Ok guys, my truck is straight piped, sounds mean as hell and is louder than most trucks in my area. Recently though some guy bought a 05 ford and did something to it to make it almost twice as loud as my truck and I'm not gonna take that sittin down. I still have the stock exhaust manifolds and catalytic converter. I just saw a video of someone else on this forum who just installed long tubes....sounds so sexy... and i've decided to have those installed but my question today is, if i remove the cat, am i gonna have any problems? I know there's a sensor on it and i'm afraid if i remove it then i'm gonna have issues.

 

the one thats on the cat is the upstream and its the one that keeps your air/fuel ratio correct. if you're gonna straight pipe it then you could get a spark plug non fouler and cut off most of the threads, then drill a hole in the pipe you're gonna put in place of the cat and weld the no fouler in the hole. then you'll have threads for the o2 sensor. but remember, here in nc the inspection guru's look to see if you have a cat so if you're gonna go that route you may want to cut your cat in half and hollow it out then weld the shell onto the replacement pipe so it'll look like you have one.

 

Most people don't have any problems with removing the cat. Sometimes few will get a MIL or CEL light, but that is under load.
I punched the guts out of mine about 5 months ago, and have not gotten a MIL yet.










Oh, wow 2,000 posts.... all worthless of course

 

dont have to pass any sort of emmissions test here in jones county, in fact, the place i have gone to the past ten years havent ever looked under the truck at an inspection so i think i'm safe there

 

Leave the front O2 sensor in there, as Sheriff420 described or another way. The truck won't run right without something telling it how to adjust the fuel/air ratio properly.

 

alright so let me see if i'm following you guys. All i'm doing with that spark fouler thing is relocating the original o2 sensor to the new piece of pipe that i'm gonna weld in right??

 

A non fouler is basically a resistor that tricks the PCM into thinking that there is a sensor there.

 

i just hollowed out my cat a week ago left both sensors in and i dont have a cel yet. but i think it sounds like crap, because i can hear the exhaust in the cat before it even gets to my muffler
sorry to thread jack

 

This is a non fouler.

 

or http://www.thefastman.com/02Simms.asp