i just got a stock cat put back on my car today. i was so tired of how loud my exhaust was (greedy evo). my old cat was gutted out. well, i dont know if its just mental or what but it seems like my car runs just a bit slower. it goes through RPM's at a slower rate. Should i have just keep the gutted cat?? my exhaust sounds real clean now though.

 

as long as you are happy

 

happy with the sound now. but dont know about the performance......

 

yea i think you loose MINIMAL hp with a cat
i mean were talking like 5 i think.