Has anyone else installed the "new" ZZP catback kit which now apparently includes a Magnaflow resonator instead of the Whisper resonator? The website still says "Db level same as OEM with resonators" but I'm having a hard time believing that is still the case. I just got my car back from the shop, and it is just ridiculously loud and drones like crazy. It's nice under throttle, not my cuppa tea at speed.

Anyone have any suggestions for a muffler that might make the car at least drivable? Maybe I'll just buy that then and have ZZP weld it in since it might have to go back anyway. Whole thing is sticking out the back of the car 2 inches right now too. Have to check the shop's work, but I'm guessing I might have got Cobalt length instead of Redline length. Of course, ZZP had it ready for me in a day so I can't complain too much.

UPDATE: Just got back from ZZP and they took great care of me today. I bought one of the new Dynomax VT mufflers and brought it to them for installation. They whacked off the crappy Magnaflow and band clamped the new muffler into place. The exhaust is also a little shorter now as well. Not quite flush, but more acceptable. The noise issues are gone, and the car purs like a kitten. I'll post about the new muffler in a separate thread, since anyone with a loud exhaust who is tired of having their brains rattled out needs one. Now. Best. Muffler. Ever.

 

Add another Muffler/Resonator...

...that should quiet it down.

 

the cobalt is 2" shorter then the ion but talk to zzp about it i'm sure thye'll work with you and help out

 

Haha funny how you can say you can't complain 'too much'... They gave you the wrong exhaust. No complaints there LMAO... /sarcasm

 

Like I said, I'm not sure the exhaust is the issue with the protrusion too far out the end. It might be the assembly job by the shop. I've got to take a look at the hangers and figure out why it isn't quite right. I do have to deal with the muffler issue though. Is there any muffler anyone has had that is substantially quieter than the norm?

 

After a bit more research, I've had to come to the unfortunate conclusion that basically, this package as it exists today was not a terribly well researched or put together package. It isn't something anyone should buy and expect to be happy with. Their old system was great, from most accounts. This new system is fancy polished trash that would have ruined them if they're tried to unload it a couple year ago when catbacks were still flying off the shelves. It's that bad.

First, let's be clear about one thing: A resonator is just a muffler with a silly name attached to it. It ain't nothing special. Well, except in one respect: A resonator is largely supposed to cancel out the frequency of sound that causes drone. This is normally achieved through reflective sound cancellation, because other technologies have a very difficult time attenuating lower frequencies to any significant degree. (In some cases, a resonator might simply be used to smooth out or attenuate the overall exhaust. In those cases, there will then normally be some sort of cancellation in the muffler itself, if that is necessary).

I don't have the specifications, but based on the allegation that the Whisper resonators would "come apart" in some early units due to weld issues, I assume they were actual baffled resonators, versus a simply straight through perforated tube with packing.

A perf tube with acoustic packing, on the other hand, has very little ability to cancel out the low frequency "drone" noise. While it might look like a resonator, it doesn't do--and is not designed to do--what a "real" resonator does.

What ZZP is selling for their catback now is a Magnaflow oval perf tube glass pack muffler with another Magnaflow round perf tube glass pack muffler (PN 12867) that they're fobbing off as a resonator. Once I actually ran a search on the part number and saw that this thing was NOT a resonator (nor does Magnaflow advertise it as such), this all made sense. Basically, ZZP has two identical muffler technologies (since they also use an oval Magnaflow muffler), each of which does next to nothing to cancel out drone. You would need a much larger chamber to even have a chance at it. They selling an exhaust with two straight through perf tubes one after the other.

With a 3" catback system, having two relatively short, straight through glass pack mufflers isn't going to work well even in theory, and it certainly doesn't in practice. I finally took a longer drive in the car with some passengers, and they were seriously pissed off by the time we arrived. Our heads were throbbing, and the universal sentiment was that my exhaust sucked. I have to agree: This setup is a joke. This was an example of throwing random parts into the stew and hoping something acceptable would come out. It didn't.

The shame of it is that there are about $250.00 worth of mufflers on this thing, and I'm going to have to eat a big chunk of that in order to replace them because ZZP didn't do their homework before selling a system that does NOT do what it is advertised to do. I particularly dislike beating up on a local company (particularly when I'm bringing my car back to them for more work), but in this case, it's well justified. They should not have called a glass pack muffler a "resonator" when it isn't. Nor should they continue to claim that the decibel level are the same as factory levels when they are not.

Hopefully, they'll make this right by pulling my exhaust welding a REAL resonator. Else, it's going to have to go back for a refund, because it is not drivable, and for the cash it's going to take to make it drivable, I could have bought a Corsa.

 

I have zzp's catback w/o a res. and I love the sound of mine

 

Everyone should know by now that there is not such thing as a quite 3" cat-back. They don't exist.

 

Maybe on the lsj they dont exist

I have catless dp and a 3 inch catback w/o a res w/ just a muffler and mine isnt loud at all, it sounds dam good

 

That is because the turbo helps dampen some of the exhaust sound.

So yes. You are right.

 

Yes it does

I did the "muffler delete" on mine and it sounded like **** so I had to put the muffler back on haha

 

X2

 

my 3" isnt overly loud.. it's a teenie bit louder then my tsudo.. however it's definitely louder then stock lol

 

I bought the whole thing in 3" which might account for a difference--mid-length header into a 3" DP into the 3" catback. I don't mind a loud exhaust (even though that isn't what ZZP is advertising). I've driven cars with much, much louder exhaust than this that were just fine. What I mind is an exhaust with an uncontrolled drone on the highway that is so bad no one wants to ride in my car.

I think what I'm going to try is one of the new Dynomax VT mufflers. I fully expect it will be substantially louder at throttle, but it should help to control the drone levels at cruise. If it works, it's by far the cheapest solution. We'll see.

 

Yeah if you have the LSJ then buying a 3 inch exahaust (catless) is gonna be loud

On the LNF a full 3 inch (catless) isn't loud, it sounds good like I said before

 

Oh, it's catted alright. Still sounds like riding in a diesel dump truck with the muffler off.

 

Get an auger exhaust insert, quiets it down almost to stock unless you're really on it...

Pertronix makes them for ~$13

 

then you have a leak somewhere / almost sounds like your open dp thats how my car sounded when my header/ dp separated/ almost how it sounded when my catback came apart so i was running no muffler

 

mines nice and quiet and its way deeper sounding than most....o yeah **** I has turbo lsj lol

 

the lsj is very very loud to begin with... i have the new zzp setup and it is loud but its what you get when you want a good flowing exhaust

 

See my update at the beginning. Got the car into ZZP today and they took care of installing a new muffler. Car is great so far.

 

Turbo's generally always sounds better than the supercharged on the exhaustportion anyway.