is probably in your head, You may feel an ever-so-slight difference in backpressure resulting in a MINUTE loss in tq at that particular RPM.