Thanks to Stealth for this finding!!! You rock dude

All that are interested please see the gutting your cat thread in this section. Stealth told us his finding and I am passing it on. The thread has this info and I will tell you how I got it done in a shorter period of time.
That 9" of "extra cat material" can be removed from the rear by just obtaining a 5ft section of 1/4 inch threaded rod from Home Depo/Lowes and ramming it repeatively into it. This size rod is thin enough to go around the bends of the assembly but strong enough to break up the ceramic.. Be sure to mark the rod to the dept you need(you dont want to go into the front section of the cat) and dont go past it. The rod can be bent on the end to increase the area it cleans as you go. Wear a mask when you are doing this as when you are shaking out the pipe to clear it --it can get a little dusty and I wouldnt think you want to beathe that stuff into your lungs.
Damn good find.
olddragger

 

breaking the law, you evildoer!!!!

beers

 

I used to do this for my Hondas when I was like 16. I'd use a grinder, crow bar and a large hammer....and just smash away. Just make sure you guys wear eye protection and some sort of HEPA filtration mask. If you inhale the ceramic dust...it can get ugly.

Oh yeah, and make sure you don't let any tree-huggers see you doing this. I got "reported" once when I was younger. I had to explain to the local fuzz that it was a science experiment...

OD,
But wouldn't it be better just to have someone weld some flanges on a "test" pipe? That way, if you ever need to smog again you could just throw the CAT back on?

 

but you see--it passes emissions this way also. That is one of the good things about this.
ditto on dont breath this stuff in.
I can tell a little differance in the car
Sounds a little deeper (i have the RB catback).
olddragger

 

+1 on testpipe

 

how would it still pass emissions if you knock out all the catalytic elements?

 

Yeah - this def wont pass emissions.

Why not just buy a $200 cat delete pipe, and put your OEM one back in for emission testing. Switching a cat pipe only takes about 30 min.

 

and will save you money on the long run as well from having to pay off smog people or what not.

 

You are missing the point, the catalyst is STILL in place, works 100%, and will pass any emissions check - even a visual or a disassembly by the dealer.

O.D. ain't nobody's fool......

S

 

The difference is Georgia doesn't have a sniff test, California does.

 

BigOLundh and toxin440, with this mod you aren't removing *all* the cat material, the cat has two "walls" (excuse my english) one 7'' and the other 3'', you are just removing the 7'' one so the 3'' still works (it's there for safety when the 7'' is consumed) or something like that and you PASS emissions.

I'm trying a resonated midpipe shortly, if it's get too loud for my taste I'm doing this.

 

exactly correct --you still have cat material left. you are only removing the part that is past the last o2 sensor. So it should pass a sniff test.
This cleans up a lot of really unnecessary restriction in the oem cat. Therefore making it like a high performance one if not just like one.
olddragger

 

so... we all know how the 8 is mods...
but, im in FL. im not worries about getting tested for emmissions... how many hp do you think can be freed up this way. and how about with removing all of the material? (7" and 3")

 

If you remove all the material you have a midpipe, it'll trigger CELs, and won't pass emissions (and probable give more power too) but to have it that way it's better a normal midpipe because of the chamber shape.

 

Has anyone else tried this?

 

I'm wondering the same thing as well..

 

To clear up some confusion here, this is the text of the original post O.D. is referring to -

I solved this problem for myself two years ago.

While getting my car fitted for a wide-band O2 sensor, I noticed that the secondary sensor sits in a space between blocks of catalyst. A little probing with a dental mirror showed that the cat is made of a front "bed" about three inches deep, then the space, then a rear bed about nine inches deep.

The principle is that the cat works from front to back, as the coating wears out, the reaction takes place deeper inside, until the sensor sees no difference in the gas between the first and second readings, at which time it lights the CEL for "failed cat". The only reason to have the second bed is so the car will still be OK to drive, even if you ignore the light for years. When only the first quarter of the cat is used up, the sensor will be on.

So my answer was to remove the second catalyst bed, cutting 3/4 of the material out, while maintaining full functionality, 100% legality, pass any emissions check - including a visual. Even a dealer/mechanic could not detect any problem, unless he had x-ray eyes!

Car sounds better, runs better, throws 'large' flames when prompted, and has been working like that since October 2004.

The actual removal was not as easy as it sounds - the best way would be to attack the material from its outlet instead of inlet, but that is thru the resonator and around two good bends. That way proved impossible. I succeeded by chipping away thru the sensor hole. That is also much harder than it sounds, took three days - the hole is roughly the same size as a sparkplug hole!

If I were to do it again, I would cut the assembly in two at the back of the cat body, allowing easy removal, then get my friendly stainless steel welder buddy to put it back together.


S

 

thanks Stealth--I should have done that on starting the thread--rather than saying "refer too".
I can verify my seat of the pants"runs better" and it does seem to pull stronger in the top end. again this is seat of the pants and an old butt setting in them.
olddragger.

 

Any pictures in progress?

 

..yet.

Every month a new law goes into effect somewhere concerning emissions.

Clean areas are getting dirtier air everyday, and with it comes the EPA clean air rules.


Smog checks..mod like you have em to protect your investment for later.

Its not like theres any real power in dicking with emissions stuff.

 

So, you reeeeally don't have a clue do you. Look I'm all for clean air, but if you would care to read about how our cat works you would find that the "cleaning" takes place in the first catalyst wall/barrier. As the exhaust has already been "cleaned", the second barrier does nothing more than hamper airflow and is only there to pick up cleaning duty after the first one fails and triggers a CEL. So, if the first one failed you would replace the cat to get rid of the CEL even though the second catalyst was doing the same job. It is redundant, unnecessary, and reduces high end power. Freeing up a little more power theoretically would result in better gas mileage. Something we would all like.

Enthusiasts are looking to improve their cars tuning for more power. More power is gained by better tuning that more efficiently burns fuel which lowers emissions. Tuners are good for the environment

 

Wow this sounds like a great idea. Anyone up for making a DIY?

 

I refuse to have a country that produces 50% of its electric energy by burning COAL tell me about emissions... Here's a choice quote: "America's traditional coal-powered plants pump 2.3 billion tons of carbon dioxide into the air each year — twice the amount cars produce."

Emissions laws should govern production, mass-market cars, but there's no reason to dump on the automotive enthusiasts... How about this: all cars come with all the regular emission stuff, but allow people to remove it if they wish. I bet that 99% of people still would not do it, because it smells like ****...

< / rant >

That put aside, if this "mod" doesn't affect the emmissions performance, then I might think about it... Sounds like quite a hassle though... Here's a great idea - someone should take a supercat, one of these, and dyno to see the difference :-D

(yes, I am just trying to get someone to do the work for me...)

 

Pictures please.

 

sosonic the area that gets pulled is not able to be seen without using a fiber optic camera.

Anyone have one?