Hey guys. I am about to get myself new exhaust, I guess ill go with something like UUC-C, but the question is where to get a catalytic converter pipe? Ill have to replace mine couse person who installed mine a long time ago replaced original 2 cats (out of 4) with some crappy aftermarket big one

. The way I drive I burned out everything inside and nowi t makes annoing sound when I am on low rpm. Any sugestions on this one ?
Thank you in advance.