Hi, I'm new to this and not sure if it's been asked b4 but I have a G35 04 coupe with non-resonated test pipes, ISR y pipe, and muffler delete. the y pipe was recently added and idk if it's the famous rasp or not but every time I accelerate I hear this rattling noise that annoys me. like when I had the stock y-pipe, it sounded better and had no rattling/rasp. So my question is would be getting proper exhaust help, or should is there anything else I can do? thank you for your time.

 

Probably something literally rattling around under the car, verify it's not touching anywhere and that all the bolts are tight.