ok so i have a 91 camaro with the dual cat setup. my plan was to but out the old cat and weld a 3bolt flanges onto either side. i would do the same on the existing pipes on either side. couldnt i take a piece of stock pipe and weld flanges to it and put it into where the cats use to be? then when emissions come around unbolt the pipe and bolt the cats back in. anyone ever done this. maybe someone has some pictures or advice on doing this?

 

I had the same idea too.... you should read this thread through before you continue!

https://www.thirdgen.org/forums/exha...ml#post4294963

Good Luck!

 

you'll get a lot of crap on here for not having a cat...

i just dropped the cat and bashed out the catalyst with a crowbar and a hammer and put it back in. so now it looks like i have a cat when i really don't. the nice part is that now it acts as a resonator and the exhaust sounds way better. and the cops can't bust you for not having a cat bc they can only do a visual inspection. so as long as it looks like you have one, you're good.

HOWEVER- mine is an 83, so its 26 yrs old and is emissions exempt. you may not pass the emissions test if you are still required to have one. i'd only recommend this on an emissions exempt car.

 

thats what i did i took mine out cause i run cam 2 112 at the track so i took the cat out

 

Pretty much what you're making is a test pipe.Guys sometimes make a pipe like that to run at the track. I'd check you're local laws they're different everywhere.

 

oh!

 

But I still don't know why so many on here, get all bent when someone asks "How to." Buttom line here, its YOUR car, and YOUR the one taking a risk braking the law, not me or them!

 

We don't give people "crap" for not having a cat, we just don't see the point in doing it. Not worth the fine for tampering.

It's just that, with a nice free-flowing cat, the meager amount of hp they'd rob is SOOOO minimal, it's not worth risking the ticket to do.

Get a Hi-Flow cat & call it done.

 

with Stephen.....I posted the same question a couple of weeks ago. After reading everyone's advice/opinion, I have dicided to with a High flow cat when I'm ready for the change!

 

Exempt only means no test required. It does not mean that you can LEGALLY take it off.

 

Definately alot cheaper for those on a budget to remove it and fit a pipe in than to drop $100 plus on a high flow cat. Playing devils advocate though, getting caught without one could cost you heavily and make that money a high flow would have cost seem like chump change.

 

And being cheap was my reason at first too.

 

yeah thats my problem too. i dont have the money to go out and buy two free-flow cats. so i was thinking about a test pipe just to test it out and if for some reason i dont like it...i put the cats back in no problem

 

I had my cat off for about 4-5 years now along with the A.I.R system and when inspection time come i unbolt the test pipe and put it back on. pass and and it's off again.

and in all these years i never got a ticket, but you will get high of the unburnt gas and fumes lol

 

i never said i could legally take it off. i said that i wouldn't recommend it for a non-exempt car bc it prob wouldn't pass the sniffer test. i hollowed out mine not bc of the hp, i did it for the sound, and it sounds a LOT better than it did. and i had a Dynomax hi-flow cat. like i said, they can't give me a fine bc it LOOKS like i have a cat and they can only do an exterior visual inspection- they CAN'T take it off the car and check. and with my emissions exemption, there's no way anyone would know i have a hollow cat unless i told them.

 

Will hollowing the cat throw any engine codes?

 

not that i know of. i've never had any issues. my car is carb, so idk about the TBI or TPI cars.

 

you want a cheap very high flow cat check this out. http://cgi.ebay.com/ebaymotors/3-0-N...#ht_2348wt_928

it is really a test pipe but looks real!

 

That was exactally what I was planning on making....BACK ON THE FENCE!!! But I wouldn't destroy mine, I'd just keep it as a spare or back-up. I would get one the wreckers and hack that one up.

 

Nobody gets tickets or fines for not having a converter. Sure, they could, but it just doesnt happen in the real word. People trying to sell that angle are full of it.

Yeah, lets waste $100 bucks a pop on new cats that will probably last 2 years and do it all again then. Right. Great advice

Keep your original converter, get the test pipe, use both as needed.

 

Speaking of bad advice...If anyone has new cats and they last two years, it's not an issue with the cats.

Its going to be a tuning issue for sure.

 

So you, as long as you've been around this place, havent read about cats just falling apart? Specifically catco?

So no, its not "going to be a tuning issue for sure". There are plenty of cases of a substandard part, and honestly, from a pass the sniffer point of view, the originals are the best.

 

No I haven't. I had my Catco on much longer than two years. No to mention, if your strictly speaking about Catco, there are other brands out there. So no, there is no reason to say they're going to fail in 2 years if your just talking about one brand.

 

Then I'd say you were lucky. There are many people that have had aftermarket converters physically fail. As in the stuffing comes apart and blows out the back side, jams up in the muffler, etc.

So like I said, it NOT going to be a tuning issue for sure as you stated. Many others have had them fail for other reasons too. Some in much less time then 2 years, and that includes other brands too.

 

3.5 yrs on my Magnaflow cat & no sign of it breaking down, no rattling, no apparent lack of power, no obvious clogging.

Wnat happened to the "2 yrs = cat death"?

 

I've got the TPI setup. Has anyone with TPI seen codes after hollowing their cats or know if it would throw codes?

 

Did I say every single one of them would break down before 2 years?

EDIT- I'll be nice, I know Stephen is sensitive.

 

Nice editing, but you said aftermarkets fail after 2 years, only the OEM ones last longer. And here is what he really said & edited out....

"Did I say every single one of them would break down before 2 years? Grown up's are speaking, its not nice to interrupt."

I'm not "sensitive"....I just don't take crap from dumba$$eS like YOU!

 

TPI no.... I got a friend with a 94 Caramo LS1, has a hollowed-out Cat, No codes....

 

Feel free to read what was actually written. Until you can accomplish that this is a moot point.

 

I am so glad that where I live we don't have smog checks or test. My stuff is gone and duels in.

 

In my opinion, the chances of a cat failing early because of a tuning issue such as running rich is much greater than it failing early just because it's defective.

 

I think thats a much better assessment then what you originally stated.

 

i hate how these types of questions start such a heated debate...

 

before this gets locked......i think we got more important things to talk about than this **** about cats and emmissions. honestly people, don't give a flying **** about somebody a 1000 miles away from u.

 

I believe that also goes for saying that they all are just going to fail in 2 years also and not worth it.

Ok. Closing this one guys.