Benefits of Removing Cat and Running Straight Pipe?

[alhope34]

A lot of people around here with loud mufflers on their civics get their exhaust shops to cut a hole at the top of the cat and hollow it out then wield the top back on so from underneath unless you look really close, it looks normal. But really inside it's just a straight pipe through the cat's outer shell.

In Ontario we have really strict emissions testing, but it isn't too hard to get emissions faked. When I got my first car I didn't know it was so badly beat up as it was, and I was told by a few mechanics the best and easiest solution to solve the emissions problem was to get a new car, which I couldn't do. When I ran out of temp plates the DMV would give me, I finally had to get the papers done. Still had the car 4 months after that till it totally died. I even replaced the cat on that car and ALL of the o2 and no2 sensors on the exhaust...still didn't fix the emissions. Kept failing on what the place called "nox". Limit was 200 and something and my car was doing in the 2500's

[BailOut]

Originally Posted by alhope34

Kept failing on what the place called "nox". Limit was 200 and something and my car was doing in the 2500's

"Nox" is short for "noxious emissions". Gasoline-burning vehicles produce 3 kinds of emissions:

1) GHG (greenhouse gases - Carbon Dioxide and Nitrous Oxide)

2) Nox (noxious emissions - Nitrogen Oxide, Carbon Monoxide, Sulfur Dioxide, various carcinogenic (cancer-causing) hydrocarbons... all the stuff that acid rain is made of)

3) Passive (paint flakes and fumes, leaking fluids, etc.)


A catalytic converter helps mostly with the "nox" group.

[alhope34]

Originally Posted by BailOut

"Nox" is short for "noxious emissions". Gasoline-burning vehicles produce 3 kinds of emissions:

1) GHG (greenhouse gases - Carbon Dioxide and Nitrous Oxide)

2) Nox (noxious emissions - Nitrogen Oxide, Carbon Monoxide, Sulfur Dioxide, various carcinogenic (cancer-causing) hydrocarbons... all the stuff that acid rain is made of)

3) Passive (paint flakes and fumes, leaking fluids, etc.)


A catalytic converter helps mostly with the "nox" group.

My car failed harder with the new cat. And I even drove it 500km before I got it re-tested. got 1000 or so with the old cat that was all clogged. And yes, the new cat was also a three-way. I know two way cats don't work as wekk

[WolfWings]

Originally Posted by BailOut

"Nox" is short for "noxious emissions". Gasoline-burning vehicles produce 3 kinds of emissions:

No, incorrect, wrong, wrong, wrong. As wrong as claiming Annie Lennox wrote a song about walking on propane gas.

nox stands for a single chemical family being tested for: Nitrous OXides.

Petrol-based engine emissions-testing systems aren't even remotely categorized like you listed. The 'bad chemicals' they produce are:

• Nitrous OXides (two Nitrogen atoms and a random number of Oxygen atoms)
• Carbon Monoxide (two Carbon, one Oxygon)
• Unburnt HydroCarbons (one Hydrogen, one Carbon) actually.

These (NOX, CO, HC) are what are tested for in a tailpipe test, also. A three-way cat converts NOX better if you're running a rich mixture, or converts the other two better if you're running a lean mixture. Basic chemistry, replace a cat, adjust the fuel mixture and you can pass an emissions test almost always. California is so hard to pass because of their inspections, which include the most common ways to adjust the fuel-mixture having to be factory-spec.

At least research your claim a little before spouting it off like it's gospel, 'kay?

[BailOut]

Originally Posted by WolfWings

At least research your claim a little before spouting it off like it's gospel, 'kay?

Either I was misinformed at the testing station I asked lot of questions at, or Wikipedia is wrong. Either scenario is highly possible.

The end result is the same regardless, though:

Catalytic converter == good, hence why it is mandatory in most parts of the developed world.

No catalytic converter == acid rain, contaminated water, etc.

[WolfWings]

Originally Posted by BailOut

Either I was misinformed at the testing station I asked lot of questions at, or Wikipedia is wrong. Either scenario is highly possible.

The end result is the same regardless, though:

Catalytic converter == good, hence why it is mandatory in most parts of the developed world.

No catalytic converter == acid rain, contaminated water, etc.

Nah, I'll disagree with you.

Low emissions == good, yes. But catalytic converters are just the easy way to 'force' all emissions down quickly, ergo why they were made basically manditory.

The Honda Civic was created initially to avoid having to add a catalytic converter (CVVC was the original engine-tech nickname, ergo the series-name CiViC) for example, and I've run vehicles with the Cat removed that still passed the tailpipe-sniff test just fine as long as they were well-tuned and well-maintained.