Magnaflow 2.5, took out my cat!!!

[JCamaro3800]

Hey ok heres me situation, a few days ago my car got real sluggish and had virtually no power and my SES began blinking. I took it up to my local shop and they diagnosed that a cylinder was misfiring. So I got new spark plug wires like they told me to but that still didnt do anything. I took it back again and they said my cat is clogged probobally because raw fuel was getting in it and reacting with the chemicals. Ok so me an my friend who has a 96 LT1 have been going at my entire exhaust for 2 days with a saw and finally got the majority of it off. I have a Magnaflow 2.5" Catback in the mail and that will be coming probobally tomorrow. My first question is what kind of catalytic converter should I get? I really love the way my car sounds with open headers but I will have to get a cat. Also, I have a K&N Aircharger and I know this is a longshot but do you think that raw fuel could have been getting into the cat because the K&N was getting so much more air to the engine? I know this is alot but any help would be appreciated. Thanks!!!

[99v6cam]

More fuel means less air, in other words, it wasn't getting enough air. The raw fuel was probably caused by the misfire though (no spark = no combustion which = fuel in exhaust)

[Yaba3800]

i dont think that one misfire is enough to make your car sluggish and send off a ses light. that sounds ridiculous. go to a different shop and have them run a obd2 diagnostics computer tester and it will give them a trouble code. this will point nearly directly at your problem. just got done doing spark plugs, air and fuel filters on my car...ran tons better..