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Unread 02-01-2010, 04:59 PM   #1
TheDude584
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Intake and new muffler = worse gas mileage?

I put an intake and a thrush turbo muffler on my 05 wk 3.7L. my gas mileage has gone from about 16.5 ish to a constant 13.8. I was expecting opposite results.. any ideas? (I understand its a jeep and not a prius, im just wondering)

*** Thrush Turbo is too loud btw. I dont recomend it.***

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Last edited by TheDude584; 02-01-2010 at 05:01 PM.. Reason: Thrush bash =)
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Unread 02-01-2010, 05:24 PM   #2
GCL06
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Might just be a heavier foot? I've been having too much fun with the new power on ice haha. Not sure what kind of air restriction the turbo might have but that could also factor into things. The filter on your CAI might not be breathing very well (I like my Spectre).

Not to jack the thread but if it's possible I'd love to hear a sound clip of the turbo
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Unread 02-01-2010, 07:14 PM   #3
Lt_JWS
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Have you factored in the new tires and the size difference? Leave anything unhooked? Has it been colder then usual? Did you install the muffler yourself and was it new?
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Unread 02-01-2010, 08:10 PM   #4
smcginnis87
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if you don't have enough back pressure you can run the possibility of getting worse MPG.... only really in turbo cars the bigger and more air out the better.... but yet it could be that you have a lift ect.
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Unread 02-01-2010, 08:12 PM   #5
JMorash
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was it a weld in muffler, or was it a kit.
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Unread 02-01-2010, 08:19 PM   #6
GCL06
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Quote:
Originally Posted by JMorash View Post
was it a weld in muffler, or was it a kit.
My Thrush Welded was a weld in; I'd assume the Thrush Turbo to be the same.
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Unread 02-01-2010, 10:07 PM   #7
Devilsmed98
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I say heavier foot.
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Unread 02-02-2010, 06:07 AM   #8
falcon10
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All the above possibly or winter fuel?

With winter fuel my mpg drops 2-2.5 mpg
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Unread 02-02-2010, 08:05 AM   #9
tjkj2002
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Quote:
Originally Posted by smcginnis87 View Post
if you don't have enough back pressure you can run the possibility of getting worse MPG....
Correct,the 3.7 likes back pressure.

Plus the AEM/K&N CAI are not CAI kits,there HAI kits(Hot Air Intake).
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