Catalytic Converters

 Here is something kinda interesting. I just spent the better part of yesterday installing headers on my truck. Since I replaced the factory Vortec heads with a set of Vortec aluminum heads with 2.02 intake valves which actually worked out to be cheaper to purchase. As long as you use hardened pushrods with the guide plates there is generally no problems. The factory Vortec head has a smaller intake valve and therefor creates a higher low end velocity in the intake runner during the intake pulse. They also flow extremely well under half inch lift. So given the fact the the aluminum heads had 2.02 valve I lost a little of my low end and gained power through my mid range and higher end. Now,with the installation of headers I should have gained my low end power back and then some due to the nature of the way headers work. When I got the headers bolted up I of course could not resist the temptation to fire it up. Damn,I was like a kid in a candy store! I could feel the crisp throttle response and the small block revved up very quickly. I then bolted up the rest of the system and discovered that my new found power was not there. Since I have dual pipes and a set blue bottles I started to think about what the hell could be restricting my exhaust. The only conclusion I could come to was the catalytic converters. So I decided to do a little reading on them.

 Here's what I found. The catalytic converter is either a two way or a three way converter. The two way converter has two functions:

1. Oxidation of carbon monoxide to carbon dioxide: 2CO + O₂ → 2CO₂
2. Oxidation of unburnt hydrocarbons (unburnt and partially-burnt fuel) to carbon dioxide and water: C_xH_2x+2 + [(3x+1)/2] O₂ → xCO₂ + (x+1) H₂O (a combustion reaction)

The three way converter serves three functions:

1. Reduction of nitrogen oxides to nitrogen and oxygen: 2NO_x → xO₂ + N₂
2.  Oxidation of carbon monoxide to carbon dioxide: 2CO + O₂ → 2CO₂
3. Oxidation of unburnt hydrocarbons (HC) to carbon dioxide and water: C_xH_2x+2 + [(3x+1)/2]O₂ → xCO₂ + (x+1)H₂O

The research and info I found goes into a whole bunch of scientific chemical explanations that don't mean much to me so I'll save you the hassle of them. However,did you notice that both  types of converters convert carbon monoxide to carbon dioxide or CO2. CO2 is considered a trace gas on our planet however human activities have increased the production of CO2 by 35% since the beginning of the industrial age and is considered a Green House Gas. So why are we employing the use of and invention of our vehicles that actually increases the CO2 levels in our atmosphere? Basically we have catalytic converters on every vehicle that comes off the line. And of course we have everyone and their dog in the scientific community telling us we have to reduce our carbon footprint. Everyone that drives is contributing to a problem that was a solution to a problem that was just a band aid in the first place. There has to be a better way.

Now,on the radio there have been commercials stating that cars built prior to 1995 pump out 19 times the pollution the new cars produce. This of course is very inaccurate. The actual number is 19% on average. The government of Canada just wants you to think that you need a new vehicle and of course the tax money involved doesn't hurt either. There have been improvements in engine technology that have helped reduce the amount of Green House Gasses that vehicles produce,namely the combustion process. The shape and design of the combustion chamber inside your engine plays a huge roll in how gasoline burns. The Vortec cylinder head is a design that causes the air fuel mixture to burn faster and hotter. Serving two purposes, burning faster produces more power,burning hotter reduces the amount of toxic green house gasses produced.

Edelbrock 60739 Performer RPM Cylinder Head is a prime example of a design that actually helps reduce the emissions produced by the internal combustion process.

Edelbrock 60739 Performer RPM Cylinder Head

 Now,notice how small the the chamber is? This is the area where the valves are. If you notice how the shape of the chamber favors the intake valve at the the spark plug hole is closer to where the gases come into the chamber? This design helps to increase the speed and temperature of combustion. Giving both the benefits of more power and reduced emissions. It also helps your vehicle's engine function smoother with less required fuel to produce the power required to move the vehicle and that also helps with fuel economy. That only works if you don't have your foot in it all the time because of the new power so bare that in mind! I have aluminum heads on my truck and I get around 28 MPG on the highway. I also maintain my truck very diligently.

There are other ways to help reduce these emissions and we have to educate ourselves in order to stay current on issues such as these. If we don't then for the most part we rely on what we are told. Some of the information we get is very biased and geared towards helping us believe that we have to take what we are told as gospel. A few minutes and a little effort will help us realize that for the most part we should be taking the time to find out for ourselves so that we don't get taken advantage of. Or we could just rely on what we are told and be like sheep. But,I know people are smarter than that.

We should take into consideration that factory installed catalytic converters are designed to just get the job done. For the performance enthusiast, replacement converters like the MagnaFlow will help with the restriction you would normally find with stock applications. Bare in mind that the removal of the catalytic converter is illegal and most if not all areas of North America and cause the vehicle to fail an emissions test. For vehicles with the OBD II computer systems there are sensors located behind the catalytic converters that will register a trouble code if removed not to mention the on-board diagnostic system will attempt various commands to fix the problem because it senses a trouble code. This can be a recipe for disaster. However,if you want to just do away with the converter itself then the use of oxygen sensor simulators are required so that the "closed loop" control system does not retard the performance of your application.

Now,I would like to touch base again on the environmental impact of catalytic converters.
Although catalytic converters are effective at removing hydrocarbons and other toxic emissions,most of the gasses leaving the tailpipe that has gone through a converter is CO2 which is a green house gas and nitrous Oxide, N2O that is 300 times more noxious than carbon dioxide. All in all,the use of catalytic converters creates more problems than it fixes. But,this is an example of a situation where we did not educate ourselves enough and had these things rammed down our throats before we knew enough about them.