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glass pack muffler

the right glass pack(or wrong depending on how you look at it) can make even a 2cyl. sound like a V8! so it depends on if your going for sound, performance, gas milage. just figure out what your wanting a "muffler" for then decide on what to use. unless you want loud sound for cheap then grab a glass pack, stick a water hose in it to shrink the fiberglass and it will make it even louder!
 
One thing to consider is that when the paint chips off them they will begin to rust fairly quickly. If you get a glasspack get one that is aluminized.
 
in my opinion just throwing on a cat back really dont do all that much unless you have reason to throw out more air! i.e. intake, bored TB and spaser to suck more air, cam to help put the more air to use and add more fuel to the air, thus creating more combustion(pressure) all new ignition to burn that gas faster and better to make pressure, then a header high-flow cat and new cat back to shuv all that air out which = more power, torque and a GREAT cound when all combined! so if you just want sound go for it if you want power start with a header then go from there!
 
when i put my first cat-back, while merging on the freeway at full throttle, it did help it a little. It was noticeable. I'm just checking to see if there is any reason why the glass pack would reduce that or lower my mpg? I dont think there is, but im just checking to see people thoughts. Thanks
 
i bought a Thrush glass pack for $20 @ advanced auto and i dont think it sounds too bad.. its not loud it just gives a nice growl... although you will have to fab some thing to make it fit because the stock muffler is off-set
 
gone one for free acouple years ago, its loud but so is the huge hole in my exhaust manifold, once i replace the header i will be putting my stock muffler back on
 
i have a cherry bomb glass pack and a 9 inch k and n filter. When i added the glass pack i noticed a loss in horsepower. It was right after i lifted it and i thought it needed to be louder to match the apperance. it is louder but that is the only thing good about it. I noticed a loss in throtle response most of all. When these people say back pressure is good, they know what they are talking about. Some day I will get a 3 inch dual oulet flowmaster
 
Keep in mind that glass packs aren't considered spark-arresting mufflers because of their straight-through, unbaffled design. If you do any driving through state or national forests, you have to have a spark-arresting muffler. I was going to get a glass pack, but I go off road mainly in Michigan, and they will check to see what I'm running.
 
My borla exhaust is also straight through, I can hold up the muffler and see straight through the other side. What actually prevents the sparks is the perforated inner tubing, which also helps the sound dampening. The reason "glasspack" mufflers are usually louder is because there isn't as much insulation to abosorb the sound. I'll do some testing with it to make sure there are no sparks, IF I see a slightest hint of sparks, I will definately take it out as to be safe and help prevent forest fires. Frazier park is still closed due to the fire. Thanks everyone for the input, well appreciated. I'll post up my thoughts after installation.
 
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the no cat is where the loss of power comes from, as it produces the required backpressure needed for the engine. And the fact that it drops right before the axle contributes to the extra cab noise. Ya when i had to re weld my down tube to the flange, i drove it around the block without any exhaust, just headers and it was WAYYY too loud, and I did notice a little big of a loss in power, but I couldnt' test it fully because the noise was too loud, and I didn't want to bother my neighbors.
 
I have the dynomax cat-back with a high flow cat. I noticed a little preformance difference, but not much, not enough to brag about. I was kinda dissapointed with the sound, I was going for a throughter roar and got a mid-pit humm. Kinda made me think of a ricer. As soon as I get the money, and after my the extra lift, im gonna get the flowmater 40 series.

just my 2 cents.
 
Timber said:
Keep in mind that glass packs aren't considered spark-arresting mufflers because of their straight-through, unbaffled design. If you do any driving through state or national forests, you have to have a spark-arresting muffler. I was going to get a glass pack, but I go off road mainly in Michigan, and they will check to see what I'm running.
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as long as you have something in your exhaust that is not straight through (which i have a cat still) you will be ok with the wheeling in michigan.
Btw i have never seen anyone be checked for exhuast (besides fourwheelers) but i did read that on the rules list for silver lake. Also i am NOT saying glass packs are good and you should get one Because they are not. They are nothing but a cheap way to make it louder im my opinion. I dont like mine at all but I have better things to spend my money on right now (ie fixing leaks)
 
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I bought my glass pack because:
* super cheap
* thick outer shell, so it is more dent resistant in the rocks
* smaller profile, so it doesn't hang down as much, and less to get caught up in the rocks

I noticed a slight loss in low-rpm power, but it revs up quicker and is faster on the street.

The sound isn't that great, but I have yet to hear an I6 that sounds "cool".
 
ArcticCat843 said:
as long as you have something in your exhaust that is not straight through (which i have a cat still) you will be ok with the wheeling in michigan.
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Well, that might be your experience, but I came out of a trail (a "route" in Michigan--specifically Gladwin) and was stopped within fifteen minutes in 2002. The DNR officer checked for mud (which is apparently illegal to have on your vehicle in Mich.) and he checked my exhaust system to see if it was legal.
 
Timber said:
Well, that might be your experience, but I came out of a trail (a "route" in Michigan--specifically Gladwin) and was stopped within fifteen minutes in 2002. The DNR officer checked for mud (which is apparently illegal to have on your vehicle in Mich.) and he checked my exhaust system to see if it was legal.
Click to expand...
Did you have a cat?
I have never had a first hand experience with the DNR checking me but i was told that when you go to silver lake as long as you have someting in you exhuast that is not wide open you are ok. I could be wrong. That just gives me another reson to go to a flowmaster.
I dont really understand what you mean when you say "checking for Mud" They acually pulled you over to check for mud? or was it something like they wanted to make sure you could see out your windows? either was that is stupid and you would think they would have more important thing todo.


After google searching gladwin, i think i have been on some trails there before.
Is there a big sand hill called Bull gap there?
 
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