Catalytic Converter . . .

[huskyfan23]

Hey there, I have a Veteran's Tab on my liscense plate, meaning it's a lifetime tab and doesn't expire, so I don't need to go through emissions. Might as well get somemore HP out of it without worrying about emissions. One of the things I was thinking about is the catalytic converter. I don't want to remove it, because I've heard there's a $5000 fine, just in case. So I'm thinking about hollowing it out. How should I go about doing this? I have a '94 4x4, so does this version have an o2 sensor? If it does I should leave it, shouldn't I, THANKS!!!

 

[Rick]

Just get a hi-flow catalytic converter. You can see right through them, they add power and deepen the sound of the exhaust all while keeping the crap out of the air.

Mine cost $150, can't tell you a brand name though. It was installed at a local muffler shop.

 

[91Exploda]

Yeah you have a 94 with OBDI so you do have an O2 sensor. In 96 everyone went to OBD2 and with that you have a hego sensor before the cats that see whats going into the cat and after the cat you have a "cat monitor" that looks at whats coming out of the cat. If you gut 96 and up cats or take them off you will have a load of trouble. The hego takes a reading every 10th of a sec or so. The "Cat monitor" takes a reading every 45 mins or so. With the OBD2 you get alot of adjustment that the comp does on it's own. Go ahead and dump your cat or gut it. The o2 will be fine. It just takes a temp reading to figure out when to put it in closed or open loop.

 

[Rick]

Originally posted by 91Exploda
Yeah you have a 94 with OBDI so you do have an O2 sensor. /B]

Hmm... that's funny. I have a '93 with 2 O2 sensors one for each side of the motor.

 

[Robb]

Go ahead and dump your cat or gut it.

The environment will love you for this!

Robb

 

[Alec]

Get a high-flow one, don't gut or completely remove the cat.

 

[91Exploda]

Hmm... that's funny. I have a '93 with 2 O2 sensors one for each side of the motor.

Okay, So you have 2 O2's. Let me guess one in the left side of the Y-pipe and one in the right side. If you have one in the Y before the cats and one after the first cat or after the last than I'm sorry you are equiped with OBD2.

 

[Rick]

Both are ahead of the cat.

 

[91Exploda]

morrisey0 are you making fun of my suggestion. Huskyfan23 clearly asked what he could do with his cats because he has a veterans sticker and doesn't have to go through emmissions. I'm sorry but where i'm from we don't have emissions. If you want to be smog legal be my guest

 

[91Exploda]

Both are ahead of cat. Then you have 2 O2's that monitor each side and adjust the fuel trims for each side rather than the 1 O2 for the whole motor.

 

[Rick]

Originally posted by 91Exploda
morrisey0 are you making fun of my suggestion. Huskyfan23 clearly asked what he could do with his cats because he has a veterans sticker and doesn't have to go through emmissions. I'm sorry but where i'm from we don't have emissions. If you want to be smog legal be my guest

Since we all breath the same air it's only right to leave your cat intact wether or not you have emissions testing.

Since you can get the same output with a high flow cat as you do with a gutted cat or bypass and you still have to run the same unleaded fuel that we all do I see no reason to completely eliminate the cat.

 

[Robb]

WOW, you were quicker than me on that one Rick!

Robb

btw: 91Exploda, may I suggest a little more time reading up on the boards. Advising on yanking out cats and debating with the Administrator don't tend to go over well

 

[Rick]

He can debate with me all he wants I will stand firm on my advise about cats though

 

[X-1]

Hey,
Let me jump in with a quick question. On a 93 it looks like I have two cats, is that true, some have said one is a resonator, I don't want to remove, just curious. On another note, I remember back in the early eighties when we all cut the cats for hp, only afterwards California started the testing, had to buy back those cats for big bucks. Also engines are designed to run with a certain amount of back pressure, removing the cat completely will eventually cost you some valves.

 

[Alec]

Exploder 1, you probably have 2 inline cats, then the muffler. Some X's have a resonator (a long cylinder) after the muffler.

These engines do need a certain amount of backpressure, or whatever you want to call the resistance to flow (not technically backpressure) that small pipes create. Dunno about valves, but open it up too much and it could cost low end torque.

 

[rpenner54]

Rick did you get any crap when you wanted to do this? I wanted to do this on our Quest. As its CAT is plugged up. I have a new 02 sensor on the way to fix that problem. However the muffler shop I called said they can only replace the two with two. They said by law they can't do the two into one deal. Anyone know where to find a specific law about this?

 

[Rick]

Our shop had no problem with it. I have been through emissions twice since then with no problems. They use the mirron under the truck to check for the cat and still no problem.

 

[Alec]

Ryan,
Go somewhere else

 

[X-1]

Alec, thanks, that's what I thought, seeing how they are identical.
Ryan, I would agree with Alec, try somewhere else. If I remember right, they cannot remove, but they can replace, and if the replacement meets guide lines then you are okay. But most places will install what you want, you made need to remove on your own, and take it up there and have them install the new one.

 

[91Exploda]

I must say this. If you do remove your cats. Get a colder themastat. Enginers "designed" engines to run hot to make cats work. If you don't get a colder stat you can run your vehicel too lean. Then you can cause some damage. If you don't know how to do it right you shouldn't touch it. And for your referance Huskyfan23 "I am not advsing you to take off your cats" "I am not forcing you to take them off". You are a big boy and can make desicions on your own. I don't want any flak for my 2 cents Okay.