catalytic converter

[armadillon]

er..it's not always entirely illegal. Like in most counties in Texas we don't have emissions testing. At all. So you can run pipes with only a muffler. So you wouldn't get mega-fined.

The bottom line is: Don't bother hollowing out your cats because theres no performance increase and you can make money off the stuff inside it


EDIT: DAMN! I got ninja'd above!

 

[lil_Blue_Ford]

Hey guys... Remember it isn't illegal for all of us to remove or hollow out the cat. I was looking at that piece of rust called an exhaust pipe on mine a couple of months back and remember thinking that I have about 15 feet of roughly 2 inch stainless left over from a bannister project in an office building that could be bent into a sweet looking stainless tailpipe. Then I hit the search and started reading about the how the truck would react without the cat. Well needless to say after reading a few posts I still have 15 feet of unbent SS pipe and a piece of rust from the muffler back.

Now at the risk of sounding stupid... I just looked on ebay at stainless cats. Right off my Y pipe is a cylindrical unit that I think is the muffler but it looks like some of the stainless cats. What I was presuming was the cat is a more rectangular looking thing just before the axle bend in the tail pipe. HMMMM... which is which? Maybe stainless exhaust will happen if I have them backwards. You can tell I am an old timer because cats were not cylindrical and for the last several years I have had diesels which don't use them.

It is not illegal for everyone, you are correct. But in terms of the majority of the members of this board, it is illegal. Plus since the site originates from the ol USA and it's illegal here, that's the stance of the board.

Cats come in all shapes and sizes, but they are always located BEFORE the muffler, thus the cat should be the round lump right after the Y pipe. You may or may not find that you need a muffler. My F-150 had the pipe fall off right after the muffler not long after I got it. I threw a turndown on it and called it a day. Then it broke right after the cat. I rode around like that for awhile, but I wasn't happy with the sound or the performance, so it got a high-flow muffler and a short pipe kicked out in front of the back tire. Much better now.

 

[lil_Blue_Ford]

er..it's not always entirely illegal. Like in most counties in Texas we don't have emissions testing. At all. So you can run pipes with only a muffler. So you wouldn't get mega-fined.

The bottom line is: Don't bother hollowing out your cats because theres no performance increase and you can make money off the stuff inside it

Actually, federal law states that if your vehicle came with a cat, it's supposed to have one on it. Even if your locality or state doesn't do emissions testing. Where I live there is no emissions testing, but if you don't have a cat on your vehicle, it'll fail an inspection unless it was a vehicle made before cats.

 

[adsm08]

While on the subject of catylitic converters, I got a question. How do you tell if you have a bad one?

Do they usualy have a service life? I'm approaching 200K my 99. This was my first vehicle with converters so I haven't really delt with them in the past.

They are supposed to last the life of the vehicle. Symptoms of a bad one are low power, poor fuel economy, and in some extreme cases the cats glowing cherry red and red-hot pieces of debris blowing out the tail-pipe when you floor it.

Also, if you have OBDII you can compare the front and rear oxygen sensor signals on a scanner. The rear should be flat lined, if it switches along with the up-stream sensors after the vehicle gets warmed up, the cats are not doing their job.

 

[PanamaExpat]

It is not illegal for everyone, you are correct. But in terms of the majority of the members of this board, it is illegal. Plus since the site originates from the ol USA and it's illegal here, that's the stance of the board.

Cats come in all shapes and sizes, but they are always located BEFORE the muffler, thus the cat should be the round lump right after the Y pipe. You may or may not find that you need a muffler. My F-150 had the pipe fall off right after the muffler not long after I got it. I threw a turndown on it and called it a day. Then it broke right after the cat. I rode around like that for awhile, but I wasn't happy with the sound or the performance, so it got a high-flow muffler and a short pipe kicked out in front of the back tire. Much better now.

Thanks for the response: I wasn't arguing about the legality of cats and do understand the position of the board. But... You have given me the info that I was mistaking the cat for a replacement muffler. Proves we old dogs may be great at distributors and carbs but get us into the newer rides and all the fun breaks loose. I might have considered running a new tailpipe from what I now know is the cat all the way out the back. But I don't want to risk having my V6 sounding like an angry mosquito so I would have to put in a nice stainless muffler also.

 

[Snoranger]

Actually, federal law states that if your vehicle came with a cat, it's supposed to have one on it. Even if your locality or state doesn't do emissions testing. Where I live there is no emissions testing, but if you don't have a cat on your vehicle, it'll fail an inspection unless it was a vehicle made before cats.

Its technically illegal (in every state, as per federal laws) to tamper with a cat. Tampering includes:
Removing
Changing the location
Modifying
Bypassing
It even includes replacing a functioning cat.

 

[adsm08]

It even includes replacing a functioning cat.

I did that. I was updating my 87's emissions system to match the 88-92 2.9L because parts are more readily available for that style and I'm running an 88 computer anyway. The front flange changed in 88 so you couldn't put an EGR cat in a non-EGR system. I had to swap out the converter.

 

[Andy D]

My 94 came to me without a cat. I had a decent cat , from my 88 Grand Wag. I grafted it into the hacked up Y pipe, then re-used the bodged pipe, and added a new Walker muffler .

 

[CreepyCrawler]

regardless if its illegal or not where im located i didnt end up leaving it off or rodding it out. i figured id eliminate the most pita cause it could be. fortunately its not in the exhaust or fuel system( being as all that was replaced shortly after i bought it), but i do reckon its time to tune up the wires plugs and take advantage of of putting in a new ignition. thanks for clearing all that up though

 

[JoshT]

They are supposed to last the life of the vehicle. Symptoms of a bad one are low power, poor fuel economy, and in some extreme cases the cats glowing cherry red and red-hot pieces of debris blowing out the tail-pipe when you floor it.

Also, if you have OBDII you can compare the front and rear oxygen sensor signals on a scanner. The rear should be flat lined, if it switches along with the up-stream sensors after the vehicle gets warmed up, the cats are not doing their job.

Sounds like I might need to find a way to check those signals then. It'll have to wait at least until I'm off overtime though.

 

['91 ranger xlt]

Yea.... it'll be louder... and when the feds fine you into the next century, you woln't be missed.

well in montana everyone does what they want lol, and everyone here has loud exhaust and the cops don't care.