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Old 02-09-2010, 04:24 PM   #1
blazer2007
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full length exhaust vs fr. of tire noise level

I have a 80 s.b. with dual exhaust dumping out in fr. of each rear tire,was wondering would full exhaust out to the rear bumper be that much quieter,wife says is loud and she won,t ride her bike in the cold lol.Is all new mufflers etc,is 2/14 pipe and basic turbo mufflers
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Old 02-09-2010, 04:30 PM   #2
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Re: full lenght exhaust vs fr. of tire noise level

Probally would be quiter, I had a 91 with true duals with just glass packs, I had turn downs in front of the axle. It was way louder then when I had it dumping out the rear.
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Old 02-09-2010, 06:09 PM   #3
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Re: full lenght exhaust vs fr. of tire noise level

had duals with turn downs to dump before the tires in my 78 and i liked the deafing kinda rumble but could'nt talk or hear the radio.put pipes to the back,much quieter but still have a rumble........
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Old 02-09-2010, 06:38 PM   #4
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Re: full lenght exhaust vs fr. of tire noise level

It will be significantly quieter going out the back. it tends to echo under the bed when dumped out the side or in front of the axle
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Old 02-10-2010, 10:05 AM   #5
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Re: full lenght exhaust vs fr. of tire noise level

It will be quite a bit quieter. Add in a X-pipe or H-pipe and it will quiet down a little more too.
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Old 02-10-2010, 02:06 PM   #6
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Re: full length exhaust vs fr. of tire noise level

I got super turbos dumped right behind the rear wheels and is not so loud.
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Old 02-10-2010, 02:28 PM   #7
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Re: full length exhaust vs fr. of tire noise level

My exhaust used to dump out the back. After I lowered it, I needed to change things for clearance. I did new pipe, mufflers, etc dumping out in front of the rear tires. It is louder in the cab now because you sit closer to the exhaust outlet. And even if I had kept with the same mufflers, it would surely be louder outside the truck too. Anytime you can lengthen the exhaust pipes, you will mellow out the tone.
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Old 02-10-2010, 04:49 PM   #8
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Re: full length exhaust vs fr. of tire noise level

Straight out the back is significantly quieter than anything out the side. Side exit also tends to echo off the barriers on the sides of the lane, back into the truck.

I did notice a bit of improvement with side exit exhaust when behind the tire vs. in front of it.

On my lifted 4x4 with side exit pipes behind the tires, I put a set of mud flaps on it & it actually made the truck quieter by blocking some noise.
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Old 02-10-2010, 05:47 PM   #9
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Re: full length exhaust vs fr. of tire noise level

I've had 3 dual exhaust systems on these trucks and here is my take:

Full length headers, 3" 40 series flowmasters (2 chamber), no crossover side exit behind the rear wheels, long bed. Loud, substantial interior resonance, good pop but not too harsh.

Factory manifolds, 2" +/- short glass packs no crossover, straight out the back, short bed. Loud glass pack crack, not as loud in the cab as out, but still quite a bit of noise while cruising.

Currently full length headers, 2.5" 50 series flowmasters (3 chamber), summit h-pipe, side exit behind the rear wheels, short bed. Really deep but mellow sound. Not too much resonance at all while cruising. I haven't gotten after it since I got this installed (less than a month ago) because it has been pretty slick out, but I like it a lot. I've noticed my wing windows whistle, and I never noticed with the glass packs.

Exhaust note is very subjective, but if you are trying to quiet it down and mellow it out on the cheap I would add an h-pipe and extend the exhaust to the rear, either straight out the back or behind the rear tires. I prefer behind the tires on old trucks but again to each their own.
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Old 02-10-2010, 09:59 PM   #10
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Re: full length exhaust vs fr. of tire noise level

Mine was dual 3" with 3 chamber flowmasters (I forget the series), but it had a built 427 in it, which upped the noise significantly.

Originally I ran it with no tailpipes, which I think looked & sounded better, but had quite a bit of interior resonance.
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