Has anyone deleted their cat?

The front catalytic converter has been going out in my truck progressively over the past 6 months, the innards are all broken up inside and it rattles like crazy, sounds like there's marbles bouncing around in there and I am at a wits end listening to it. I don't live in an emissions state so I am just going to delete both the cats and call it a day. Has anyone done this and what does it take to do? I want to be able to take them out and not throw codes or make it not run right. Mine is a 2004 so if you have one close to this year let me know what you did. I looked into replacing the cat, but Toyota stealership want's $1200 for a new cat and I refuse to pay that much for one.

 

My sister would get so mad if I deleted the cat. She's had that thing since it was a kitten. Probably about ten years old now.

 

Replace it then, dont be a doofus and run a gutted cat..

 

^^ cruelty to animals

 

I paid $330 for a new 50 state cat.. 49 state ones are like $150.. your argument is invalid.

No one buys them from the dealer.. HA

 

OP, sorry you bothered to ask a good question but only got douchebaggery in response.

I too am about to delete my cats. The reason is that my exhaust system is rusted out and I don't have much money to throw at my truck. I plan on running an O2 sim to balance everything out. Also, I am downsizing my mandrel to avoid losing low end torque. Will try to keep you posted on the results.

All the best.

 

So breaking emissions law and making your truck run like shit without an O2 sensor trick that costs almost as much as a new cat concert or is not douchey?

Clearly all of us people that what to keep the trick running correctly must be crazy...

Carry on.

 

O2 sim is $10 bud

I'm not doing this to break laws or make my truck run shitty, on the contrary: my exhaust has nearly 200,000 miles on it and has spent its life in the salt-belt so it's very much disintegrated. When I take it to pieces I'm hoping that one or both of my cats is still in good shape, but, if they are not, I will not be able to afford new one(s) so will have to find an alternative measure. Will be reducing mandrel diameter to avoid losing low end torque.

Also Micah, the douchebaggery comment was not directed at you, we posted about the same time that's all. The comments before yours just looked like daft jokes in response to a serious question which seems to be all I see on TW these days (other than people re-hashing the same daft questions and arguments that any muppet could find with a simple search) no hard feelins buddy

 

i have 202k miles too and have replaced everything, the headers, both cats and muffler along with all piping.

 

lol second forum ive seen this guy and he beats me to what i want to say

 

When i was 19 and had a 94 S-10 I gutted the cat thinking it would be cool and it sucked so hard I bought a new one the next day.
So all of my posts are speaking from experience.

 

what other forum are we both on?

 

that one about the guy asking about what that random aftermarket switch does. when i read his question, my first thought was a trunk monkey and you beat me to it

 

LOL yup haha

 

Yeah I am lucky in that I don't have to worry about smog law. Although, I will point out that at this point in the US it really comes down to what city you live in.. If I lived in Cleveland, for example, I would have to smog. Fortunately I live in Columbus. Also, I have no desire to run cat-less, that is just an unfortunate short-term solution until I get some money in case I found both my cats to be fried. I need the truck for work and I need to work to afford new exhaust components.. blahblahblah.. it's a temporary solution until I can get my baby what she really needs

 

ok, i'll play

your exhaust system needs the back pressure supplied by the cat for it to perform correctly.

if you are going to hollow out the cat, then you need to install a restrictor plate in the flange to simulate the back pressure you lose by knocking out the cat. so to be clear, yes you can remove the cat but, no you cant and shouldn't remove the restriction caused by the cat.

so, to recap, yes you "can" remove the cat AND keep your performance, but "only" if you add the exhaust restriction back that the cat provided. that said, knowing how to set just the right restriction for best performance would be challenging and is not very practical to expect to be able to do yourself but by blindly guessing at different hole sizes could let you stumble upon something close enough to the right choice to be satisfied.

as to the subject of cost of o2 simulators and the logic of the choice, I will leave that to others to address

 

replaced cat on my truck with a glasspack muffler. The one cat (some have 2) on this truck is by no means a restriction with these motors. I would like to see some sort of results that show that the truck will "run like shit" with just the cat removed from stock system.

 

I have an 02 tacoma with a 2.7l five speed. Mine had dual cats and i live in northern wisconsin. Rust took care of my exhaust. I went with the o2 simulator from trd. I tore my header off and welded up the small rust holes in it. welded my first cat solid to the header. Gaskets are notorious for leaking in between the header and first cat. Then i punched out what was left of the cat material inside it basically turning it into a straight pipe. cut off my second cat and sold it to a local junkyard and used the money to by a new muffler. Didn't ask for anything special. just had to cut down noise. My exhaust now runs out the passenger side of my truck and is maybe four feet long from the bottom of my new header. My upstream o2 sensor is in the original location on that first gutted cat. My second downstream sensor is two inches from the end of my exhaust right after my new muffler. Never had a code come up after i did this and my truck is snappier. No idea what other people have done to fuck up their performance but I live in a state with no emission checks and have never had any bad smell. hundred dollars and sell your cat to cover the new exhaust work.

 

I don't live in an emissions state either was why I was asking. Cats are not necessary either, cars were made for years without them and ran just fine.

Besides that, I run zddp additives in my motor oil, zinc and phosphorus kills cats so it would be pointless for me to spend the money on another just to have it go bad again in a year.

 

i do know a bit about scavenging. From what i know its better to have the cat replaced alltogether because the empty gutted cat allowing the exhaust gases to expand can do some funny things. I would like to see dyno results or something between a cat and test pipe. Most changes with exhausts and intakes with these trucks dont do much of anything as far as what ive seen/heard.