Hi Guys! As you may recall, I got a 2004 Jeep Grand Cherokee Laredo 4.0 6cyl about a month ago. The week I got it, I put a 'Holley (Flowtech) Afterburner muffler on 13", Stock was 31" so I had to add pipe. Now I purchased a 'Thrush Glasspack' to replace it. (It is 31" just like the stock, so I can get rid of the extra pipe I needed to get to compensate for the difference in length.) As you may recall, I like it LOUDer than stock (as I put a 'Thrush Turbo on my 2006 HHR LT 2.4 when I had that.) Does it make a difference if the Glasspack is longer or shorter in length for sound? Will it be louder, quieter, or no difference at all? Being that it is the same size as the stock muffler, I decided to purchase that one so I could get rid of the extra add-on pipe I needed to get for the existing muffler I put on, it seems to be 'leaking' from the seems that were only clamped on since the pipe-fit seemed tight. Since it wasn't I put some 'quick steel' around the joints & that took care of the gaps. I know you will think I am being a 'LOON', but I like what I like, & I like it more-than-noticeable & different than the dozens of Jeeps that are the same as mine in my area. I would Like to hear your comments, whether they be Pro or Con on mufflers. I am just looking for some advice and input on your ideas/experiences on this. I plan to get it put on within a day or two anyway, but would like to know more about the length of the muffler I had asked about, just so I know what to expect. Thanks Guys, & Hope to hear something back from you soon! As I was told, I could come back & ask anything I wanted even though I no longer own an HHR, so I am taking you up on that offer! You guys ALWAYS gave me the Best advice & understood my 'craziness' when it comes to mechanical issues!

 

IIRC, aren't glasspacks used in addition with a muffler?

 

They can be used that way but not always...... some guys use them as the only muffler.

 

Any ideas on my inquiries? BTW, nice to hear from you again!

 

I really don't know what it's going to sound like, glasspacks tend to sound okay at first and get rapidly loud and raspy as the glass burns out..... They also rust out pretty quick. Turbo mufflers tend to be a better sound in my opinion.

 

The 'Thrush Turbo' I had on my HHR sounded more like an exhaust leak than a performance sound type muffler. (Of course that was a 2.4L 4cyl.) What I have now is the Red Powder-coat finish that is Supposed to stand up to time, & Not rust too soon. As for the 'raspy' sound, would, or should I ask DOES an exhaust tip make any difference in sound? I was told by some that they Do, & some that they DON'T. IF they DO, would that help the raspy sound if I have a resonator tip? If they DON'T, Why are tips so widely varied in price, besides the name. (I have the stainless steel with resonator insert.) And why the plain metal tip & the one with resonator insert?

 

An actual resonator should help some but are probably more effective before the muffler than after. Some "resonator" tips, the cheaper ones, are nothing more than a tip with a fancy name..... You get what you pay for there. 4 bangers are hard to make sound good via exhaust mods..... I really haven't heard anything that didn't sound like rice, or worse. But that's just me.

 

This may sound silly, but I was told the resonator tip would 'amplify' the tone coming out, & another told me the same you did. I don't quite exactly understand the whole resonator concept, but I do know that with all the 'auto parts "experts" advice', they ALL got me confused on what it does, what it doesn't, what it should, & what it shouldn't. You guys are the ONLY ones that give me straight answers that help me understand more.

 

A true resonator should muffle "resonant" frequencies through a cancellation technique from my understanding of them, and those frequencies are normally heard as raspy..... It doesn't muffle them or remove them but it smooths them out. This may be what someone might mean when they say "amplify" but that's a misuse of the term amplify.

Some guys use glasspacks as resonators, thus XtremeSS's post above. This would usually be before a standard muffler..... By themselves they tend toward loud and as I said earlier once the glass burns out aren't very effective.

 

Thank You Very Much for clearing that up for me. Now I understand a bit more about the resonators. I do tend to like it to be louder, so did I make the right choice in the glasspack?