Catalytic converters have proven to be reliable and effective in reducing noxious tai

[skiboarder]

However, they may have some adverse environmental impacts in use:

The requirement for a rich-burn engine to run at the stoichiometric point means it uses more fuel than a lean-burn engine running at a mixture of 20:1 or less. This increases the amount of fossil fuel consumed and the carbon-dioxide emissions of the vehicle. However, NOx control on lean-burn engines is problematic.[citation needed]
Although catalytic converters are effective at removing hydrocarbons and other harmful emissions, they do not solve the fundamental problem created by burning a fossil fuel. In addition to water, the main combustion product in exhaust gas leaving the engine — through a catalytic converter or not — is carbon dioxide (CO2).[14] Carbon dioxide produced from fossil fuels is one of the greenhouse gases indicated by the Intergovernmental Panel on Climate Change (IPCC) to be a "most likely" cause of global warming.[15] Additionally, the U.S. EPA has stated catalytic converters are a significant and growing cause of global warming, because of their release of nitrous oxide (N2O), a greenhouse gas over three hundred times more potent than carbon dioxide.[16]
Catalytic converter production requires palladium or platinum; part of the world supply of these precious metals is produced near Norilsk, Russia, where the industry (among others) has caused Norilsk to be added to Time magazine's list of most-polluted places.[17]

 

[cammeddrz]

contrary to the title of this thread i have always been under the impression that cats merely help in reducing the hydrocarbons (in the form of unburned fuel) by being a "furnace" that burns un-burned fuel......nothing more

as i recall from emissions inspector class: un burned fuel hydrocarbons are said to be the most harmful. that is why when you get your emissions done they always check your fuel cap to verify that it is not allowing unburned fuel to get into the atmosphere via vapor.

and yes cats do little if anything to help with any other emissions

 

[BRUTUS_T_HOG]

lets come up with something better then.

 

[cammeddrz]

lets come up with something better then.

cats work quite well in burning un-burned fuel

 

[BRUTUS_T_HOG]

im fine with cats... OP seems to dislike them.

if there is a better alternative lets do it.

 

[skiboarder]

cats work quite well in burning un-burned fuel

when i was reading this about cats my thoughts were "we are just robbing peter to pay paul". We took lead out of gas so we can't run higher compression thus a more efficient engines. Lead clogs cats. So now we use more fuel to run lower power engines. The whole thing seem counter productive to me.
I don't know what the answer is, but I am sure there is a better solution somewere.

HYDROGEN!!!!!!

 

[Surrey]

Have you actually had to do emissions testing on a vehicle?
I had a 1985 Jeep Cherokee, with 2.5l 4cylinder. It failed aircare big time. Too much Carbon Monoxide, too much Nitrogen oxide (both exhuast gases, not unburned fuel) and too much hydrocarbons.

With replacing the catalytic converter, I was able to pass on all 3 parameters.

They are not just a furnace, they create a chemical reaction to add, subtract, or separate oxygen atoms to create less harmful substances, like O2, N2, CO2 and water instead of CO (carbon monoxide) or NO (nitrogen oxide)

 

[Jason]

wow. There is so much fail here I can't even start to correct it.

Lead didn't aid compression. It aided valve seats.

Do you believe that engines use more gas now than they did in the 70's?

That's a start. Enjoy.

 

[JohnnyO]

wow. There is so much fail here I can't even start to correct it.

CO2 is plant food, not a greenhouse gas that causes global warming.
Cats greatly reduced hydrocarbons which was the main harmful pollutant emitted by cars. As someone who is old and remembers this stuff, cars built from '72 to '74 were tuned to pass emissions tests (instead of running well) and basically ran like crap and used a lot more gas than '71-earlier models. Adding cats in '75 allowed the manufacturers to tune the cars to run better and get better mpg.

