Catalytic convertets - Are you also bemused ?

Question

Hi Folks,

Is this American notion that a pan of crystals in the exhaust flow will significantly reduce noxios emmissins correct ?

I have my doubts, as when living in the Mid-East, I had the two things cut ond replaced with straight through lenghts of pipe.

(This on a Pontiac Transam, 4.9l turbocharged V8 thing)

I found that with the increased efficiency of the exhaust system, I gained some power, so considerably much lighter on the gas pedal in day-to day use. Result being about a 15% reduction in total fuel useage.

Are "catties" then just a token gesture to reduce car emmisions ?

All thoughts / experiences thankfully received, as I am thinking about having the item removed from my mothers' little Chevorolet.

Bob

Answer 1

This is not only an American notion. The only problem here is that if your car isn't tuned up well, the Catalytic onverter cannot do it's job and can clog up or partially clog up causing a waste of mileage. Platinum has been proven to "catalyze" fuel and reduce emissions and as far as I know is required globally. There are even such things as high performance CC's that flow more exhaust. These items would aid fuel economy as well. Some manufacturers, especially OEM, have been proven to be defectively made and clog up faster than others. When you remove a "cattie" from most cars, the resultant stink of unburned fuel usually is too obnoxious. Instead of removing it, try tunign the engine properly with Platinum plugs and use a tier one fuel that burns efficiently. The higher the efficiency, the better your power and MPG's

Answer 2

As part of the annual motor test, the exhaust emissions are checked against the manufactures specifications. If you remove a cat box the car will fail the test and cannot be allowed on the road.
Having said that, it is possible to remove the cat and replace it with a straight pipe. Before going for the test simply re-install the cat.
With the removal of the cat the car will run much better.
Ja.

Answer 3

Catalytic convertors do reduce emissions of your exhaust. Of the five gases present in exhaust emissions, cats help reduce NOX (oxides of nitrogen), CO (carbon monoxide), and HC (hydrocarbons). The convertors contain a catalyst, which by definintion is a substance that starts a chemical reaction without becoming a part of that reaction. The cat you removed from your Pontiac may have been somwhat clogged, or poorly built, because the way that catalytic convertors used on cars, at least in America, are made today, they have virtually no effect on exhaust flow. Any backpressure that may create is part of the design of the whole exhaust system. Cutting them off would be a bad idea, not to mention illegal. Hope this helps.

Answer 4

Pan of crystals? If that's what you had on your Transam, it explains a lot about American cars!

Catalytic converters do reduce noxious emissions, of that there is no doubt. Quite possibly you found a slight increase in performance without it, however properly set-up cars run better with the cat in place, they're designed for it.

And in many places it's illegal to remove it.

Answer 5

You might get a 15% increase in fuel efficiency but what is the percentage incease in noxious emissions? Although you are using less fuel, you are not removing the emissions any longer and that is the whole point of cat converters.

Answer 6

you may have gotten better milege, but only because you removed a "flow blocker," aka, those crystals.

milege and emmissions are very losely related. by removing that flow blocker, you gain power, and milege, but you are no longer filtering the exhaust as much as with the converter.

bigger exhaust pipes, and dual pipes show the same performance increases over a single exhaust with smaller pipes.

so you basically get what i'm saying about increased flow from removing the converter.. right?

Answer 7

They reduce Nitrous Oxide emissions - And it's illegal to remove catalytic converters in the US

Answer 8

No token gesture and not bemused. They work. Of course they ruin exhaust gas suicide attempts. You'd die of boredom first.