when i bought the scion tc used it already comes with TRD muffler and TRD cold air intake, I took out the CAI recently and found out it sounds the same, so what is the use for cold air intake?? will it have any sound difference?? I plan to install weapon R short ram intake and can anyone tell me will it add more sound on my car?? will the SRI sound differece comparing to TRD CAI..just trying the figure out is it worthy to install it. Thanks!