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Old 02-13-2015, 12:23 PM   #1
gasmn1620
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Re: what exhaust are you running?

my truck is at the exhaust shop right now. Getting it done from the manifolds back with flowmaster 40s. Not sure what it's going to sound like. Doing true duals.
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Old 02-13-2015, 01:01 PM   #2
homemade87
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Re: what exhaust are you running?

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Originally Posted by gasmn1620 View Post
my truck is at the exhaust shop right now. Getting it done from the manifolds back with flowmaster 40s. Not sure what it's going to sound like. Doing true duals.

It will be loud and have drone . If you like loud that's ok . But if not you may want to call them .
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Old 02-13-2015, 03:23 PM   #3
gasmn1620
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Re: what exhaust are you running?

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It will be loud and have drone . If you like loud that's ok . But if not you may want to call them .
I don't drive it every day and I'm ok with loud. No long distance driving. Can't be much louder than my Harley.
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Old 02-13-2015, 03:38 PM   #4
kevinr1970
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Re: what exhaust are you running?

I notice a few of you are going big pipe into muffler and then scaling down after; is there a reason for this?

Also, I have had FM's give drone, and some that didn't.
Would placement help with this?
If you had your mufflers as far back as possible, just before the pipe turns to go up and over the rear axle, so the mufflers are not directly under the cab.

I have a crew that needs exhaust and was planning on going with FM's...
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Old 02-13-2015, 05:09 PM   #5
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Re: what exhaust are you running?

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I notice a few of you are going big pipe into muffler and then scaling down after; is there a reason for this?
Flow/sound related for me. I wanted minimal flow restrictions leaving the motor & through the mufflers. After the mufflers the exhaust pressure drops so downsizing pipe size doesn't impact flow & it helps reduce the noise level.
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Old 02-15-2015, 06:45 PM   #6
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Re: what exhaust are you running?

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Originally Posted by kevinr1970 View Post
I notice a few of you are going big pipe into muffler and then scaling down after; is there a reason for this?
Much of the exhaust energy is given up in the mufflers, meaning a smaller pipe can be used after the mufflers with no loss of power. Very common for car and truck mfrs to do this.
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Old 02-13-2015, 03:50 PM   #7
rich weyand
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Re: what exhaust are you running?

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Originally Posted by gasmn1620 View Post
I don't drive it every day and I'm ok with loud. No long distance driving. Can't be much louder than my Harley.
It won't be that loud. There will be some drone, mostly at 40 mph constant speed. I have FM 40s on my DD, and it doesn't bother me at all.
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Old 02-13-2015, 01:37 PM   #8
Bigstevex4
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Re: what exhaust are you running?

Glass pacck dumped out in front rear axle Thank God its only a 6 banger. Resonates under box bad going to extend it out back soon.
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Old 02-13-2015, 04:17 PM   #9
gasmn1620
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Re: what exhaust are you running?

Just picked it up. Sounds pretty good. Quiet at idle and not super loud while driving. Sounds good.
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Old 02-13-2015, 09:02 PM   #10
77K10Silverado
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Re: what exhaust are you running?

What did it cost you gasmn1620?
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Old 02-14-2015, 01:37 AM   #11
05duramaxhd
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Re: what exhaust are you running?

flows only because I already had them
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Old 02-14-2015, 08:51 PM   #12
gasmn1620
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Re: what exhaust are you running?

$325. True duals with turn downs right in front of the axle.
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Old 02-14-2015, 09:36 PM   #13
outlaw1972
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Re: what exhaust are you running?

I have a mild 350 with pypes race pro mufflers with 2 1/2 in tubes running all the way out the back then turned down at the rear wheels on my 85 and they are nice sounding. No drone at all and they are nice at crusing speed, but sound mean when you get on it.
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Old 02-15-2015, 09:32 AM   #14
motornut
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Re: what exhaust are you running?

some pics
all pipes are 2.25
mufflers on the grass are dynomax turbos (78 C Burb)
others are cherry bombs (78 K Jimmy) and Flow masters(79 C Jimmy)
the 78 K now has the turn downs after the bombs
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