Can someone tell me why my dual catalytic converters are being burned out? This is my second pair of cat for my car. First, replaced the stock with universal set (dynomax) they lasted for nine months so I went with a complete catco dual set-up, now it wasted. I spent close to $500 for cats in the past 19 months. I have a few bolt-on mods, with headers and I'm running full emissions.WTF

I'd be pissed too.

Are you throwing any codes? It's probably a lean or rich issue that you're having..

I know this isnt gonna help any, but id stop buying cats. There is definetly something wrong with what your engine is putting out if its eating through cats like that.

heh, buy another dual cat setup, and only put it on when you need that emissions sticker.

I hear the chunks ratteling in one of the cats, I took off the y-pipe and alittle of the fiber matting came out, I'm going to try to send it back, maybe it will be replaced? no codes are flashing. If all else fail, I'll gut them untill I move to Colorado next year.

Cat's will generally go bad because of a very rich mixture. The unburned fuel collects in the converter and burns in there and overheats it. You probably have some sort of fuel management issue. Do you have an aftermarket fuel pressure regulator, or bigger injectors? Make sure the computer is not giving any codes and is running in closed loop mode. You could gut the cats, but that still doesn't fix the problem of a poorly running engine. By fixing the problem at the source, you will have a better running engine that makes more power, and gets better gas mileage, as well as not destroy converters.