Issue with aftermarket exhaust!!

[fenderpicks]

Well as some of u know i installed the Greddy Ti C racing exhaust on my coupe like 2 months ago, and ever since they day it was installed everytime i step on the gas i can feel the vibration and i can hear like the windows are like moving/shaking whatever u describe it. And that only happens when the window is all the way up, if its down i wont hear the noise anymore...

So basically anytime i step on the gas the entire car is vibrating

My question is, is it that i didnt tighten the bolts hard enough? Or is just the exhaust's problem?
Also the silencer is off, all this time.

[Hussain]

idk about the greddy exhaust or the 2.5 but with my exhaust I used to be able to make coins in my car jump because the vibrations were so bad I got a resonator installed and the car sounds almost exactly the same BUT it doesnt have the bad vibrations anymore.... now my car is decent, but far from quiet inside

[BlackMetal]

the vibration or rattle is from resonance. Even the nismo exhaust did it just a little bit at certain rpm`s... not the window`s tho, more like the headliner near the sunroof for this one...

[LongBeachCoupe]

Hmm... Hanukkah harry bringing you some dynomat?

[QR25DE]

Yeah that's what 2 far cans will do... hahahah

Thats why I went with the Greddy Elite exhaust. I KNEW the farts cans are loud and cause vibrations from experience. The elite is super quiet when cruising. Puts out a lovely sound too.. then psshhtt to finish it off lol.