Author Topic: Muffler or no muffler... That is the question  (Read 4865 times)

Offline zieg85

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Muffler or no muffler... That is the question
« on: September 12, 2017, 03:50:04 PM »
OK, I have the original exhaust system on my 2001 Chevy 2500HD with a 6.0L.  My muffler is starting to rust out and has had an internal rattle since I got it.  On a few trucks with catalytic converters I've just put a pipe in place of a muffler and really liked the sound.  I didn't notice any decrease in performance but I tended to get better mileage simply because I took it easier knowing that if I drove it normally I would draw allot of attention.  This truck has a massive 2 in and 2 out single muffler and looks like it would be very pricey to replace.  Would a lack of back pressure cause the OBD II to flip out.  The only 2 trucks I have ever done this to was a 95 with OBD I and an old 82 with no computer.  Thanks in advance.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline VileZambonie

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Re: Muffler or no muffler... That is the question
« Reply #1 on: September 13, 2017, 06:59:06 AM »
I couldn't tolerate the drone especially when the harmonics come together. I would definitely run a muffler.

If you are looking for something inexpensive, get an eBay special.
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Offline roundhouse

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Re: Muffler or no muffler... That is the question
« Reply #2 on: September 13, 2017, 08:46:29 AM »
A cheap glass pack will knock off the drone

Just a cat and no muffler will drill thru your head after a half hour

Offline zieg85

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Re: Muffler or no muffler... That is the question
« Reply #3 on: September 13, 2017, 09:02:46 AM »
A cheap glass pack will knock off the drone

Just a cat and no muffler will drill thru your head after a half hour
2 inlets and 2 outlets... hmmm, I guess side by side straight through glass packs would fit.  Great idea.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline BlackTomC

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Re: Muffler or no muffler... That is the question
« Reply #4 on: September 13, 2017, 09:40:09 AM »
Your truck would sound like this, granted mine has headers and cats installed, with 3 inch pipes (with an x pipe), no drone.

https://www.youtube.com/watch?v=3Hw7PM4NnUk

Loud as heck.

I put series 10 mufflers back on it, couldn't stand how earth shatteringly loud the exhaust was. (This was before regearing from 3.73's to 4.56's so it was loud and SLOOOOWWWWW).
The bottom line has dropped

Offline zieg85

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Re: Muffler or no muffler... That is the question
« Reply #5 on: September 13, 2017, 10:37:49 AM »
I couldn't tolerate the drone especially when the harmonics come together. I would definitely run a muffler.

If you are looking for something inexpensive, get an eBay special.

Found this, now to shop to see if I can find someone who can weld it in for me before I buy it
http://www.ebay.com/itm/00-07-Chevrolet-GMC-2500-6-0-8-1L-HD-Muffler-3-Dual-in-Out-Single-Tail-2500/263172658047?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline Grumpy Owl

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Re: Muffler or no muffler... That is the question
« Reply #6 on: November 08, 2017, 05:05:37 PM »
Would a lack of back pressure cause the OBD II to flip out.

I know the topic is a little old but I didn't see where this question was answered or whether or not you got your muffler installed.

The back pressure will not affect the OBD II.  Its the downstream O2 sensor that will cause a check engine light to come on if you remove or gut your cats.
1986 Silverado

Offline zieg85

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Re: Muffler or no muffler... That is the question
« Reply #7 on: November 08, 2017, 06:48:44 PM »
Would a lack of back pressure cause the OBD II to flip out.

I know the topic is a little old but I didn't see where this question was answered or whether or not you got your muffler installed.

The back pressure will not affect the OBD II.  Its the downstream O2 sensor that will cause a check engine light to come on if you remove or gut your cats.

Still haven't gotten this done.  Been thinking dual glass packs replacing the 2 in 2 out muffler.  Just need to find the right length and it is something I think I could do if the muffler shop quotes outrageously high
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline Grumpy Owl

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Re: Muffler or no muffler... That is the question
« Reply #8 on: November 09, 2017, 07:33:04 AM »
If you order the correct mufflers ID and length, you could always use clamps in a pinch till you get them welded. 

I personally use a lot of summit brand mufflers.  They sound good and are priced cheap.  Usually around 30 bucks each.

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1986 Silverado

Offline Captain Swampy

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Re: Muffler or no muffler... That is the question
« Reply #9 on: December 07, 2017, 11:40:42 PM »
We put a 12568 Magnaflow on Brooke's truck. It has an internal X pipe. I really like it.
1987  350TBI 700R4  4X4  4.56 gears  33" BFG All Terrain


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Offline Irish_Alley

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Re: Muffler or no muffler... That is the question
« Reply #10 on: December 09, 2017, 10:36:34 PM »
i know youre not up for the cat removal but they do make O2 sensor simulators which just plug and play and make your ECM think its seeing the right about of air passing. or you could do an spark plug non fouler trick. found HERE
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Offline zieg85

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Re: Muffler or no muffler... That is the question
« Reply #11 on: July 20, 2018, 06:32:22 PM »
Well I got tired of the muffler rattling internally so I took it in and had a pair of Flowmaster's put on it.  I couldn't be more pleased.  Doing 65 you can barely hear it and it has a nice low rumble about 1500 rpms.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/