Hi guys. im new to the g37 scene, having owned my 09 g37xS for about 2-3 months and the first month of ownership, i have installed an ark grip exhaust on it. i did it myself with the help of my dad, and when we first got it on it was really loud and i liked it a whole lot. but then, we found an exhaust leak and took it to a muffler shop to get it professionally installed, from that point on the exhaust is really quiet but there are times when its really loud... whys that? like i dont understand how sometimes it is really loud (which i like) and sometimes it is near stock sound.

on the other hand, if i put on some hfcs/test pipes will that fix the problem??
please and thank you!

 

Test pipes will definetely solve that problem if you like loudness.

Hfc are quieter than test pipes.

 

If you really want it to be louder go HFC or TP.

 

Did some research, and im definitely going to get the GTM Resonated Test pipes....
but i'm still wondering if anyone can tell me why the exhaust is sometimes so loud in the cabin and sometimes its near quiet.

 

Google: helmholtz resonator