Easy Way to Gut a Cat Converterby Lennon Simpson
Catalytic converters clean exhaust gases of harmful chemicals and gases that pollute the atmosphere. However, they also restrict the free flow of exhaust and suck power from a car. Most high performance enthusiasts install a high flow converter that eliminates this restriction as much as possible while still cleaning exhaust gases. For the hardcore racer, however, even the highest flowing converter is too much, so they need to remove it all together. It should be noted that running a car on the streets without a catalytic converter is illegal. This modification is for off-road racing use only.
Gutting Your Converter
The simplest and cheapest way to remove the catalyst is simply to gut your converter. Get the car on a lift or stands or however you choose to get under it and unbolt the converter. Be sure to do this after the car has been off for several hours, as exhaust piping can remain hot for quite some time. Also, the heat will cause the metal to expand, making it more difficult to remove. Once you've removed the converter, the catalyst will look like a honeycomb on the inside. It's solid and tough to remove, but using a crowbar as a chisel and a hammer, you can break it out. It can be a slow going process to remove all of it, but the process can be aided by using a drill with a long bit to start weakening the honeycomb structure, which is very sturdy. Once all of the catalyst is removed, replace the empty converter shell and your car is good to go. There are, however, problems with doing this. Removing the catalyst not only makes your car illegal for street use, but the empty shell of the converter is a good deal wider than the rest of the exhaust system. This causes problems with pressure changes and velocity inconsistency which can actually negatively impact the performance of your car rather than enhance it.
If you are willing to spend the money, a less labor-intensive way to remove the catalyst from your car is simply to buy a test pipe from one of the multitude of after-market exhaust companies. A test pipe is a length of empty exhaust piping equal to the length of a catalytic converter. Simply unbolt your converter and bolt in your test pipe. No dealing having to deal with chiseling away at catalyst or dealing with the mess. The best part about a test pipe is that you can keep your converter fully intact. This allows you to run with the test pipe on the track during the weekends, but replace your converter and be street legal, should you desire to drive your car too and from work as well. Because the test pipe will also match the diameter of your exhaust, there is no worry about fluctuating pressure or velocity in your exhaust gases.
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