I recently swapped in a set of res tp to my existing setup that included headers and a nismo system and it was LOUD and super stinky (I'll run another thread on why this setup and results). I ran things like this for a week while I waited for the XYZ to come in w/resonator. Now installed its almost too quiet for me. Besides clearing up some fumes what has experience found with the XYZ cat? I have zero rasp now for sure and to be honest it wasn't bad with just the res tp. Does the cat module make things even quieter than the res module? I have noticed it seems to be a bit choked on the low side since the addition of the XYZ and the res which is a work of art, no doubt. Is there a burn in period for the res mod itself? I wish I had the straight pipe mod to test as well see how that effects that low end. Thoughts of dumping a little diesel down that res module and sparking it up to burn off some packing comes to mind. Just thoughts in my head knowing that in the end fumes may trump all decisions.

 

it will quite it down, you went from an open tube having no restriction to the XYZ with the cat in it, the cat has a honeycomb pattern that the exhaust passes through. depending on the amount of cells in the cat is going to vary the loudness some

 

Really is that what a cat is? Looking for back to back comparisons to be exact.

 

http://en.wikipedia.org/wiki/Catalytic_converter

 

http://en.wikipedia.org/wiki/Sarcasm