Perhaps this has been addressed, but I made a few interesting observations. I recently purchased a stock NISMO take off to "enhance" my non-NISMO 370. I had hoped for a slight performance increase (yes, I did realize a slight improvement) and better sound. The performance increase manifested itself in a greater willingness to rev quicker, but I must admit, it could have been wishfull thinking! The sound was deeper, though not by a lot. For grins, I then installed the stock muffler onto the NISMO pipes. First, I noticed that the stock muffler was significantly lighter in weight. The exhaust "note" was more aggressive than the NISMO. Still not what I had hoped for, but a darn sight better than stock and better than with the NISMO muffler.
Can anyone help me understand this?
