Thread: ZZP Exhaust Drones...Anyone Use Dynamat in Trunk?

So I just installed my ZZP 2.5" catback and catted downpipe. I thought for sure with a cat, resonator and mufflers, I would be ok...but the drone is awful under light throttle. Cruising seems to be ok...haven't driven it far yet, as I'm at work and installed it at work this morning.

Has anyone used Dynamat or Dynapad in their trunk to reduce exhaust drone? I'm getting conflicting info on this. I'm planning to use both if it'll help. The tone is awesome...there's just too much of it...but I don't wanna go back to stock after just buying this thing. Any help is appreciated....

Usually their mufflers from past reviews have sucked; same with the resonator. If you can find a stock replacement or Walker resonator, it'll really help without having to dynomat everything.

Most tend to add the biggest resonator possible.

I did mat the whole trunk, back seat etc etc and while it quieted things down overall (not exhaust related reasoning), .... it'll never quiet down a 3800 exhaust enough to make it worth the cost.

Forgot to mention ignore my profile LOL...its an 06 GXP with an LS4.

Is DoD still active?

That will cause the helicopter drone noise in the cabin on LS4 cars. You could add a 2nd smaller resonator too so cancel out even more of the drone.

Hmm my zzp exhaust doesn't drone. Any of your connections leaking?

I don't think any connections are leaking, as I don't hear any ticking or see anything funky. I just had the dealer I work for install it yesterday...its just loud as hell and makes your ears tingle.

I still have my stock resonator because a tech swiped it before they threw the catback out. Its 2.5", just like the rest of the exhaust. Should I swap the ZZP res with the OEM res? Is it worth the effort? Some people are telling me to put a long Magnaflow muffler in place of the res, but I'm afraid that won't cancel out the frequencies causing the issue...

And no, DoD isn't active.

Maybe use the rubber undercoating on the whole underside?? Cheaper than the dynomat and it will cover the whole under body. or like the others said add a second smaller muffler if it is a concern. http://www.ebay.com/itm/Exhaust-Muff...-/141700920859

I'd buy a vibrant ultra quiet resonator and install it before or after the zzp resonator.

They cost a couple bucks but they work awesome.

The only true way to remove resonance is to identify the frequency it is eminating at and install a Helmholtz Resonator to offset the frequency. Other than that, you can quiet it, the Vibrant Ultra Quiet is great, and you could install 2 in tandem... I haven't done that myself, but they're only 12" long I think... Lol