In 1973 my dad got a new Pontiac Catalina. From '74 to '78 we had some record cold winters and you had to take the air cleaner off EVERY morning and hit it with Quick Start to get the thing to turn over. Our other car was a '64 Impala, one step from the junkyard and no emissions equipment at all, and it would kick over in -20* temps no problem. Gas mileage on the new Pontiac was horrible, downhill with a tailwind it would get 10 mpg.

Lead in the fuel did lubricate the valves but it also allowed higher compression as well as release lead into the atmosphere. The Federal govt dictated that all cars had to run on low-lead or no-lead gas by 1972. As a result, GM lowered compression in '71 and Ford and GM followed in '72.

 

[skiboarder]

wow. There is so much fail here I can't even start to correct it.

Lead didn't aid compression. It aided valve seats.

Do you believe that engines use more gas now than they did in the 70's?

That's a start. Enjoy.

Your right. Lead does not help with compression. It does retard ignition of gases which keeps knocking and pinging down.
Engines are more efficient now, but the could be even more so.
I used to live next to a chemist for a gas company. He told me the approximately 80 percent of you fuel at the pump is additives. These additives put out emissions that they don't even test for.
We just need a new system.

 

[cammeddrz]

Have you actually had to do emissions testing on a vehicle?......blah, blah, carbon monoxide, blah, blah......... nitrogen oxide blah, blah

so anyway i left out the other gases and to what extent a cat reduces them because skiboarders post already addressed that (however i make no comment on the validity of his post). i brought up what hadn't been mentioned which is the cat's main job, which is also the job it serves most effectively

i decided to leave it at:

cats do little if anything to help with any other emissions

if i wanted to split hairs over how well it reduces NoX, and Co (which varies greatly between vehicles, and whether or not they have air pumps as well) a person could say: "nuh-uhhh i put a new cat on and passed with flying colors" , and the next guy would say: "yeah-huhh, i put a new cat on and still failed"
and in the end someone ends up going "neener-neener-neener"

 

[cammeddrz]

this thread mentions a bunch about lowered compression, and ethanol and wanting "something better"

alcohol allows for tons of compression. and alcohol not being petroleum based could be evaporating out of a puddle and still wouldn't release hydrocarbons into the atmosphere.
alcohol also releases near nothing as far as Nox. and pretty much nothing as far as carbon monoxide.

i used to run my tank really low and dump in a gallon of my race methanol before an emissions test on my personal vehicle, that 1984 camaro with no cats and a huuuuge cam passed like a 2005 civic, ran like crap, but passed really well

i say that it is time to sh-t or get off the pot with alcohol in our fuel, lets go all the way, or keep it out entirely. the only downside is that alcohol inherently contains more oxidizers within itself so a lot more fuel (near double that of gasoline) is needed to create a proper air/fuel ratio. so actual miles-per-gallon would go down but so would emissions. and the production of alcohols like ethanol are by-products of food production so we wouldn't be needlessly depleating resources to create fuel. the logistics of producing the needed volume of alcohol would likely prove to be the daunting task

 

[JPRanger03]

CO2 is used by plants in order to generate various carbohydrates, but it's also a greenhouse gas. But, other gases (carbon monoxide, nitrous oxide, etc.) absorb much more infared radiation than CO2, and so they have the potential to contribute more to the greenhouse effect, although they seem to be present in lower concentrations.

Like someone stated on here before though, we need something new or an improvement of the the systems we already have. Maybe smaller displacement, direct injected turbocharged powerplants (Ecoboost)?

 

[JohnnyO]

Like someone stated on here before though, we need something new or an improvement of the the systems we already have. Maybe smaller displacement, direct injected turbocharged powerplants (Ecoboost)?

Europe is all over small turbodiesels, great mpg but they won't pass emissions over here. Pick your poison (so to speak).

 

[JPRanger03]

Europe is all over small turbodiesels, great mpg but they won't pass emissions over here. Pick your poison (so to speak).

This is true, although I remember reading somewhere that the new Ecoboost powerplants offer a 15% reduction in greenhouse gas emissions (I believe it was in reference to the 4 cylinder version)