A few people said they go bad in a few months but what does that even mean? Are they just stupid? And what would cause a glass pack to go bad?

 

I've never had one "go bad."
They change their exhaust note over time as the (glass brakes up. ) assumption.
I'm not even sure if it's really glass. Or if it breaks up or just wears.

 

Do you think it sounds bad once that starts to happen? And do you think I should straight pipe it or use the glass pack?

 

And thanks for the advice

 

I love straight pipes. But I also like the sound of glasspacks. It's all personal preference. Look up Toyota glasspack or just glasspack on YouTube. Hopefully you can find a Video that the wind isn't too distorted

 

Found one.

 

Straight pipes sound great, but they're SO loud! My 4Runner is loud enough with no cat and a flowmaster 40 series and well... let's just say there's no way in hell that I'm sneaking up on anyone

Do glasspacks go bad? Yes. Do they go bad in a few months? No. Glasspacks do wear out, but it is over an extended period of time and all that happens is that they get louder (from what I understand).

Glasspacks do sound sick on the 20R's and 22R(E)'s though!

 

Agreed. My 79 has a header and flowmaster 40 that I swear is gutted. VERY loud. I turn it off to talk to people at my passenger window

 

The first time I did my exhaust I straight piped it and shot it out the side sounded awesome but it was a bad job so I redid it and shot it out the back but that was too quiet, I just put the glass pack and now it sounds deeper but it doesn't crack like it did the first time I did it.

 

I am curious what is the appeal of having a loud exhaust??

It really does nothing but make noise.

 

I like hearing my engine. Not necessarily loud. I like a nice exhaust note and a bit of .... welll its not a word but , throaty-ness.

 

Same here I guess it isn't mainly the noise, I just want to hear the engine. When I put a muffler on it, you can't hear anything or it all just blends together, I like to know I'm running on the only four cylinders I've got. I enjoy the throatiness. I mean it sounds good with the glass pack but like I said, it blends it up so you can't hear the individual cylinders. I've also noticed that the short 2" exhaust I put on it the first time had a lot better flow than the stock sized 1-1/2" that I later tried and the glass pack I put on it a few hours ago.

 

glasspack muffler is basically a straight perforated tube with fiberglass matting (similar to insulation) packed around the outside of it. reason why you want one on your pipes vs straight-pipe is that it will remove certain frequencies from the exhaust note. glasspacks come in different lengths which will also effect sound since the exhaust has more contact with the matting. the glass matting inside will degrade with time, but if it's going faster there could be a reason why - like inefficient burn causing hot exhaust. when they break down, the exhaust note changes and is usually described as "louder" - but it's more of a frequency thing as well since you no longer are eliminating that high frequency that the matting was removing before.

a "turbo" muffler is almost the same as a glasspack, it's just larger diameter so it can hold more matting around it, giving a slightly quieter sound yet flowing the same. flowmaster mufflers don't use matting inside, they divert the exhaust through metal baffles which in turn change the frequency as well, at the expense of sounding "tinney" on certain engines; since they are not a straight-shot through the muffler they technically are more restricting than a glasspack or other straight-through mufflers.