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I have read a post a few months ago about removing cats from your exhaust and having starting problems in cold weather. The reason was having to do with the cat helping heat up the exhaust system or something.

The reason I would like to know is because I would like to run catless but I go snowboarding near 15 times a year and I don't want to be the LOSER that can't start his car when it is time to leave. Please let me know.

Also this is probably a dumb question, but if I run like 3" turboback exhaust system, which will give my car less back pressure, will this effect hill climbing capabilities. Like climbing steep grades on the way to the mountains. Or is this just the opposite. I will give you more hill climbing power? People in Colorado should know about this.

thanks in advance,

Kurlee Daddee
(THE ORIGINAL)
 

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I think you may just be confusing some of the statements you have heard. The purpose of the uppipe cat is specifically to combat cold-start emissions. A cat will not function until it reaches a certain operating temperature, and the uppipe's proximity to the manifold means that this cat heats quickly. Therefore, in a situation where the uppipe cat has been removed, and considering that it will take a long time for the rear cats to reach operating temperature in extremely cold conditions; a cat-efficiency CEL will usually result as the rear O2 sensor detects an abnormally high percentage of unburnt fuel.

I never had any starting problems last winter except after my car had been sitting unused for 3 weeks. I run one cat in the center pipe.

-Pace
 
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