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lalojamesliz
06-10-2012, 08:07 PM
hey guys whats going on, so i want to reduce the exhaust noise inside my all-trac and found this stuff http://www.amazon.com/Dynamat-10455-Self-Adhesive-Deadener-Xtreme/dp/B00020CB2S/ref=sr_1_1?ie=UTF8&qid=1339354770&sr=8-1&keywords=dynamat+extreme+bulk+pack
if i removed the factory sound deadener and installed this would it be quieter or would i have to put this over the factory stuff? my main goal is to quiet down the exhaust so i dont have to talk loud so my passengers can hear me plus i dont like the loud exhaust noise when my kids are inside. only the floor should need it right? thanks guys

Galcobar
06-11-2012, 01:01 AM
Dynamat is a sound deadener, which means it increases the weight of something to reduce vibrations or force them into a frequency low enough that we can't hear it. You'd apply it to something you want to stop vibrating, such as the panel in which you've mounted a speaker or a door panel you want to keep from rattling as you drive.

It will help reducing transmission of exhaust noise through the panels, but you might be better served by installing sound insulation. This is aimed at absorbing or blocking sound transmissions. The felt pad under the carpet and rear seats is an example of this, though of course not a terribly thick or effective one. People have successfully used household carpet padding to line their floorpan, side panels and even the headliner. You can also look into a product I and several others have used, which is a foam-and-foil self-adhesive product. Normally it's intended for duct insulation, but it's also what the FAA approves for use for noise reduction in aircraft. The foam absorbs noise and the foil reflects it. The usual source is a brand called FrostKing or Thermwell, available in most home improvement stores.

Quite a few people have actually used both products in their Celicas, applying the foam-and-foil to their panels and then a layer of carpet foam over top.

Aside from helping reduce all noise coming from outside the car, rather than just the car's vibrations, the other big advantages to the insulation approach are weight and price. Four rolls of the FrostKing/Thermwell will do pretty much the entire car and add perhaps 15 pounds. A single box of Dynamat or its equivalents will weigh in at 15 pounds or more. A roll of FrostKing costs only $18.

http://www.6gc.net/forums/index.php?showtopic=6198

joe's gt
06-11-2012, 06:34 AM
My brother has dynamat in his car and it was heavy as F*ck when he was putting it in. I'm sure there is much lighter substances that could absorb the frequencies and harmonics a lot better than by just adding mass. For me personally tho, the louder, the better! The 3s was made to roar. Its a very throaty 4 banger imo.

lalojamesliz
06-11-2012, 06:57 PM
Dynamat is a sound deadener, which means it increases the weight of something to reduce vibrations or force them into a frequency low enough that we can't hear it. You'd apply it to something you want to stop vibrating, such as the panel in which you've mounted a speaker or a door panel you want to keep from rattling as you drive.

It will help reducing transmission of exhaust noise through the panels, but you might be better served by installing sound insulation. This is aimed at absorbing or blocking sound transmissions. The felt pad under the carpet and rear seats is an example of this, though of course not a terribly thick or effective one. People have successfully used household carpet padding to line their floorpan, side panels and even the headliner. You can also look into a product I and several others have used, which is a foam-and-foil self-adhesive product. Normally it's intended for duct insulation, but it's also what the FAA approves for use for noise reduction in aircraft. The foam absorbs noise and the foil reflects it. The usual source is a brand called FrostKing or Thermwell, available in most home improvement stores.

Quite a few people have actually used both products in their Celicas, applying the foam-and-foil to their panels and then a layer of carpet foam over top.

Aside from helping reduce all noise coming from outside the car, rather than just the car's vibrations, the other big advantages to the insulation approach are weight and price. Four rolls of the FrostKing/Thermwell will do pretty much the entire car and add perhaps 15 pounds. A single box of Dynamat or its equivalents will weigh in at 15 pounds or more. A roll of FrostKing costs only $18.

http://www.6gc.net/forums/index.php?showtopic=6198

thank you for the great advice :) ill check it out right now

lalojamesliz
06-11-2012, 07:08 PM
My brother has dynamat in his car and it was heavy as F*ck when he was putting it in. I'm sure there is much lighter substances that could absorb the frequencies and harmonics a lot better than by just adding mass. For me personally tho, the louder, the better! The 3s was made to roar. Its a very throaty 4 banger imo.

i agree about the sound, i love the way it sounds and i think my kids do also but sometimes less engine noise would be better. like when my 2 yr old is sleeping or on long trips. sadly ive never heard my all-trac's exhaust from the outside at driving speed..... im sure me not letting anyone drive my all-trac has something to do with it :) im just happy i know it doesnt sound like a small honda

underscore
06-14-2012, 11:54 PM
Drive through a tunnel or between two tall buildings and give'r the beans and you will hear the beauty that is a 3SGTE

Hookecho
06-15-2012, 02:52 PM
When I had a flowmaster muffler the drone was horrible. So I went and got some of that polyester/cotton blended stuffing that is used in pillows or couch cushion. I filled up several small trash bags with. Then I stuffed them between the interior panels and body all throughout the trunk. Then I pulled my spare tire out, stuffed a bunch in the tire well, and set the tire back on top of it. Afterward I cut a thick piece of carpet to the shape of the trunk floor and laid it there. Then I placed the oem interior carpet on top. All of that reduced the noise by at least 50% or better. I eventually grew tired of any muffler noise at all and put an oem muffler from a Ford F150 on and now it's dead quiet.

