Catalytic converter, delete or replace? Benefits of each?

[Xektrez]

Ok so sorry for the unrelated post, because this is a question for my 1999 Honda Accord. I hope this isn't breaking the rules, since it's a 240sx forums. But I plan on getting a 240 soon, and this question could go for any car. I figured this forum would know a little more about this than the Honda forums. So I would like to get opinions.

Yes, I know it is against emissions to remove it, but I'm pretty sure I do not have emissions. It says on the BMV for Indiana (where I live) that you must get it inspected every 2 years for Lake and Porter counties. But those counties are not where I live, I actually don't like anywhere near them because I looked them up and that's not my county. So does this mean I do not have an emission standard. Here is the link for the site: http://www.in.gov/bmv/2655.htm.

But anyways, back to my original question. Is it better to remove it or replace it? It's one of the codes for my check engine light, and I would like to get it off by the time I sell the car. And I think it'll be a good experience to work on it. I haven't had much experience with working on cars, but I get the gist. I just want to get some experience. And I've heard that you can either get a new catalytic converter, or get a pipe to fill the void. I know the car will be louder without the catalytic converter, but is that the only change? Will either option increase mpg or any other benefits? I've heard it can boost hp to get rid of it, but I'm sure that's either not true or it raises it by like 1hp lol. But is it harder on the engine to have to spit the fumes through the converter, because I feel like it's an obstruction in a way, but idk honestly. Never worried about this problem until I thought about it.

I'm going to take a look at it in the morning, to check and see what goes where and where the plug goes into it. Also, if I deleted it what would I do with the sensor? A sensor plugs into it right? Would like to know you guys' opinions on this!

Edit: Also is it really bad on the environment to delete the cat? I know the main reason for the cat is to reduce the toxins, but is it really a substantial increase in toxins into the air?

[asoomal]

Yes it is pretty bad for the environment to run without a catalytic converter, and it does make quite a difference.

I'd just stick in a cheap replacement cat, you won't gain much without a cat.

[centralcoaster33]

According to the omniscient wikipedia, there were 255.8 Million passenger cars registered in just the United Sates in 2013. That is a lot of exhaust and every catalytic converter helps. Imagine if every smoker everywhere only littered their butts instead of using ashtrays and garbage cans and then no one bothered to ever pick them up. It adds up. You could read up on emissions systems. They are interesting.

I'm pretty sure your 1999 car has a pre-cat and a post cat sensor and the one after your cat isn't getting the right signal, so it tells the computer to adjust the air-fuel ratio in an attempt to control emissions and temps. Deleting the cat internals reduced exhaust backpressure, but also reduced the ECU's efficiency programming. You could potentially lose horse power by merely deleting a cat. You can get the power back, but have to deal with the computer side of things.

It can be tough to sell a used car with a check engine light on.