is there a noticable noise difference b/w running a high flow cat on your turbo exhaust system and running just a straight through design??

i'm considering buying a high flow to help lessen the noise associated with the exhaust.. currently i'm running full 3" piping w/ a 18" resonator and typical 3" muffler.. on the hwy, the exhaust is still audible and sometimes gets annoying..
it makes me want to try and get a system that is alot quieter... how do those porche 911's do it??

i'm open for suggestions..

 

i have a 2.5" Carsound cat on my N/A setup now and it's quiet and clean

i also have a 3" Carsound cat waiting for my turbo setup when that finally gets installed. i like cats cause they are cleaner and more quiet than a testpipe or the like.

 

Get a resonated test-pipe to lessen the noise. See this similar post:

http://forums.clubsi.com/showflat.ph...sb=5&o=0&fpart=