Originally Posted by Silly Rabbit

I've read where other Borla owners removed high flow cats because it didn't sound good. Joe at Zspeed said he had a customer with Borla that had him replace the high flow cats because it didn't sound good. He suggested the ART pipes.

I see ARK has a resonated high flow cat, but I have AT7. The other resonated cat I've seen is from Fast Intentions. How much difference in the FI RHFC and the FI RTP? Are there others? What about the ART pipe's claim to have no rasp or drone?