Hollowing out the catalytic converter on VX

[giperbolic]

I did search and this was asked once before, but I couldn't find an answer. What are the negative affects of gutting the internals of catalytic converter on VX except noise, smell, high NOX emissions? Are there any FE, O2 life, engine affects?
Also, how do check if cat is bad? The engine I swapped in my car has been sitting for 11 years, so I figured cat is rusted and clogged, but I haven't opened it up to look. Engine is running.
Thank you.

[GasSavers_Erik]

If you punch out the cat the exhaust will be much more "stinky" (a little unburned fuel will be present) also more carbon monoxide will be released out the tailpipe (not good- especially if you carry many long loads and have to drive with the back hatch open).

To test to see if the cat is plugged, watch a vacuum gauge as you rev the engine to 3K or so. Let the throttle snap closed, the vacuum will increase slowly if the cat is clogged. If everything is OK, the vacuum will build fast.

[theclencher]

Don't gut it unless you are sure it's destroyed anyway.

[markweatherill]

Remember that stuff inside is quite a health hazard, seriously.
And it's possible to hurt FE and performance by gutting a cat in good condition due to gas flow changes (it becomes more turbulent in the empty canister)

[R.I.D.E.]

$2500 fine for owner tampering. That's Federal law. Your state may vary.

Prove its bad first at least. You can have it rebuilt for a coupe hundred dollars or get a good used one.

regards
gary

[pat63]

just want to share this link http://www.ehow.com/how_5135432_tell...r-clogged.html on how to solve the issue if your catalytic converter is clogged..

[Jay2TheRescue]

I don't know why this hasn't been mentioned before, but we really should not be supporting violating federal emissions laws here... I recommend if your cat is plugged, replace it with a new one. You can probably get an aftermarket cat for under $100.

-Jay

Originally Posted by pat63

just want to share this link http://www.ehow.com/how_5135432_tell...r-clogged.html on how to solve the issue if your catalytic converter is clogged..

[jmaze]

i gutted mine out in 95' for better performance, so i thought, and on the freeway i felt my vx backfiring from time to time.

[GasSavers_JoeBob]

Originally Posted by Jay2TheRescue

I don't know why this hasn't been mentioned before, but we really should not be supporting violating federal emissions laws here... I recommend if your cat is plugged, replace it with a new one. You can probably get an aftermarket cat for under $100.

-Jay

I tried removing the cat on my Chevette some years ago when I was trying to track down some problems with FE. Over several tanks, noticed no difference in performance or FE. Put it back on. Conclusion: A properly functioning cat has no deleterious effects on performance or FE. Better to use it, be in legal compliance, and pollute less.

[willix]

most all cars pass emmissions tests without a cat since the late eighties. Big brother requires use to have a cat anyways and it will effectively clean-up the exhaust further.

The draw back to hollowing out the cat is if its found that you need one it will cost you dearly to replace.

It will change the dynamics of a factory tuned exhaust that may hurt economy

There is a remote possibility you could face a fine up to $10,000.00 & jail time.