4thgenceli
06-15-2012, 02:56 PM
I love that muffler

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Hookecho
06-15-2012, 04:51 PM
Which one?

4thgenceli
06-18-2012, 03:20 PM
Which one?

The one I got from you. Manaflow I think

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Hookecho
06-18-2012, 10:49 PM
You do like shiny stuff.

junctrac
07-01-2012, 04:08 AM
Ive gone through the same thing and even lined the whole floor and trunk with a layer of closed cell foam and 1/4" vinyl but honestly im still not happy about how loud the exhaust is when driving around town. So this time im trying to address the issue alittle more at the source by building resonance chambers on exhaust to cancel out where the really bad exhaust resonance kicks in. for me this is all that really bothers me is when it gets to droning really loud approaching 3 grand and up past 4. Anyway search about J Tubes or Helmholtz chambers lots of camaro and G8 guys have been welding them on and have had good luck eliminating the drone, just another option to think about. I may put a write up in the custom fab section once the tube gets in.

Galcobar
07-01-2012, 11:09 PM
The stock exhaust comes with a resonator -- unfortunately, the vast majority of items hawked by marketers as resonators are not resonators. A round-bodied muffler isn't a resonator, but they look alike from the outside. And since a true resonator isn't a sexy aftermarket piece, they're inexpensive and carried by just about any exahust shop.

A resonator is good for smoothing the tone and reasonable at reducing volume. The value is that by smoothing the tone and eliminating the more extreme frequency changes the noise becomes less noticeable, less annoying, and you more quickly get used to it. Volume reduction, without affecting exhaust flow efficiency, is best approached (can't be achieved but you can get close) with straight-through mufflers using smooth perforated interior pipes. The greater the length of the muffler, the more volume reduction. Resonators, on the other hand, only really need one in the system.

junctrac
07-03-2012, 05:31 AM
I agree with you but i think J pipes work alittle differently than a conventional resonator because there is no actual exhaust flow going through them only sound waves, so maby there more effective than a universal resonator? They have their own natural frequency based on geometry and when it corresponds to the engines frequency the waves cancel each other out. Thats the beauty of them there is the ability to tune out a certain rpm band that is obnoxious. Of corse this wont solve anything if its a 3" turbo back with only one tiny glasspack or something.

lalojamesliz
07-04-2012, 08:05 AM
A few days after I had my exhaust made I went back and had them install a glass pack because they told me it would quiet it down. It looks like a long muffler and it has fiberglass inside a jacket that goes all the way around. It worked but not as much as I was wanting it to work. I'm going to look into a resonator but their is no space underneath :(

Galcobar
07-05-2012, 12:06 AM
Glasspacks are 1950s technology and are deeply obsolete. They're a crude attempt at a modern straight-through muffler, but are significantly less effective at reducing volume while they introduce a great deal of turbulence to the exhaust stream, reducing exhaust efficiency and therefore usable power.

Modern straight-through mufflers use a smooth inner pipe with perforations, while glasspacks used louvered perforations. The insulation is also different. Modern designs use a ceramic mat, which is both better at noise reduction and longer-lasting than fibreglass. The mat is usually protected further by a layer of stainless steel wool wrapped around the inner pipe, making for a hardy design.

lalojamesliz
07-05-2012, 04:18 AM
Are resonators flow restrictive? A j pipe looks interesting but after reading around some V8 guys said it makes the engine sound weird?

Galcobar
07-05-2012, 05:17 AM
They're not restrictive -- a resonator is an echo chamber, the sound reduction is achieved by bouncing sound waves into one another to cancel them out, transforming the sound energy into heat.

I can see how some V8 guys would not be used to it, but a resonator is stock equipment on pretty much all engines these days. If you've ever heard a buzzy, annoyingly raspy exhaust note coming out of a car with an aftermarket exhaust, you can be all but certain they didn't include a resonator. Cars with V8s aren't known for smooth exhaust, but that's what a resonator is intended to provide. A resonator isn't really about quiet versus loud, it's more about pleasant versus annoying.

lalojamesliz
07-05-2012, 12:42 PM
Do you think this would help since its straight through? Or should a resonator have chambers?
http://www.amazon.com/gp/product/B001806YE2/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

Galcobar
07-06-2012, 06:25 AM
That's not a resonator. Resonators are echo chambers which cancel noise -- and therefore do not have a smooth perforated core wrapped in sound absorbing materials.

junctrac
07-07-2012, 03:18 AM
I have that vibrant ultra quiet "resonator" on mine it did way more than either of my magnaflows did ( one chambered and one 16" long straight through low profile one).