The thicker gauge steel, the extra resonator, and the larger muffler is what keeps the DBs down on the Greddy unit. It's a great unit, but I personally am running the Helix cat-back (V2) which weighs in at less than 25lbs and is really not that loud as opposed to say a STI running the same cat-back.

Cheers,

Gary
Gruppe-S

 

Here is my previous 05 EVO with mbc, intake, and Gready EVO 2 turboback (no cat).


http://video.google.com/videoplay?do...3525&q=evo+mbc